Molecular Biology

Tumor development represents the loss of multiple signaling mechanisms regulating the control of cell growth. After malignant transformation, the processes of replication (mitosis), programmed cell death (apoptosis), and the interaction of a cell with its surrounding environment are altered. Advances in molecular biology have allowed for the identification of many of the mutations associated with this transformation. Contemporary molecular analysis of tumors is providing insight into the processes of malignant transformation and tumor progression.

H-ras, a member of the ras gene family, encodes a plasma protein (p21), which has a role in the transduction of mitogenic signals to the intracellular environment. A synergism between H-ras and HPV is believed to play a role in the induction of squamous cell carcinoma. In human studies, 22% of oral squamous cell carcinomas expressed H-ras, whereas 11% expressed H-ras and HPV. All specimens of oral verrucous carcinoma that expressed H-ras (25%) demonstrated evidence of HPV DNA.¹⁷

HPV is a mucosotropic virus that has been closely associated with cervical carcinoma in women, such that HPV 16 and 18 are considered carcinogenic. In oral cavity specimens, variable detection has been reported with rates ranging from 19% to 78%.^18,19 Findings of HPV 16 within normal tissue at the margins of tumor specimens have suggested that infection is not a sole event preceding malignant transformation. Rather, it has been postulated that HPV may play a role in the early events of carcinogenesis. HPV oncoproteins E6 and E7 have the ability to bind and degrade tumor suppressor gene products of p53 and pRB, respectively. This binding can impair the capacity of the cell cycle to arrest for the repair of DNA damage and results in an accumulation of genetic changes assisting transformation.¹³

Smith and colleagues detected a significant increase in the presence of HPV DNA within oral cavity carcinoma samples (15%) compared with controls (5%). In addition, they noted that HPV (odds ratio [OR]-3.7) was a risk factor for carcinoma, independent of tobacco (OR-2.63) and alcohol use (OR-2.57).²⁰ Maden and coworkers noted an increased risk for oral cavity carcinoma with the presence of HPV 6 and HPV 16. Similar to Smith and colleagues, they also demonstrated HPV infection to be a risk factor, independent of age and tobacco and alcohol use.²¹

Costa and colleagues examined resectable oral cavity carcinomas for biomarkers predictive of chemosensitivity before primary surgical treatment. They found that tumors negative for glutathione S-transferase (GST-π) were more responsive to cisplatin and 5-fluorouracil than tumors that were GST-π-positive. They also noted that lack of bcl-2 expression was consistent with an improved 3-year disease-free survival. No relationship between p53 activity and chemotherapeutic response was observed.²²

Overexpression of mutant p53 has been associated with carcinogenesis at multiple sites. Point mutations in p53 have been reported in up to 45% of head and neck carcinomas. Brennan and colleagues have evaluated the concept of primary site margin assessment of specimens on the basis of p53 staining to guide the need for further treatment.^23,24 Koch and others have noted that p53 mutation is a key event in the malignant transformation of greater than 50% of head and neck squamous cell carcinomas in smokers.⁸

Her2-Neu overexpression has been demonstrated in a subset of squamous cell carcinomas.²⁵ Expression of Her2-Neu and heat shock protein (HSP)-27 have been associated with regional treatment recurrence in patients with oral cavity and oropharyngeal carcinomas treated with primary radiotherapy.²⁶

Koch’s tumor progression model has demonstrated that 3p is a site of early loss of heterozygosity, 4q is a late event, and 11q13 is the site of the cyclin D1 gene. Reviews of the head and neck literature have suggested the role for p53, EGFR, TGF-α, and cyclin D1 in predicting clinical outcome for patients with squamous cell carcinoma.²⁷

The Akt receptor has been correlated with the histologic progression of oral premalignant lesions to oral carcinoma. Massarelli and colleagues²⁸ demonstrated that phosphylated-Akt, when highly expressed, is associated with recurrence and shorter disease-free survival independent of a patient’s overall staging.

Arteriovenous Anatomy

The arterial supply to the oral cavity includes multiple contributions from the external carotid artery. The lingual artery provides the majority of the vascular supply to the oral tongue and tongue base. Identification of the artery within the neck requires the exposure of the floor of the submandibular region. The artery is found deep to the hyoglossus muscle and requires the division of the muscle for maximal exposure. Superficial to the hyoglossus and deep to the mylohyoid muscle is the hypoglossal nerve and lingual veins (Fig. 96-4). An understanding of this relationship can aid in the localization of the artery when necessary for microvascular reconstruction or selective ligation. The vein, which closely approximates the nerve in this region, is prone to injury during dissection and necessitates care when attempting to obtain hemostasis if hypoglossal nerve injury is to be avoided.

Figure 96-4. A, Musculature of the submandibular region and relationship of the lingual and hypoglossal nerves to the submandibular gland. B, Deeper anatomy of the submandibular fossa. The hypoglossal nerve runs deep to the mylohyoid muscle and superficial to the hyoglossus muscle. The lingual artery runs deep to the hyoglossus muscle and ascends to divide into deep and dorsal lingual arteries and the sublingual artery.

The hard palate blood supply is derived from the greater palatine and the superior alveolar arteries. After branching off the descending palatine artery at the greater palatine foramen, in the region medial to the second maxillary molar, the artery runs anteromedially within the soft tissue of the hard palate (Fig. 96-5). The venous drainage is to the pterygoid plexus and subsequently to the internal jugular venous system. The superior alveolar arteries (anterior, middle, posterior) arise as terminal branches after the transition of the internal maxillary artery to sphenopalatine artery at the pterygopalatine fossa. These arteries provide blood supply to the maxillary gingiva, alveolar ridge, and dentition.

Figure 96-5. Primary and secondary portions of the hard palate. The relationship of the hard palate to the course of palatine nerves is important to consider when perineural invasion is suspected with squamous cell carcinomas or minor salivary gland malignancies in this region.

The facial artery crosses over the lateral aspect of the mandible approximately 1 cm anterior to the ascending ramus and courses toward the oral commissure where it gives rise to the labial arteries. These paired vessels are readily apparent during lip-splitting procedures and anastomose in the midline to create a vascular ring.

The primary vascular supply to the mandible and the lower dentition is from the inferior alveolar artery. Blood supply from the mandibular periosteum becomes more important with advancing age. The inferior alveolar artery, vein, and nerve enter the mandibular foramen along the medial aspect of the ramus of the mandible. Before their entry into the foramen, both the nerve and artery send off branches that extend anteriorly to supply the mylohyoid muscle.

The posterior floor of the mouth and retromolar trigone have an arterial supply and venous drainage similar to that of the anterior tonsillar region. The ascending pharyngeal and lesser palatine vessels contribute to the vascularity that may be encountered with surgical procedures at this site.

Subsites of the Oral Cavity

Lips

The lips represent a transition from external skin to internal mucous membrane that occurs at the vermilion border. The underlying musculature of the orbicularis oris, innervated by the facial nerve, creates a circumferential ring that allows the mouth to have a sphincter-like function. The sensation for the upper lip is supplied by the infraorbital nerve (CN V₂), whereas the lower lip is provided by the mental nerve (CN V₃). Lymphatics from both the upper and lower lips drain primarily to the submandibular lymph nodes, yet midline lower lip lesions may present with submental lymphatic spread. In addition, the upper lip may drain to preauricular, infraparotid, and perifacial lymph nodes (Fig. 96-6).

Figure 96-6. Lymphatic drainage pattern for the upper and lower lips.

Alveolar Ridge

The lateral aspect of each alveolar ridge is represented by the mucosal sulcus created by the transition of tissue to buccal mucosa. On the lower alveolus, the medial margin is marked by the transition to the floor of the mouth and, on the upper alveolus, the transition is the horizontal orientation to the hard palate. The posterior margin of the lower alveolus is the ascending portion of the ramus of the mandible; whereas it is the superior aspect of the pterygopalatine arch for the upper alveolus. The close approximation of mucosa to underlying bone assists early bone invasion for malignant tumors in this region.

Oral Tongue

The oral cavity portion of the tongue is defined as that portion anterior to the linea terminalis. The tongue is composed of four intrinsic and four extrinsic muscles separated at the midline by the median fibrous lingual septum. The extrinsic muscles originate outside the substance of the tongue and include the genioglossus, hyoglossus, styloglossus, and palatoglossus. Of these, the genioglossus, which functions to depress and protrude, provides the majority of the bulk to the tongue. The paired intrinsic muscles of the tongue (superior-inferior longitudinal, transverse, and vertical) lie superficial to the genioglossus and function to alter the overall shape of the tongue. These muscles run with the tongue in three different orientations. This lack of distinct planes between muscles can allow for a diffusely infiltrating pattern of tumor growth. All of the musculature of the tongue derives its innervation via the hypoglossal nerve with the exception of the palatoglossus, which is supplied by a pharyngeal branch of the vagus nerve. The general sensory innervation of the anterior two thirds of the tongue is provided by the lingual nerve. It arises deep to the lateral pterygoid muscle, spirals from lateral to medial around the submandibular duct, and divides into several branches that lie in the submucosa of the oral tongue. The special sensory innervation of the oral tongue for taste is provided by the chorda tympani nerve (CN VII) that travels to the anterior tongue along with the lingual nerve. In contrast, both functions are performed by the glossopharyngeal nerve for the base of tongue.

The lymphatic drainage of the oral tongue varies by the region within the tongue. The tip drains preferentially to submental nodes, whereas the lateral tongue drains primarily to the levels I and II (Fig. 96-7). However, it is important to note that a defined lymphatic pathway from the lateral tongue does exist and drains directly to the level III/IV nodal group. The base of the tongue drains to the upper cervical lymphatics. The lack of anastomoses between the anterior tongue lymphatics results in lateralized oral tongue lesions tending to drain ipsilaterally. This is not the case with base-of-tongue lesions where crossover and bilateral cervical lymphatic spread may readily occur.

Figure 96-7. Lymphatic drainage pattern of the oral tongue, base of tongue, and floor of mouth.

Retromolar Trigone

This region is represented by the mucosa overlying the ascending ramus of the mandible toward the coronoid process. It is continuous with the buccal mucosa laterally and the anterior tonsillar pillar medially. The superior extent is the maxillary tuberosity and the anterior margin is the posterior aspect of the second mandibular molar. The same considerations that were true for alveolar lesions exist for this anatomic site, given the close approximation of mucosa to the underlying mandible. Lower lip paresthesia may be an indication of perineural invasion at the level of the mandibular foramen with these lesions. The sensation to this region is provided by the lesser palatine nerve and branches of the glossopharyngeal nerve. It is the presence of CN IX that causes patients with lesions within this area to present with referred otalgia. The primary lymphatic drainage for this region is to the upper cervical-jugulodigastric nodal group (Fig. 96-8).

Figure 96-8. Lymphatic regions of the upper neck.

Premalignant Lesions

A discussion of the premalignant lesions of the oral cavity requires a review of the definitions commonly used in describing the gross and histologic appearance of these growths.

Leukoplakia is white, mucosal-based keratotic plaque that cannot be wiped free from the underlying tissue. This is a clinical term without a definitive histologic definition. Leukoplakic lesions may demonstrate parakeratosis, hyperkeratosis, and acanthosis on histologic examination. Paradoxically, an increased risk of malignant transformation of leukoplakic lesions is seen more commonly in nonsmokers compared with smokers. If a leukoplakic lesion is associated with an area of dysplasia (in 1% to 3% of all lesions), the risk of progression to malignancy increases seven-fold. Banoczy followed 670 patients with leukoplakic lesions for 3 years and noted that 31% of lesions disappeared, 30% improved, 25% experienced no change, and 7.5% demonstrated local spread. Only 6% of lesions demonstrated eventual progression to squamous cell carcinoma.³⁷ Syphilitic leukoplakias seen in tertiary syphilis have a higher reported rate of malignant transformation.³⁸

Erythroplakia is a red mucosal plaque that does not arise from any obvious mechanical or inflammatory cause and persists after removal of possible etiologic factors. The associated risk for progression to carcinoma is significantly greater than that for leukoplakic lesions. Shafer and Waldron³⁹ resected erythroplakic lesions in 58 patients and found that 91% had evidence of invasive, carcinoma in situ, or severe dysplasia within specimens.

Submucosal fibrosis, most frequently encountered in individuals who chew betel nut, is associated with poor oral hygiene, advanced periodontitis, and oral carcinoma. The buccal mucosa becomes thickened and the entire cheek becomes fibrotic, resulting in trismus. Resection of tumors arising in the buccal mucosa in patients with submucosal fibrosis can be challenging and reconstruction can be complicated by wound breakdown and poor healing.

Lichen planus, in particular the erosive subtype, has also been associated with the development of oral carcinoma. The etiology of lichen planus is unknown. T-cell lymphocyte infiltration is noted in this lesion, yet the development of lichen planus is not typically associated with immunologic disorders. The typical patient is a female in the fourth decade of life. Lesions demonstrate a lacy pattern of white striae. Atrophic lesions are red and smooth, whereas erosive lesions have depressed margins and are covered by a layer of fibrinous exudate. An estimated 1% risk of malignant change over 10 years has been reported.³⁸

Dysplasia is the abnormal maturation and differentiation of mucosal epithelium with features of an increased nuclear-to-cytoplasmic ratio, loss of polarity, increased mitoses, and loss of intercellular adherence. Dysplasia is graded as mild, moderate, and severe.

Verrucous hyperplasia is a histologic finding that appears similar to verrucous carcinoma yet differs from the malignant form in that it does not invade the lamina propria.

Necrotizing sialometaplasia, although appearing clinically ominous, is benign. The typical feature is a butterfly-shaped area of ulceration at the junction of the hard and soft palate in the region of the palatine foramen. The etiology of this clinical lesion is necrosis of minor salivary acini usually secondary to localized pressure injury. This may be seen in the scenario of a poorly fitting or overused denture.

Squamous Cell Carcinoma and Variants

Several variants of squamous cell carcinoma exist and may be encountered in the oral cavity.

Sarcomatoid squamous cell carcinoma demonstrates a heterogeneous appearance with spindle-shaped cells interwoven with squamous cells. The cytologic behavior of this variant is considered aggressive with a reported metastatic rate of 37%.⁴⁰ Basaloid carcinoma is also considered a high-grade variant with reported 64% incidence of regional metastases and 44% incidence of distant metastases, and it is associated with 38% mortality at 17 months.⁴¹ However, one report notes that when clinical T and N staging are matched, the 5-year disease-free survival associated with oral basaloid carcinoma is similar to that of poorly differentiated and moderately differentiated oral carcinomas.⁴²

A thick zone of nonproliferating and nonkeratinizing cells distinguishes verrucous carcinoma histologically. The typical presentation is on the buccal mucosa (50%). It is considered a low-grade variant of squamous cell carcinoma and is exophytic in appearance. It has the capacity to invade locally yet carries a low risk of regional spread. Traditionally, this lesion has been considered to be “radioresistant” and surgical excision has been the treatment of choice.

Other Pathologies

Additional pathologies to consider in the differential diagnosis of oral cavity lesions include pyogenic granuloma, pseudoepitheliomatous hyperplasia, lymphoma, minor salivary gland tumors, and sarcomas.

The most common minor salivary gland malignancies are adenoid cystic carcinoma, mucoepidermoid carcinoma (low and high grade), polymorphous low-grade adenocarcinoma, and adenocarcinoma. They may present as a painless, slow-growing, submucosal mass at the junction of the hard and soft palate. Adenoid cystic carcinoma can present with perineural invasion that can extend within the greater palatine nerve to the pterygopalatine ganglion and ascend to the skull base.

Sarcomas of the oral cavity usually arise in the mandible or hard palate and include osteosarcoma (Fig. 96-9), chondrosarcoma, malignant fibrous histiosarcoma, rhabdomyosarcoma, and liposarcoma. Patel and colleagues demonstrated a 5-year local control rate for head and neck osteosarcoma of 78% and overall survival of 70%. Patients presented with osteosarcoma within the maxilla and mandible with approximately equal frequency, 45% to 41%, respectively. Surgery was performed in all patients, and neoadjuvant chemotherapy was used in 68% of patients. Positive surgical margins were found to be the only significant negative predictor with respect to disease-specific survival.⁴³

Figure 96-9. Osteosarcoma specimen of the right hemimandible.

Kaposi’s sarcoma (KS) is the most common HIV-associated malignancy. The head and neck is the site for 63% of all presentations. KS may present as a mucosal or cutaneous lesion with a nodular or macular appearance and most commonly occurs on the hard palate. Despite being considered an incurable disorder, a variety of treatment options that may offer remission for limited disease are available. Local therapies include radiation, intralesional injection of chemotherapy, cryotherapy, alitretinoin gel, laser therapy, and surgical excision. Systemic chemotherapy is reserved for advanced disease.¹⁶

Desmoplastic neurotrophic melanoma is a nonpigmented lesion of the lower lip that presents as an ulceration and has a high incidence for perineural invasion. Mucosal melanoma typically presents as a pigmented lesion of the oral cavity that may be associated with preexisting melanosis. Pigmented lesions of the oral cavity should be considered for biopsy to exclude this diagnosis.⁴⁴

History and Physical Examination

A detailed history and physical examination are critical to the comprehensive evaluation of all head and neck cancer patients. When evaluating a patient for an oral lesion, inquiries into changes in the fit of a preexisting denture, otalgia, trismus, oral-dental pain, bleeding, halitosis, weight loss, dysphagia, odynophagia, dysarthria, and facial numbness should be made.

Patients should be questioned about specific medications, allergies, medical diagnoses, and previous surgical interventions. This information can be critical when formulating a treatment plan tailored to a patient’s comorbidities. In addition, a detailed history of the patient’s tobacco and alcohol use should be obtained.

The head and neck physical examination should allow for accurate staging of the tumor, assess the patient’s functional capacity before treatment, and include a careful search for synchronous upper aerodigestive tract cancers. The physician should evaluate the dimensions of the index lesion and the potential anatomy involved by direct spread of tumor (Fig. 96-10). The lesion should be palpated to assess for fixation to the underlying periosteum suggesting potential mandibular or maxillary involvement. Determination of midline extension, regional lymphatic spread, and the need for reconstruction should be considered. The appropriateness of specific donor sites for free and/or pedicled flap reconstruction should also be assessed.

Figure 96-10. Tongue deviation to the right with atrophy suggestive of cranial nerve XII involvement by a floor-of-mouth cancer with right submandibular lymphadenopathy noted at pretreatment evaluation.

At the initial evaluation, if tissue pathology has not been previously obtained, a punch biopsy of the perimeter of the primary tumor and/or FNA (potentially ultrasound-guided) of suspected regional metastases should be performed. If the patient underwent biopsy at an outlying site before consultation, the specimen should be obtained and reviewed with the pathologist at the surgeon’s facility to confirm the tissue diagnosis.

For patients with imaging already performed, films are reviewed for the extent of the primary disease and regional lymphadenopathy. Film quality, date of imaging, and need for supplemental imaging should be assessed. Before initiating treatment, the patient should be presented at a multidisciplinary tumor conference with representation by surgeons, radiation oncologists, medical oncologists, and reconstructive surgeons for a discussion of available treatment options.

Future screening for oral cancer may be possible with outpatient biomarker laboratory assays. St. John and colleagues⁴⁵ have described the use of an assay for salivary interleukin (IL)-8 and serum IL-6 with promising results in patients with oral cavity and oropharyngeal carcinoma.

Preoperative Assessment

Obtaining information that either confirms or alters the strategy of the operative intervention and assesses the patient’s overall readiness for surgery is necessary. Preoperative evaluation depends on the patient’s age and comorbidities. In most instances an electrocardiogram, chest x-ray, and basic laboratory profile should be obtained. Patients with a history of alcohol abuse should have a liver profile performed. For patients with significant comorbidities, the patient’s primary care physician or cardiologist should be included in the preoperative risk assessment.

Imaging to assess the primary extent of tumor and cervical lymph nodes includes either computed tomography (CT) or magnetic resonance imaging (MRI). CT is best for demonstrating cortical bone erosion and lymph node metastases. MRI is favored for demonstrating soft tissue invasion by tumor and extension into medullary bone. A Panorex may be obtained preoperatively in patients with suspected mandibular invasion and can assist dental evaluation. Dentascan imaging, using a dental CT-based software program, can be helpful in assessing the likelihood of mandibular invasion, with a reported sensitivity of 95%.⁴⁶ Goerres and colleagues noted the assessment of cortical invasion of the mandible was best assessed by conventional contrast-enhanced CT (as well as the CT component of PET-CT) with a sensitivity of 100% and accuracy of 97%.⁴⁷ The extent of imaging is frequently driven by physician preference and the complexity of the presenting lesion. Patients with T₁ lesions, without clinical lymphadenopathy, may not require extensive imaging to aid operative decision making.

Newer imaging modalities such as positron emission tomography (PET), PET-CT, single photon emission computed tomography (SPECT) scanning have been used to stage patients with head and neck cancer, but their role in preoperative assessment is not uniform and continues to evolve. Assessment for distant metastases may be performed using one of these modalities or via CT of the chest with contrast. Suspicion of distant metastases may require CT-guided biopsy for confirmation. Patients with distant metastases are not typically considered optimal candidates for curative treatment and may be better served by exploring palliative care options while preserving maximal quality of life.

Preoperative Interventions

Anticipating the nutritional needs of patients may prevent an extended need for hospitalization or treatment breaks during postoperative radiation. Malnutrition in the perioperative period can predispose patients to wound complications. Preoperative consultation for gastrostomy tube placement should be considered for those patients in which the ability to take oral nutrition is compromised before surgery or anticipated to extend for a prolonged period of time postoperatively. For those requiring postoperative radiation therapy, mucositis can result in a delay in the normal resumption of oral intake for several weeks to months.

In addition, dental evaluation is essential for patients with poor dentition and those who may require radiation as part of their treatment. Prosthodontic evaluation is indicated for those who will undergo maxillectomy and require a surgical obturator.

For patients with the potential for significant speech and swallowing impairment postoperatively, consultation and counseling with a speech-language pathologist can aid in long-term rehabilitation.

Endoscopy

Panendoscopy including bronchoscopy, esophagoscopy, and direct laryngoscopy has been advocated for the preoperative assessment of head and neck cancer patients. Given that the reported risk of harboring synchronous second lesion is between 5% and 10% in newly diagnosed patients, some consider panendoscopy necessary. Others advocate direct laryngoscopy but reserve performing esophagoscopy and bronchoscopy in symptomatic patients (with pretreatment dysphagia, odynophagia, cough, and/or hemoptysis) or if the preoperative thoracic imaging (chest x-ray or CT) is abnormal. If a percutaneous endoscopic gastrostomy tube placement is planned before definitive surgery, evaluation of the esophagus can be deferred to that procedure. Alternatively, a preoperative barium swallow can serve as a screening tool to exclude a second primary tumor; however, false-negative findings associated with the technique can occur. The extent of investigations for excluding second primary tumors is individualized according to physician preferences and the needs of an individualized patient.

Second Primary Tumors

Patients with smoking-related head and neck cancer are at risk for the development of a second primary tumor. A second primary tumor detected simultaneously or within 6 months of the initial primary tumor is defined as a synchronous lesion. Emergence of a second primary lesion more than 6 months after discovery of the index tumor is referred to as metachronous. The incidence and site of subsequent primaries vary depending on the site of the initial primary lesion.

The overall incidence for synchronous and metachronous lesions for patients diagnosed with a primary head and neck malignancy is approximately 14%. Of these malignancies, 80% are metachronous cancers with 50% of cases presenting within the first 2 years of initial treatment of the primary tumor. For patients with oral cavity and oropharyngeal malignancies, the site of a second malignancy is most frequently in the cervical esophagus. New symptoms of dysphagia or odynophagia in this patient population should prompt a diagnostic evaluation with barium swallow or esophagoscopy.⁶⁰ There appears to be a bimodal pattern for second primary tumors in the esophagus, with an early group developing tumors within 2 years of treatment of the index primary tumor and a later group that develops esophageal cancer greater than 5 years after primary treatment.⁶¹

Operative Approaches

The surgical approach to the oral cavity primary site is dictated by the size, location, and associated involved anatomy relative to the tumor’s presentation. Resection of limited (T1, small T2s) primary lesions can typically be performed transorally. Using transtumoral cuts, larger lesions can also be excised to a negative margin using the transoral approach. Advanced-stage oral tongue lesions, in particular those with posterior extension, may require a mandibulotomy-based approach to allow adequate access for the resection of the posterior margin of the tumor and allow for reconstruction. Advanced-staged tumors of the anterior oral tongue and floor of mouth, in particular those that involve the genioglossus and mylohyoid musculature (without mandibular involvement), can be efficiently managed with a visor or degloving approach. This approach can allow for excellent visualization enabling wide resection of the deeply invasive primary lesion while sparing the patient from a mandibulotomy and a possible postoperative nonunion. Specific considerations relative to the resection of various types of presentations at the different oral cavity sites are discussed as follows.

Lip

The majority of neoplastic lesions that affect this subsite present on the lower (88% to 95%) as opposed to the upper lip (2% to 7%) or the commissure (1%) (Fig. 96-11). For the lower lip, squamous cell carcinoma predominates, whereas basal cell carcinoma disproportionately arises on the upper lip. In addition to basal and squamous cell carcinoma, the differential diagnosis of a lip lesion includes keratoacanthoma, minor salivary gland tumors, malignant melanoma, and tumors of mesenchymal origin (malignant fibrous histiocytoma, leiomyosarcoma, fibrosarcoma, angiosarcoma, and rhabdomyosarcoma).

Figure 96-11. Squamous cell carcinoma of the lip at the oral commissure.

The typical patient with a squamous cell carcinoma of the lip is a male 50 to 70 years of age. Risk factors include prolonged exposure to sunlight, fair complexion, immunosuppression, and tobacco use.

Clinical findings in lip cancer usually include an ulcerated lesion on the vermilion or cutaneous surface or, less commonly, on the mucosal surface. The majority of patients present with early-stage lesions and without evidence of neck metastases.⁶⁴ A nodular or sclerotic lesion may infiltrate into the deeper tissues, and careful palpation is important for determining the actual size of the lesion. Minor salivary gland tumors present as a submucosal nodule on the inner surface of the lower lip. The presence of paresthesias or dysesthesias in the area adjacent to the lesion indicates possible mental nerve involvement.⁶⁵

Neck metastases are an infrequent finding with lower lip squamous cell carcinomas and occur in only 10% of cases. Lower lip lesions may metastasize bilaterally because of the communicating pattern of the lymphatics. An increased risk of regional metastasis is associated with commissure and upper lip lesions. Adverse prognostic features of lip primaries include perineural invasion, bony involvement, cancer arising on the upper lip or commissure, regional lymphatic metastasis, and age younger than 40 years at onset.⁶⁶ Lip cancer results in fewer than 200 patient deaths annually and is stage dependent. Diagnosed early and with adequate treatment, cure rates are high. Obtaining an adequate cosmetic result and functional outcome without microstomia can be challenging with advanced-staged lesions.

The surgeon should consider several factors when planning a resection and reconstruction for a patient with a lip carcinoma (Fig. 96-12). The typical lip length is 6 to 8 cm. Reconstructive algorithms are based on the proportion of lip resected. Realignment of the vermilion border during the reconstruction and preservation of the oral commissure (when possible) are important principles in attempting to attain an acceptable cosmetic and functional result.

Figure 96-12. Midline lower lip squamous cell carcinoma noted with ulceration extending to the vermilion border. Wedge resection with primary closure is planned.

Small primary lesions may be treated with surgery or radiation with equal success and acceptable cosmetic results. However, surgical excision with histologic confirmation of tumor-free margins is the preferred modality. The reconstruction of lip defects after tumor excision requires innovative techniques to provide oral competence, maintenance of dynamic function, and acceptable cosmesis. With small lesions, defects up to one third of the lip’s length, simple excision with primary closure is possible. When lesions require resection of up to one third to two thirds of a lip’s length, reconstructive options include a lip-switch (Abbe-Estlander) (Fig. 96-13) or a Johansson stepladder flap.⁶⁷ For tumors requiring resection of more than two thirds of the lip, the reconstructive options are the Gilles fan flap, bilateral advancement flaps, Karapandzic, or a free radial forearm with palmaris longus tendon. The Karapandzic flap (Fig. 96-14) is a sensate, neuromuscular flap that includes the remaining orbicularis oris muscle. The blood supply for this flap is the corresponding branches of the labial artery. Microstomia is a potential complication with these methods of lip reconstruction.⁶⁸ For large defects, Webster or Bernard procedures using lateral nasolabial flaps with buccal advancement have been described.⁶⁹ In addition, for aggressive and advanced-staged lesions, an evaluation for perineural spread should be performed at the time of resection. Potential biopsy of the mental nerve with a retrograde dissection in an attempt to obtain a negative margin should be considered. With extensive perineural invasion, a drill-out of the mental nerve or hemimandibulectomy may be required.

Figure 96-13. Abbe-Estlander flap for a left lower lip resection extending to the oral commissure. A, Wedge resection of lateral lower lip carcinoma. B, Initial mobilization of upper lip tissue preserving the commissure consistent with Abbe-Estlander flap reconstruction. C, Final inset of flap, arrows mark site of advancement and tension with closure.

(Adapted from Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

Figure 96-14. Karapandzic fan flap for midline lower lip defect. A, Rectangular-shaped full-thickness resection of lower lip carcinoma. B, Initial mobilization of circumoral advancement flaps, the neurovascular pedicle (inset on B) is preserved bilaterally. C, Final inset of reconstruction.

(Adapted from Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

The primary echelon of nodes at risk for metastatic spread is the submandibular and submental region. Diagnostic evaluation for potential nodal spread includes fine-needle aspiration with or without ultrasound or CT guidance. In the presence of clinically evident neck metastasis, therapeutic neck dissection is indicated. Unnecessary sacrifice of both facial arteries (when bilateral neck dissections are required) could have implications on the vascularity of facial structures used for a complex lip reconstruction. Elective neck dissection is not typically advocated for lip carcinoma because the incidence of occult metastases is low.

The 5-year survival for stage I and II lesions is 90%. For patients with cervical metastases, the survival decreases by 50%.⁶⁷ Patients with oral commissure and upper lip carcinomas have a worse overall prognosis when compared with similar tumors of the lower lip. Postoperative radiation therapy is considered for patients with close or positive margins, lymph node metastases, or perineural invasion.

Alveolar Ridge

Squamous cell carcinoma of the mandibular and maxillary alveolar ridges represents approximately 10% of all oral cavity cancers. Lower alveolar ridge carcinomas present more frequently than upper lesions.

In a review of 155 patients with lower alveolar ridge carcinoma, the mean age at presentation was 66.7 years. In this group, 63% of tumors were located over the mandibular body and 25% arose over the symphysis. More than half of all lesions were diagnosed in edentulous patients. The majority of patients (67%) were noted to have early-stage lesions (T₁/T₂).⁷⁰

Given that the mucosa closely approximates the underlying bone of the alveolus, osseous erosion and/or invasion at presentation is common. Tumors extending within adjacent dental sockets are associated with a higher likelihood of bone invasion. In this situation, preoperative radiographic evaluation can significantly aid in treatment planning. Close and colleagues⁷¹ noted that the CT scan was more sensitive and specific than the bone scan and Panorex in predicting mandibular invasion. The need to address periosteal and bone invasion may be seen in up to 50% of patients. With mandibular invasion, the inferior alveolar nerve may become secondarily involved by perineural invasion. Treatment options of marginal versus segmental mandibulectomy are dependent on whether the tumor invades the periosteum, cortical, or medullary bone (Fig. 96-15). When tumors approach but do not invade the periosteum, a subperiosteal resection with mandibular preservation is possible with primary closure or split-thickness skin graft reconstruction. When the periosteum is invaded, marginal mandibulectomy is indicated. Marginal resection may be performed in two planes. The classic “rim” or coronal marginal mandibulectomy removes the superior aspect of the involved mandible, whereas a lingual sagittal marginal mandibulectomy removes the lingual cortex of the mandible contacting the tumor (Fig. 96-16). With lesions surrounding intact dentition, extraction and alveolar resection are required to obtain an adequate margin. When the tumor extends down the tooth socket into the medullary bone, segmental mandibulectomy is frequently necessary. With segmental mandibular defects of the symphysis, reconstruction with vascularized free tissue transfer with an osseous flap remains the standard of care. For lateral mandibular defects, the options are more varied and may include primary closure, pedicled and/or vascularized free flap soft tissue reconstruction, or vascularized osseous free tissue transfer.

Figure 96-15. A, Atrophic appearance of an edentulous mandible. This demonstrates why marginal mandibulectomy is difficult to perform without iatrogenic fracture in these patients. B, Examples comparing a marginal versus segmental mandibulectomy.

(Adapted from Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

Figure 96-16. Cuts for a sagittal lingual marginal mandibulectomy at the symphysis.

(Adapted from Donald PJ. Head and Neck Cancer: Management of the Difficult Case. Philadelphia: WB Saunders; 1984.)

When extensive maxillary alveolar ridge cancers are encountered, potential extension into the nasal cavity and paranasal sinuses should be anticipated.

General guidelines for neck dissection with oral cavity malignancies in the N₀ patient include treatment of the neck when the risk of occult metastatic spread to the regional lymphatics exceeds 20%. Upper alveolar ridge tumors tend to regionally metastasize to jugulodigastric lymph nodes, whereas lower alveolar ridge tumors drain to submandibular lymphatics. Among patients with clinical evidence of lymphadenopathy (N⁺), regional treatment typically requires a modified radical neck dissection (levels I-V). Eicher and colleagues noted that levels IV and V harbored metastases in 20.9% of patients with inferior alveolar ridge cancer undergoing therapeutic neck dissection for clinically evident adenopathy. Patients undergoing elective dissection demonstrated occult metastases in levels I (53.3%), II (40%), and III (6.7%). Presence of an advanced T-stage (T₃, T₄) lesion and bony mandibular invasion have been correlated with the development of regional metastases. As such, elective neck dissection removing levels I to III is advocated for all advanced-staged primaries (T₃, T₄) and T₁-T₂ lesions at the mandibular symphysis or for tumors with moderate to poorly differentiated tissue pathology.⁷⁰ The overall risk of metastases with alveolar ridge carcinoma is 25%.^70,72 In patients with a clinically N₀ neck, occult metastases have been noted in 15% of operative specimens. The 2- and 5-year survival for patients with occult metastases who underwent END is better than for patients who underwent therapeutic neck dissection after the eventual development of metastatic adenopathy.⁷⁰

The 5-year survival ranges from 85% (T₁, T₂) to 65% (T₃, T₄) for patients without metastatic spread. Among patients with regional or distant metastases, the 5-year survival has been reported to range from 35% to 59%.^73,74 Decreased local control rates are seen with lesions greater than 3 cm and positive surgical margins. Significant prognostic factors include advanced T stage (T₃, T₄), margin status, mandibular invasion, and the presence of regional metastases. Neither local control nor survival are affected by the extent of mandibular resection, dental intervention near the site of the primary, perineural invasion, or histologic grade of the tumor.⁷² Postoperative radiation therapy is advocated for patients with T₄ tumors, positive margins, perineural invasion, and regional metastasis.^70,72

Oral Tongue

The oral tongue is a muscular structure with overlying nonkeratinizing squamous epithelium. The posterior limit of the oral tongue is the circumvallate papillae, whereas the ventral portion is contiguous with the anterior floor of mouth. Subsites include the lateral tongue, the anterior tip, the ventral tongue, and the dorsal oral tongue. Carcinomas of the tongue arise in the epithelium and invade into the deeper musculature. The most common presentation is that of a painful ulcerated or exophytic mass (Fig. 96-17).

Figure 96-17. Hemiglossectomy specimen demonstrating an ulcer along the lateral edge from a tumor invading toward the floor of mouth.

Oral tongue carcinoma typically presents in males with a history of tobacco and alcohol use in their sixth or seventh decade of life. The majority is squamous cell carcinoma and approximately 75% occur on the posterolateral aspect of the oral tongue. The second most common site (20% of lesions) is the anterolateral and ventral surface of the tongue. The direct contact of carcinogens from tobacco or other agents is considered causative in the development of cancer at this site. Tumors may present on the dorsal surface of the tongue; however, this represents a minority of lesions (3% to 5%). The differential diagnosis for dorsal lesions of the tongue is broad and should include amyloidosis, median rhomboid glossitis, granular cell myoblastoma, and erosive lichen planus. Because of the rarity of carcinomas of the dorsal tongue, a delay in diagnosis is not infrequent.⁷⁵ The differential diagnosis of submucosal oral tongue tumors is those derived from mesenchymal tissues including leiomyomas, leiomyosarcoma, rhabdomyosarcoma, and neurofibromas.

Local invasion by tongue carcinoma may progress by various routes depending on the site of origin. A tumor of the anterolateral tongue may spread medially across the central raphe to the contralateral side, posteriorly to the tongue base, and inferiorly into the suprahyoid muscles and the muscular “root” of the tongue. Lateral spread to involve a significant portion of the floor of mouth is not uncommon. The lingual and hypoglossal nerves may be invaded directly by tumors. Their involvement produces the clinical findings of loss of sensation of the dorsal tongue surface and deviation on tongue protrusion, fasciculations, and atrophy. In addition, the patient may complain of referred otalgia. The extreme of lateral tumor extension, beyond floor of mouth, includes direct invasion of the mandible, requiring composite resection (Figs. 96-18, 96-19, and 96-20).

Figure 96-18. Composite resection specimen of ulcerative tongue carcinoma with lateral extension into the floor of mouth and mandible. Posterior extent of resection includes the retromolar trigone and anterior tonsillar pillar.

Figure 96-19. Approach for a composite resection for a T₄ tongue squamous cell carcinoma invading the lateral mandible.

Figure 96-20. Hemimandibulectomy for posterior floor of mouth–lateral tongue tumor with associated modified radical neck dissection (type 1). Reconstruction options include soft tissue reconstruction of the deficit or osseous free tissue transfer.

At the time of diagnosis, the majority of oral tongue carcinomas (75%) are T₂ or smaller. The surgical treatment for limited, small (T₁ to T₂) primary tumors is transoral wide local excision. Frozen section confirmation of the margin status is necessary before pursuing reconstruction. Advanced-stage lesions that approach the mandible or invade into the deep musculature are best accessed via a pull-through or mandibulotomy technique. When a segmental resection is warranted, access to the oral cavity through the mandibulotomy cuts provides wide access to the primary tumor.

A partial glossectomy, which may remove a significant portion of the lateral oral tongue, can still permit reasonably effective postoperative function. However, treatment of larger tumors that invade deeply within the tongue can result in a significant functional impairment. With resection of approximately one quarter to one third of the oral tongue, healing by secondary intention is an acceptable option. If a limited portion of the floor of mouth is resected, reconstruction with a split-thickness skin graft should be used to prevent tongue tethering. Resection of approximately one half of the tongue results in loss of tongue bulk and scar contracture if limited reconstructive options are pursued. Lingual contact with the palate, lip, and teeth is decreased and can result in impaired articulation. Posterior propulsion of the food bolus and liquids may also be affected. The use of soft pliable fasciocutaneous free flaps such as a radial forearm or anterolateral thigh free flap can provide intraoral bulk and preservation of existing tongue mobility. A palatal augmentation prosthesis allows for contact between the remaining tongue tissue and the palate and may improve speech and swallowing function. For patients undergoing a partial glossectomy with a significant resection of the floor of mouth, free flap reconstruction to maintain tongue mobility is indicated.

Kurokawa and colleagues⁷⁶ noted that in patients with moderately differentiated squamous cell carcinoma of the oral tongue, tumor depth of invasion equal to or greater than 4 mm was associated with occult cervical lymph node metastases. Spiro and colleagues⁷⁷ demonstrated that increasing tumor thickness, and not T stage, correlated with treatment failure and survival. Disease-related death was uncommon for patients with depth of invasion less than 2 mm. The depth of invasion can be used to guide the necessity for elective neck dissection in N₀ patients with early-stage lesions.

At initial presentation, 40% of patients with oral tongue carcinoma demonstrate evidence of cervical metastases. For patients with T₁ and T₂ tumors with clinically N₀ neck examination, 20% to 30% of elective neck dissection specimens are pathologically positive. Byers and colleagues noted that 15.8% of lateral tongue carcinoma patients demonstrated “skip” metastases to lymph nodes, bypassing levels I and II, and presenting with level III or IV metastatic disease. They concluded that elective supraomohyoid neck dissection was inadequate for the control of regional lymphatics of oral tongue carcinoma patients and advocated for levels I to IV neck dissection in this situation.⁷⁸ When lesions approach the midline, the likelihood for bilateral regional metastasis is high and requires bilateral lymphadenectomy.

Patients with advanced-stage lesions (III or IV) require surgery and postoperative radiation therapy to achieve the best locoregional control rates. Franceschi and colleagues noted an increase in locoregional control for stage III and IV patients from 57% to 71% with the addition of postoperative radiotherapy. In this study the only factor predictive of locoregional recurrence was a positive surgical margin. The majority of patients (78%) recurred within 2 years.⁷⁹ Among patients developing a local recurrence, attempts at surgical salvage to control disease are frequently unsuccessful.

The 5-year survival for stage I or II tumors is 75% and less than 40% for stage III or IV tumors.^79,80

Retromolar Trigone

The majority of patients with retromolar trigone carcinomas tend to present with advanced disease. At the time of presentation, up to 50% of patients present with regional metastatic disease. Mandible involvement is common given the thin layer of soft tissue separating these tumors from the ascending ramus. Trismus suggests involvement of the medial pterygoid muscle. As tumors progress in this location, extension to the faucial arch, tonsillar fossa, and the base of the tongue is common. In addition to squamous cell carcinoma, the differential diagnosis of lesions in this region includes minor salivary gland neoplasms, osteosarcoma, and soft tissue sarcomas.

Given the proximity of the mucosa to the underlying ramus of the mandible, surgical resection of early-stage retromolar trigone lesions may require a resection of a portion of the mandible. Treatment options include an L-shaped coronal marginal mandibulectomy, segmental mandibulectomy, and hemimandibulectomy. With the L-shaped marginal mandibulectomy, the superior aspect of the body—extending toward the angle and ascending the ramus—is resected (Figs. 96-21 and 96-22). Segmental mandibulectomy is performed for more extensive lesions with gross bone destruction.

Figure 96-21. Postresection appearance after L-shaped marginal mandibulectomy for a posterior alveolar ridge–retromolar trigone squamous carcinoma.

Figure 96-22. L-shaped marginal mandibulectomy for a retromolar trigone tumor. A generous portion of cortical bone remains at the posterior body-angle-ramus of the mandible such that the defect requires only soft tissue reconstruction. A, Planned approach for marginal mandibulotomy with wide local incision for retromolar carcinoma without gross bony invasion. B, Appearance after surgical resection of tumor prior to reconstruction revealing medial pterygoid and deep tongue musculature.

(From Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

Huang and colleagues demonstrated a 5-year, disease-free survival for T₁ lesions of 76%, which declined to 54% for T₄ disease. Patients with N₀ disease had a 5-year survival of 69%. Survival fell to 56% for those who were N₁ and to 26% for patients with N₂ disease. The recurrence rate for patients treated with radiation therapy alone was 44% compared with 23% for patients undergoing surgical resection with postoperative radiation therapy. Complications reported in patients undergoing treatment with radiation included osteoradionecrosis, soft tissue necrosis, or severe trismus.⁸¹

Floor of Mouth

Carcinomas of the floor of mouth typically present in males in their sixth decade of life. Approximately 35% of these patients present with an advanced T-stage (T₃, T₄) lesion on initial diagnosis.⁵⁰ The floor of mouth musculature plays an important role in the modes of tumor spread. The floor of mouth is composed of the slinglike genioglossus, mylohyoid, and the hyoglossus muscles, which serve as a barrier to the spread of disease. Invasion into these muscles can lead to tongue hypomobility and dysarthria. In addition, tumors of the anterior floor of mouth may extend posteriorly into the ventral aspect or “root” of the tongue, causing fixation.

Deep invasion into the intrinsic musculature of the tongue causes fixation and mandates a partial glossectomy in conjunction with resection of the floor of mouth. Lesions in the anterior floor of mouth may directly invade the sublingual salivary gland or submandibular duct and require in-continuity resection with the primary lesion. Direct extension of tumors through the sublingual space into the submaxillary space indicates the need for an in-continuity resection of the primary tumor and neck.

Anterior or lateral extension to the lingual aspect of the mandible is of primary importance in preoperative treatment planning for these lesions. Imaging studies of the mandible including CT, MRI, and Panorex are useful in conjunction with careful clinical evaluation by bimanual palpation to ascertain adherence to the mandible. The absence of fixation of the lesion to the inner mandibular cortex indicates mandible-preserving techniques are feasible.

The treatment of choice for early-stage lesions, not involving the mandible, is transoral resection. For more extensive anterior and lateral floor of mouth cancers without mandibular involvement, a pull-through technique can spare the need to perform a mandibulotomy. Paramedian or lateral mandibulotomy is seldom necessary except for some posterior floor of mouth tumors. The resection of larger tumors of the floor of mouth usually requires immediate reconstruction. The goals of reconstruction are to obtain a watertight closure to avoid salivary fistula and preserve tongue mobility. For extensive mucosal and soft-tissue deficits, the radial forearm free flap offers the best reconstructive option to accomplish these goals. Additional reconstructive options include the nasolabial, platysma, and pectoralis major flaps. The platysmal flap can be used for small lateral defects, whereas the pectoralis major myocutaneous flap can be used for larger soft tissue defects, preferably when the posterolateral mandible is resected.

For lesions without evidence of bony invasion but demonstrating involvement with the lingual periosteum, a coronal partial mandibulectomy may be required (Fig. 96-23). For massive lesions associated with mandibular destruction, composite resection with segmental mandibulectomy is necessary (Fig. 96-24).

Figure 96-23. Anterior floor of mouth carcinoma treated with a marginal mandibulectomy with a visor flap approach. Teeth are extracted at the sites of the osteotomy cuts. A, Anterior view of marginal mandibulectomy approach with wide local excision for floor of mouth carcinoma. B, Sagittal view demonstrating bone and soft tissue cuts superficial to the geniohyoid and mylohyoid muscles.

(From Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

Figure 96-24. Composite resection of floor of mouth carcinoma with segmental mandibulectomy. To obtain wide surgical margins, a significant portion of lateral oral tongue is resected with the specimen.

(From Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

Cervical metastases are noted in approximately 50% of patients with floor of mouth carcinoma. The submandibular lymph nodes (level IB) are most frequently involved.⁵⁰ Bilateral metastases are common with lesions of the anterior floor of mouth.

The 5-year survival for carcinomas of the floor of mouth are 90% for stage I, 80% for stage II, 65% for stage III, and 30% for stage IV disease.^50,82

Buccal Mucosa

Carcinomas of the buccal mucosa represent 5% to 10% of all oral cavity malignancies (Fig. 96-25). There is a 4 : 1 male predominance and the typical patient is in the sixth decade of life. An association between smokeless tobacco use and buccal carcinomas has been noted. An increased incidence of these tumors is seen in the Southeastern U.S. population. In India, betel nut use is associated with a high incidence of buccal carcinoma.

Figure 96-25. Ulcerated buccal mucosal lesion in a patient with oral pain and trismus noted to be squamous cell carcinoma at biopsy.

Verrucous carcinoma usually arises on the buccal mucosa and is considered a low-grade malignancy. Poor oral hygiene, tobacco use, and viral infection have all been suggested as potential etiologies. Although considered low grade, foci of invasive carcinoma and areas of dedifferentiation may be found within an individual specimen. Surgical resection is the treatment of choice.⁸³ Elective treatment of the regional lymphatics is not necessary given the low likelihood of regional metastasis. The differential diagnosis for epithelial-based lesions presenting in the buccal mucosa should also include squamous papilloma and pseudoepitheliomatous hyperplasia. Minor salivary gland tumors may also present as a submucosal mass within this region.

The site of the buccal mucosa where squamous carcinomas are most frequently noted is adjacent to the third mandibular molar. Patients with advanced-staged disease may present with trismus as a result of direct invasion of the tumor into the muscles of mastication. Parotid duct involvement may produce obstructive sialoadenitis. Anterior lesions metastasize regionally to submandibular nodes, whereas posterior buccal lesions metastasize to upper jugulodigastric lymph nodes.

Small lesions can be excised transorally. Intermediate-staged primary tumors may be resected transorally or through a lip-splitting incision. With the exception of superficial lesions, the buccinator muscle should be resected in continuity, thus providing an adequate deep margin. Although primary closure or healing by secondary intention is acceptable for small primary tumors, larger defects should be repaired with a fasciocutaneous flap to avoid scar contracture and trismus, which are frequent sequelae of skin grafting. Local intraoral spread may necessitate resection of the alveolar ridge of the mandible or maxilla. For invasive squamous cell carcinomas and minor salivary gland tumors, the buccinator muscle should be included with the specimen at the time of resection. Deep invasion into the cheek may require through-and-through resection (Figs. 96-26, 96-27, and 96-28). Ideal reconstruction to provide both internal and external lining is best accomplished with a folded fasciocutaneous free flap. Surgery as a primary modality is advocated for buccal carcinoma, whereas combination therapy is advised for advanced lesions. As with most lesions of the oral cavity, tumor thickness has a direct correlation to prognosis. In T₁/T₂ N₀ tumors, depth of invasion greater than 5.17 mm at the primary site has been correlated with a risk of ipsilateral regional lymphatic spread.⁸⁴

Figure 96-26. Medial aspect of the extensive buccal carcinoma requiring partial maxillectomy and hemimandibulectomy. Crater from the ulcerative lesion extends anterior to the oral commissure and posteriorly to the retromolar trigone.

Figure 96-27. Lip-splitting approach extended into neck dissection incision for access to perform a hemimandibulectomy for a T₄ buccal carcinoma.

Figure 96-28. Closure of “through-and-through” buccal carcinoma accomplished with a cervicofacial advancement flap and pectoralis major flap. A portion of the pectoralis major flap lines the oral cavity, a portion is desquamated to transition externally, and a portion is external at the oral commissure extending to the advancement flap.

Diaz and colleagues reviewed a series of 119 (previously untreated) patients with buccal carcinoma undergoing treatment at the MD Anderson Cancer Center. Primary tumors were staged as follows: T₁—21%, T₂—38%, T₃—23%, and T₄—15%. The majority of patients (72%) were N₀ at presentation. The majority of patients were treated exclusively with surgery (71%). No patients were treated with radiation therapy alone, and postoperative radiation therapy (dosage 50 to 60 Gy) was used for patients with extracapsular nodal spread or positive margins. Transoral excision was performed in the majority of patients with only 27% of patients requiring a lip-splitting incision and cheek flap for resection. Modified radical neck dissection was performed for patients with N₊ necks, and supraomohyoid neck dissection was used for those with N₀ necks. The 5-year survival for all patients within the series was 63%. Five-year survival declined from 70% for N₀ patients to 49% for patients with metastatic lymphadenopathy. Within the series of patients, 45% experienced recurrence (23% local, 11% regional, 9% local and regional) and salvage therapy was successful in only 22%. Stensen’s duct involvement and buccinator muscle invasion had no effect on locoregional recurrence.⁸⁵

Reported 5-year survival is 75% to 78% for stage I, 65% to 66% for stage II, 30% to 62% for stage III, and 20% to 50% for stage IV disease.^82,85,86

For patients who are not considered appropriate candidates for extensive surgical resection and reconstruction, primary radiation or chemoradiation is a viable treatment option. The reported results on the use of primary radiation therapy in patients with locally advanced disease demonstrate high recurrence rates (45%) and compromised overall survival (38%) after treatment.⁸⁷

Hard Palate

Squamous cell carcinoma is the most common malignancy of the palate (Fig. 96-29). A close second in frequency are minor salivary gland tumors that include adenoid cystic carcinoma, mucoepidermoid carcinoma, adenocarcinoma, and polymorphous low-grade adenocarcinoma.⁸⁸ Mucosal melanoma most commonly arises on the hard palate and the maxillary gingiva and presents as a nonulcerated, pigmented plaque. The typical patient is 40 to 50 years of age, and the prognosis is poor because of the locoregional aggressiveness of the tumor and propensity for distant metastases. Kaposi’s sarcoma of the palate is the most common intraoral site for this tumor.⁸⁹ Chronic irritation from ill-fitting dentures may also play a causal role in the development of dysplasia. Inflammatory lesions arising on the palate may mimic malignancy and can be differentiated by biopsy. Necrotizing sialometaplasia appears on the palate as a butterfly-shaped ulcer and resembles a malignancy. Treatment is symptomatic and biopsy confirms its benign nature. Torus palatini are exostoses or bony outgrowths of the midline palate and maxillary bone that do not require surgical treatment unless patients are symptomatic.

Figure 96-29. Hard palate squamous cell carcinoma extending over the upper alveolar ridge to the gingivobuccal sulcus. Margin control for this tumor would extend to the soft palate posterior and require an infrastructure maxillectomy. Retrograde spread along the greater palatine nerve could result in skull base extension.

The typical patient with a carcinoma of the hard palate is an elderly male with a history of tobacco use. A high incidence of hard palate carcinoma is seen in countries where reverse smoking is practiced.

Minor salivary gland tumors typically present as a submucosal nodule. Ulceration is rare unless a biopsy has been previously performed. Minor salivary gland tumors tend to arise at the junction of the hard and soft palate. Direct infiltration of bone may lead to extension into the floor of the nose or the maxillary antrum. Neurotropic spread along the greater palatine nerve may result in extension to the foramen rotundum or CN V ganglion.

Squamous carcinoma of the hard palate is treated surgically. Small lesions may be treated with transoral wide local excision. The resection may be performed to the level of the bony portion of the hard palate with anticipated re-epithelialization. Because the periosteum of the palatal bone acts as a barrier to spread, excision with bony preservation is adequate for small lesions. Involvement of the periosteum requires removal of a portion of the bony palate. Partial or subtotal maxillectomy is required for larger lesions or those involving the maxillary antrum (Fig. 96-30). For malignancies extending along the greater palatine nerve, biopsy of this nerve is important for identifying neurotropic spread. Small- to medium-sized defects may be reconstructed with the aid of local advancement flaps or a buccal fat pad flap. Oronasal postresection fistulas of the palate require a dental prosthesis for rehabilitation of speech and swallowing. For lesions resulting in a palatal defect after resection, prosthetic rehabilitation can offer the patient an excellent functional result. In this circumstance a maxillofacial prosthodontist may construct a splint preoperatively for use at the time of resection. A split-thickness skin graft is used to cover edges of bone from osteotomy and replace sites within the sinuses where mucosa was removed as part of the resection. The cavity is then packed with petroleum gauze, and a lag screw can be used to secure the prosthesis to the maxilla, providing support to the underlying repair (Figs. 96-31, 96-32, and 96-33). The temporary prosthesis is removed approximately 1 week later and the packing is evacuated. An interim prosthesis is worn until a more permanent option can be tailored to the resultant defect.⁹⁰ Adjuvant radiation is indicated for advanced staged tumors, perineural invasion, and positive margins.

Figure 96-30. Bone cuts on an infrastructure maxillectomy for a hard palate malignancy.

(From Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

Figure 96-31. Hard palate squamous cell carcinoma before resection.

Figure 96-32. Approach to resection of a hard palate tumor. Weber-Ferguson incision with lip-split is shown for superoanterior exposure. Resection exposes the inferior aspect of the nasal cavity and maxillary sinus to the oral cavity. A, Planned cuts for resection of lateral maxillary alveolus and palate. B, Post-resection defect prior to reconstruction demonstrating communication with the lower aspect of the maxillary sinus.

(From Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

Figure 96-33. Obturator in place after infrastructure maxillectomy. Split-thickness skin graft covers the osteotomy margins and relines the maxillary sinus cavity and is held in place by petroleum gauze supported by the obturator.

Primary radiotherapy has been investigated as a therapy for hard palate carcinomas with an 80% 5-year local control rate reported for T₁ and T₂ tumors; however, this control rate falls to 24% for T₃ and T₄ lesions. Nevertheless, surgery is the favored primary modality for carcinoma of the hard palate. In this study, 5-year survival was 48% for squamous cell carcinomas and 63% for minor salivary gland carcinomas.⁹¹

For patients with hard palate malignancies, 10% to 25% present with cervical metastases, most frequently to the submandibular and upper jugular cervical nodes.⁹² Given the low incidence of occult metastases, elective neck dissection is not indicated in most cases.

The reported 5-year survival for patients ranges from 40% to 60%.^92,93

Surgery—Treatment of the Mandible

The management of the mandible as it applies to oral cavity malignancies has evolved over time. Initially, squamous cell carcinoma of the oral cavity was believed to invade the mandible through the adjacent lymphatics. Direct invasion is now recognized as the most common pathway. In a paper by Marchetta and colleagues in 1971,⁹⁴ it was demonstrated that tumors involve the mandible by first invading the periosteum. When the periosteum was free of direct tumor invasion, a mandible-sparing operation was considered feasible.

Mandible-sparing procedures including vertical and horizontal marginal mandibulectomy (Fig. 96-34) and pull-through techniques have gained popularity as organ conservation philosophies have emerged within the field (Figs. 96-35 and 96-36). In addition, pull-through techniques offer the advantage of avoiding a lip-splitting incision and allow adequate exposure for free tissue reconstruction. A pull-through is contraindicated in patients with gross mandibular destruction but may be performed in continuity with resection of the lingual plate of the mandible.

Figure 96-34. A, Floor of mouth tumor removed with a lingual sagittal marginal mandibulectomy. B, Floor of mouth–alveolar ridge tumor removed with a coronal “rim” marginal mandibulectomy.

Figure 96-35. Pull-through technique for extensive floor of mouth carcinoma extending into the oral tongue.

Figure 96-36. A, Floor of mouth tumor. B, Proposed pull-through approach. After raising the apron flap superiorly, the mylohyoid and anterior belly of the digastric are detached, allowing the delivery of the tumor for resection to a cervical location and sparing the need for mandibulotomy for selected lesions.

Mandibulotomy for access in oncologic resection and reconstruction of oral cavity malignancies is typically reserved for advanced-stage primaries with extensive oropharyngeal spread. Placement of the osteotomy in the midline or paramedian locations (with mental nerve preservation) is the preferred site. The paramedian mandibulotomy offers the advantage of ipsilateral geniohyoid and genioglossus muscle preservation, whereas midline osteotomy requires transection of these muscles. At times, sacrifice of a mandibular incisor or canine tooth may be required to perform an osteotomy. Creation of a mild to moderate malocclusion, independent of technique, has been shown to be a common finding.⁹⁵ With the bone cut for the mandibulotomy, loss of a fine column of cortical bone occurs. This can be lessened by partially sawing through the lingual cortex and greenstick fracturing the posterior table with an osteotome. Placement of a titanium plate before actual osteotomy is a strategy that will allow for retention of the patient’s normal occlusion when the mandible is reapproximated at the end of the procedure. The placement of drill holes for the plate at the inferior aspect of the mandible in patients with intact dentition avoids iatrogenic tooth root injury. If a lag screw technique is used, care needs to be exercised to avoid overcorrection with fixation of the mandibulotomy ends and creation of a malocclusion. Lateral mandibulotomy, at the level of the body or ramus, should be avoided because of poor healing at the osteotomy site and the interruption of the inferior alveolar artery and nerve at the time of osteotomy.

Complications from mandibulotomy have been extensively reported in the literature and range from 23.2% to 47.6%.^96,97 These include plate exposure, lip contracture, ankyloglossia, cellulitis-abscess, temporomandibular joint dysfunction, nonunion, and osteoradionecrosis. When mandibulotomy is performed in the setting of a marginal mandibulectomy, the risk of nonunion and infection associated with devascularization of the involved mandible has led some surgeons to abandon combining the two techniques.⁹⁶ Eisen and colleagues examined the morbidity of midline mandibulotomy in patients requiring postoperative radiation therapy. They found a complication rate of 11% in patients whose mandibulotomy site was included in the radiation field.⁹⁸

Assessing the need for segmental mandibulectomy can be a difficult treatment decision to make (Table 96-3). Although gross mandibular invasion clearly mandates a segmental mandibulectomy, situations in which periosteal adherence and subtle cortical invasion are suggested (by clinical examination or radiographic imaging) require the experience and judgment of the surgeon as to whether to proceed with a marginal mandibulectomy versus segmental mandibular resection. Marginal resection in the setting of alveolar ridge carcinoma has been advocated by some authors when radiographically detected bony erosion fails to extend below the level of the mandibular canal.⁹⁹

Table 96-3 Indications for Surgical Treatment of the Mandible

Segmental resections of the anterior mandible (including the symphyseal and parasymphyseal regions) mandate reconstruction with vascularized bone and soft tissue. Posterior segmental mandibular defects, in particular in edentulous patients or individuals with comorbidities limiting the ability for free tissue bony reconstruction, may be adequately repaired with soft tissue reconstruction only. Although the resection without bony reconstruction of the lateral mandible leaves patients with a J-shaped mandibular “swing,” speech and swallowing function are generally good and patients are capable of decannulating if tracheostomy is performed at the time of procedure. Cosmetic asymmetry consistent with a concavity in the region of the mandibular ramus is notable. Chin drift may occur without the opposing aspect of mandible but can be reduced if a bulky soft tissue flap (e.g., pectoralis major) is used for reconstruction of the posterior mandibular site. Alternatively, the lateral mandibulectomy defect can be spanned with a titanium mandibular reconstruction plate to maintain the continuity of the mandible, maintain occlusion, and avoid the chin drift observed from allowing the mandible to “swing.” This type of reconstruction should be done in combination with intraoral soft tissue reconstruction using a pedicled musculocutaneous flap (e.g., pectoralis major flap).

Surgery—Treatment of the Neck

Patterns of spread from primary tumor sites in the head and neck to cervical lymphatics are well described. The location and incidence of metastasis vary according to the primary site. Primary tumors within the oral cavity and lip typically metastasize to the nodes in levels I, II, and III (Fig. 96-37).

Figure 96-37. Levels of the regional lymphatics of the neck.

(Adapted from Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

The need to perform a neck dissection in the N₀ patient has undergone considerable investigation. Lymphoscintigraphy with sentinel node biopsy in the setting of the N₀ oral carcinoma patient has been reported to have a negative predictive value of 100%.¹⁰⁰ Even in previously treated oral carcinoma patients, sentinel node biopsy has a high reported negative predictive value (91%).¹⁰¹ Although initial results appear promising, most reported series reflect the experience of only a limited number of patients. Sentinel node biopsy is not currently considered standard of care for oral cavity carcinoma. Myo and colleagues reported on the use of cyclin D1 gene numeric aberrations assessed on FNA samples in stage I and II oral cancer patients. Cluster-type amplification of the cyclin D1 gene correlated with future regional recurrence in patients when the neck was not treated electively.¹⁰²

For a patient with an oral cavity malignancy who is clinically and radiographically N₀, with a risk of occult metastases exceeding 20%, many consider elective treatment to the regional lymphatics necessary. Options for treatment of the regional lymphatics include elective neck irradiation versus neck dissection.^103,104 With time, modifications of neck dissection have evolved from radical neck dissection through modified radical neck dissection to selective neck dissection. Surgeons have traditionally treated the N₀ neck with surgery.¹⁰⁵ Selective neck dissection can serve as a staging procedure to determine the need for postoperative adjuvant radiotherapy. For the clinically N⁺ neck, the surgical treatment of choice has traditionally been modified radical neck dissection (MRND) or radical neck dissection (RND), although some authors advocate selective neck dissection (SND) for the treatment of limited N₁ disease.¹⁰⁶ Kuntz and Weymuller examined quality-of-life data for patients undergoing RND, MRND, and SND. Shoulder disability at 6 months was the least for SND patients and similar for SND and MRND patients at 12 months. Additionally, MRND and SND patients were noted to have fewer problems with pain than RND patients.¹⁰⁷

The most common selective neck dissection performed for the management of the regional lymphatics in patients with oral cavity cancers is the supraomohyoid neck dissection (SOHND), which includes removal of lymph node levels I, II, and III. The reported incidence of regional recurrence after elective SOHND is as low as 3%.¹⁰⁸ Inclusion of level IIb nodes within the neck dissection is advocated for oral cavity primaries because of a reported 10% incidence of spread to this region¹⁰⁹; however, some authors disagree that the inclusion of level IIb is necessary in the setting of elective neck dissection.¹¹⁰ The occurrence of skip metastases with oral tongue lesions makes possible the involvement of nodes in levels III or IV without involvement of higher echelons of levels I or II. Byers and colleagues⁷⁸ noted that patients with lateralized oral tongue squamous cell carcinoma with an ipsilateral N₀ neck had a 15.8% rate of “skip metastases.” As a result, Byers and colleagues advocated a level I to IV neck dissection rather than a standard supraomohyoid neck dissection for patients with oral tongue carcinoma and an N₀ neck. Level V nodes are involved in some cases and are seen with concomitant involvement of higher echelon nodes.¹¹¹ Midline lesions have a high incidence of bilateral spread to cervical lymphatics and treatment of both necks is indicated in these scenarios. When considering the routes of spread, extensive hard palate lesions must be viewed with concern. Given the predilection for retropharyngeal spread of soft palate tumors, hard palate lesions with posterior extension should be considered for postoperative radiation therapy to address this region that might otherwise go untreated with standard neck dissection. For all sites, the actual presence of cervical metastasis has a negative impact on survival and, as such, aggressive preoperative investigation and close follow-up for head and neck cancer patients is necessary.¹¹²

Sentinel node biopsy, as it is currently applied for skin malignancies, has been explored for early-stage (T₁–₂N₀) lesions of the oral cavity through the American College of Surgeons Oncology Group (ACOSOG). With the exception of floor of mouth tumors, promising initial results (with negative predictive values >95%) have been reported. Additional investigation of the technique will be required before it is considered standard of care for this clinical scenario.

The decision for surgery versus radiation therapy for treatment of the neck is determined by the modality of treatment chosen for the primary tumor. If the primary tumor is treated with surgery, the neck is generally managed surgically. If the primary tumor is treated with radiation, then the neck is treated similarly.¹⁰⁵ For advanced cervical lymphatic disease (N₂, N₃) or metastasis with extracapsular spread, surgical management of the neck alone is inadequate and postoperative adjuvant radiation therapy is necessary.

Surgically debulking of metastatic disease does not improve survival and is not advocated. Surgical salvage for recurrent neck disease after comprehensive neck dissection or radiation is associated with poor survival.¹¹²

Radiation

Brachytherapy

Brachytherapy catheter placement for localized radiation boost has a limited role in the treatment of oral malignancies. Brachytherapy has been used for oral tongue and floor of mouth cancers surgically resected with close surgical margins on final histopathologic interpretation. Intraoperative placement is necessary and tracheostomy may not be required (Fig. 96-38). Loading of the catheters occurs within a hospital setting in a protected room after placement. The use of brachytherapy does require a prolonged hospital stay compared with standard surgical treatment requirements. Brachytherapy as a primary treatment has not been advocated because of the creation of post-treatment fibrosis limiting monitoring for recurrence of disease, as well as the risk of post-treatment ORN.

Figure 96-38. Brachytherapy catheters in place for oral tongue carcinoma resected with narrow surgical margin on final pathology after radial forearm free flap reconstruction.

Adjunctive Chemotherapy

Induction chemotherapy has been advocated to decrease the magnitude of resection; however, clinical trials supporting this approach are lacking. Induction (neoadjuvant) chemotherapy is not currently considered standard of care and potentially delays the timing of the definitive therapeutic procedure. Robbins and colleagues have reported on the use of a neoadjuvant RADPLAT protocol (intra-arterial infusion of cisplatin and intravenous infusion of sodium thiosulfate with concurrent radiation therapy to 50 Gy) in the setting of T₂ and T₃ oral carcinomas with varying levels of N staging. Surgery was described as a tumor nidusectomy performed after 8 weeks of therapy. Completed response was noted in 80% of the primary sites and 79% of the regional lymphatic fields. Five-year disease-specific survival rate was 64%, with a locoregional control rate of 74%.¹¹⁶

Increased survival with postoperative methotrexate and 5-fluorouracil (5-FU) has been demonstrated in patients with extracapsular nodal spread.^117,118 Evidence suggests a response to chemotherapy is predictive of the likelihood of response to radiation therapy.^119,120

Cooper and colleagues examined patients at high risk for locoregional recurrence that would benefit from the concurrent addition of cisplatin to postoperative radiation. High-risk patients were identified as having two or more metastatic lymph nodes, presence of extracapsular nodal spread, or positive surgical margins. In reviewing trial data from the Radiation Therapy Oncology Group (RTOG) #85-03 and RTOG #88-24, a benefit in locoregional control was suggested in the concomitant chemoradiation patients defined as “high risk” as opposed to those who received postoperative radiation alone. A difference in survival benefit was not seen between the two groups; however, factors such as lack of adequate randomization, limited group size, and length of follow-up were sited as reasons necessitating additional study.¹²⁰

The role of induction polychemotherapy followed by radiotherapy or chemoradiotherapy for advanced-stage squamous cell cancer of the oral cavity, oropharynx, hypopharynx, or larynx has recently been reported in two randomized, phase three clinical trials. The European study (EORTC 24971/TAX 323) compared docetaxel, cisplatin, and fluorouracil (TPF) to cisplatin and fluorouracil (PF) as induction chemotherapy followed by radiation therapy for patients with previously untreated, unresectable squamous cell carcinoma.¹²¹ Patients in the TPF group demonstrated a significant improvement in progression-free and overall survival as compared with patients in the PF group. A similar study by Posner and colleagues¹²² (TAX 324) compared induction chemotherapy with TPF or PF followed by concomitant chemoradiotherapy with weekly carboplatin. The study population included previously untreated patients with either unresectable disease or advanced-stage disease where organ preservation therapy was being considered. The results were similar to the TAX 323 study, with patients receiving TPF demonstrating a significant improvement in progression-free and overall survival. Unfortunately, neither study included a control group of chemoradiotherapy alone for comparison to the induction chemotherapy group.

Additional Therapies

Indications for Free Flap Reconstruction

Pectoralis major pedicled flaps and microvascular soft tissue reconstruction allow for the correction of the mucosal and soft tissue defects associated with tumor resection. For full-thickness buccal defects and extensive glossectomy defects, the pectoralis major flap can be partially de-epithelialized or rotated back on itself to provide resurfacing of the oral cavity components and the external lower one third of the face. However, the optimal treatment for many of these complex defects often requires microvascular free tissue reconstruction. The radial forearm free flap allows for a reconstruction that is tailored in shape to the oral defect without the burden of excessive bulk; offers the option for neural anastomosis, thus providing sensate reconstruction; and is associated with a limited donor site morbidity. When additional soft tissue is required, the anterolateral thigh,¹³⁷ rectus, and parascapular-scapular flaps may be harvested with larger skin paddles and associated muscle for additional bulk.

As discussed earlier in this chapter, reconstruction of the mandible depends on the location of the defect. In a review of their experience, Urken and colleagues reported on 210 cases requiring mandibular reconstruction. The need for segmental mandibulectomy was necessary for the treatment of benign and malignant tumors of the oral cavity and in the management of stage III osteoradionecrosis. They compared four groups of patients that included those reconstructed with iliac crest, patients who were not reconstructed (lateral defects), normal denture wearers, and normal dentate patients. The study demonstrated that speech and swallowing function were determined by the soft tissue reconstruction. Bite force was best if osteointegrated implants were achieved in patients with bony reconstructions. In addition, oral competence was improved with reconstructed patients.¹³⁵

Indications for a fibula osteocutaneous free flap reconstruction include total-subtotal mandibular reconstruction, reconstruction of “bone-only” defects (osteoradionecrosis), reconstruction of the atrophic mandible, pediatric mandibular reconstruction, and secondary reconstruction of the subcondylar-condylar complex (Fig. 96-40).¹³⁵

Figure 96-40. Fibular free flap reconstruction of the segmental mandibular defect and of the soft tissue defect of the floor of mouth and tongue. Vessel anastomosis is noted in the neck.

(Adapted from Silver CE, Rubin JS. Atlas of Head and Neck Surgery. 2nd ed. New York: Churchill Livingstone; 1999.)

Patients with advanced-staged complex primary lesions often present reconstructive dilemmas. For defects requiring additional soft tissue reconstruction, double free-tissue transfer with a soft tissue flap and an osseous flap have been advocated.¹³⁵ A scapular composite flap offers the advantage of multiple skin paddles with bone.¹³⁸ In addition, the presence of a musculoskeletal abnormality of the lower extremities may preclude a fibular free tissue transfer. Use of two microvascular free flaps, the fibula free flap combined with radial forearm free flap, has also been described to accomplish a reconstruction consistent with the needs of the specific defect. When external skin resurfacing is necessary, a cervicofacial advancement flap is a desirable option to consider in combination with a separate intraoral reconstructive technique.

Reconstructive options for composite resections of the oral cavity are dependent on location and the functional status of patients. An anterior mandibular defect in a healthy young patient is viewed differently than a lateral mandibular defect in a deconditioned elderly patient with poor dentition. Despite technical feasibility, not every patient requires free flap reconstruction to attain the postoperative goals of adequate speech and effective swallowing. An understanding of a patient’s expectations and an understanding of the attainable reconstructive results, while using the support of prosthodontists and speech and swallowing therapists, can create an atmosphere for successful rehabilitation.

Speech and Swallowing

To achieve the optimal functional outcome, it is important that the speech and swallowing therapist evaluates the patient before treatment. Preoperative consultation will provide an assessment of the patient’s pretreatment functional status and allow counseling concerning the potential functional outcome after treatment. The educated patient has more realistic expectations with respect to dysphagia, nutritional supplementation, xerostomia, and mucositis that may occur with treatment. A successful speech and swallowing outcome requires a high degree of patient motivation and cooperation.

As a rule, the more limited the surgical resection, the less likely a patient is to experience significant functional impact on speech and swallowing. Patients requiring wide surgical resections of the retromolar trigone or procedures that extend deep within the tongue base experience the most significant impact on swallowing. Floor of mouth resections are associated with a detrimental effect on chewing.¹³⁹ Radiation, alone or in combination with surgery, has a side effect profile including problems such as xerostomia, lymphedema, and fibrosis with scar contracture. Postoperatively, the speech and swallowing therapist will assess the patient’s ability to progress to normal oral intake. Prevention of aspiration pneumonia in these patients is vital. An early postoperative evaluation of swallowing function with a flexible laryngoscope (with a fiberoptic endoscopic evaluation of swallowing protocol) or modified barium swallow can guide the direction of swallowing rehabilitation.

Pain Management

Patients undergoing treatment of oral cavity malignancies, in particular those having extensive surgical procedures with reconstruction, require a comprehensive pain management plan. Initial postoperative pain management is accomplished by the use of patient-controlled analgesia (PCA). A transition from intravenous analgesia to oral administration is important as the patient progresses to discharge. A visual analog pain scale will aid the physician and patient in adjusting the amount of analgesia required. A balance must be struck between providing adequate pain control and excessive sedation, which delays ambulation and rehabilitation. The importance of physical therapy for patients recovering from extensive surgical and reconstructive procedures is significant. Finally, for patients whose pain management is difficult, consultation by the pain management service is helpful for tailoring the analgesia regimen.

Palliative Care

Palliative care options should be considered for patients with unresectable disease or when recurrence precludes curative therapy. Palliative chemotherapy and radiation can provide symptom relief when pain and tumor growth adversely affect quality of life. Decisions to place a tracheostomy and gastrostomy tube are individualized and may provide significant comfort without unnecessarily prolonging life. Hospice consultation is important for aiding the patient and family with making end-of-life decisions.

Follow-up

Follow-up occurs in two phases for patients undergoing surgery and radiation for oral malignancies. In the initial phase, when the patient is recovering from surgery or radiation therapy, weekly follow-up may be necessary to assess nutritional status and monitor rehabilitation goals. The second phase is cancer surveillance. See Table 96-4 for the American Head and Neck Society guidelines for cancer surveillance.¹⁴⁰

Table 96-4 American Head and Neck Society Guidelines for Cancer Surveillance

From Deschler DG, Hayden RE. The optimum method for reconstruction of complex lateral oromandibular-cutaneous defects. Head Neck. 2000;22:674-679.

In addition to monitoring for locoregional recurrence, an annual chest radiograph, liver function tests, and comprehensive head and neck examination are important for detecting metachronous lesions. A biannual thyroid-stimulating hormone (TSH) determination is necessary for patients after neck irradiation, as are frequent dental evaluations for dentate patients.

Long-term survival in the face of disease recurrence is limited. Argiris reported on the experience of 399 patients in Eastern Cooperative Oncology Group trials (ECOG 1393 and 1395) receiving palliative chemotherapy in the setting of locoregionally recurrent or metastatic disease. At 1 year, the overall survival was 32%. At 2 years, 49 patients (12%) were alive. Only 6 patients lived to 5 years after the diagnosis of recurrence.¹⁴¹

Complications

Postoperative complications are common after extensive head and neck surgical procedures. In the immediate postoperative period the patient is at greatest risk for pulmonary embolism, gastric ulceration, hemorrhage, delirium tremens, and aspiration pneumonia. Vigilance for symptoms indicative of these adverse events may permit early detection and life-saving interventions.

A late complication after radiation therapy is osteoradionecrosis. Early treatment may prevent substantial bone loss and includes hyperbaric oxygen therapy, antibiotics, and sequestrectomy. When mandibular loss occurs, microvascular reconstruction has been successful in salvaging the remaining healthy tissue while reconstructing the necrotic tissue lost.

Delayed pathologic fracture may occur after marginal mandibulectomy when inadequate mandible remains. After bony reconstruction, a nonunion may occur and lead to infection, mobility, or fistula formation.