Rigid Bronchoscopic Intervention for Central Airway Obstruction and Concurrent Superior Vena Cava Syndrome Caused by Small Cell Carcinoma

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Chapter 28 Rigid Bronchoscopic Intervention for Central Airway Obstruction and Concurrent Superior Vena Cava Syndrome Caused by Small Cell Carcinoma

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This chapter emphasizes the following elements of the Four Box Approach: risk-benefit analyses and therapeutic alternatives; anesthesia and other perioperative care; and referrals to medical, surgical, or palliative/end-of-life subspecialty care.

Case Description

An 85-year-old male with an extensive history of smoking (70 pack-years) developed shortness of breath, which worsened within the week before admission. He had excessive cough, which resulted in hemoptysis (estimated at a few teaspoons/day). Review of systems revealed weight loss (20 kg/6 mo), as well as facial and neck edema for several months. Vital signs showed blood pressure of 150/70 mm Hg, heart rate of 115/min, body temperature of 37.2° C, and respiratory rate of 22/min. On physical examination, the patient had prominent edema of the face, neck, and bilateral upper extremities, with neck vein distention and multiple engorged dilated vessels over the anterior aspect of the chest. Expiratory wheezing was heard on the left hemithorax, and no breath sounds were heard on the right. The rest of the physical examination was normal. Laboratory findings showed WBC count of 19,700 (neutrophils 81.3%, lymphocytes 2%), hemoglobin of 12.8 g/dL, and platelet count of 310,000/mm3. Arterial blood gas analysis showed pH of 7.54, arterial carbon dioxide tension (PaCO2) of 39 mm Hg, and partial pressure of oxygen in arterial blood (PaO2) of 64 mm Hg (O2 = 2 L/min on nasal prong). Electrolytes were within normal limits. Electrocardiography (ECG) showed sinus tachycardia with bifascicular block. Two-dimensional echocardiography showed a small secundum-type atrial septal defect, normal left ventricular function, and no evidence of right ventricular dysfunction. Chest radiograph revealed near complete opacification of the right hemithorax (Figure 28-1). Chest computed tomography showed a 7.3 × 5.7 cm large mediastinal and right hilar mass with near complete occlusion of the superior vena cava (SVC); the mass had eroded into the right mainstem bronchus and lower trachea, causing near complete collapse of the right lung and a right pleural effusion (see Figure 28-1). Bronchoscopic biopsy and washings performed at an outside facility showed small cell carcinoma. The patient was placed on broad-spectrum antibiotics and was transferred to our hospital for consideration for bronchoscopic intervention to restore airway patency. On repeat bronchoscopic examination, the tumor involved the lower trachea above the main carina, completely occluding the entrance to the right main bronchus (see Figure 28-1). The patient was a retired clothing factory owner who lived with his wife. He had a very close family including several children who were actively involved in his care. His family wanted him to receive active and what was hoped would be effective treatment for this tumor. Emergency radiotherapy of first intention had not been recommended by a radiation oncologist because of concerns for worsening tracheal obstruction by radiation-induced edema and ongoing sepsis. Therefore urgent rigid bronchoscopy was scheduled to establish airway patency and to potentially avoid worsening sepsis and respiratory failure.

Case Resolution

Initial Evaluations

Physical Examination, Complementary Tests, and Functional Status Assessment

This patient had a new diagnosis of small cell lung cancer (SCLC). The Veterans Affairs Lung Study Group (VALSG)* staging system has been used traditionally to stage SCLC because of its simplicity. Based on this system, limited disease is seen in 30% to 40% at presentation, and extensive disease in 60% to 70% of patients. Accurate staging is clinically relevant because patients with limited-stage disease are treated with combined modality therapy, and those with extensive disease receive chemotherapy alone. Staging by the VALSG system is controversial in patients with locally advanced disease such as contralateral hilar or supraclavicular nodes, pericardial effusions, or malignant pleural effusions, as were seen in this case; for instance, this group is neither precisely defined (as limited or extended disease) nor uniformly managed by different investigators and is frequently excluded from protocols for limited-stage disease. In this regard, the consensus report from the International Association for the Study of Lung Cancer (IASLC) modified the VALSG classification based on the tumor-node-metastasis (TNM) staging system, and only patients with TxNxM1 were considered as having extended disease, so that IASLC criteria include more patients in the prognostically superior limited disease category than are assigned by the VALSG criteria.1 The TNM staging system used for non–small cell lung cancer (NSCLC) has been increasingly advocated by the IASLC to stage SCLC because it describes the extent of disease more accurately than the VALSG system. In fact, the new IASLC M1a descriptors (pleural effusion, pericardial effusion, and contralateral/bilateral intrapulmonary metastasis) adequately prognosticate SCLC patients as having metastatic disease. In fact, the IASLC recommends the use of TNM for all cases of SCLC.2

Similar to our case, patients with advanced-stage lung cancer of any type may present with a variety of loco-regional complications, including central airway obstruction (CAO), superior vena cava (SVC) syndrome, hemoptysis, and post obstructive pneumonia. Patients with CAO usually are not candidates for surgical resection for physiologic or oncologic reasons. Furthermore, chemotherapy and/or radiotherapy in the setting of post obstructive pneumonia may exacerbate the risk for sepsis. The prognosis is guarded, and in the presence of atelectasis, the ability of external beam radiation alone to restore airway patency was shown to be as low as 23%.3 SVC obstruction by lymph node metastasis into the right paratracheal or precarinal station or by direct invasion of lung cancer can cause SVC syndrome* in up to 10% of newly diagnosed cases of SCLC.4 Tumor growth in most cases is gradual, allowing sufficient time for collateral circulation to develop, but many patients eventually present with headache, swelling of the face and neck, and even coma. However, SVC syndrome is no longer considered an emergency, and the use of intravascular stents is recommended only for relapsed or persistent SVC obstruction following chemotherapy or radiation therapy in SCLC.5

Comorbidities

SCLC is the most common malignancy associated with neurologic paraneoplastic syndromes produced by autoantibodies that cross-react with both SCLC cells and the central nervous system or the neuromuscular junction. These antibodies can cause the Lambert-Eaton myasthenic syndrome (LEMS) in 3% of patients suffering from SCLC.6 Our patient had no obvious neurologic symptoms suggesting LEMS or other paraneoplastic neurologic syndromes seen in SCLC such as limbic encephalitis, paraneoplastic cerebellar degeneration, autonomic neuropathy, or subacute peripheral sensory neuropathy. SCLC cells can also produce a number of polypeptide hormones, including adrenocorticotropic hormone (ACTH) and antidiuretic hormone, resulting in the syndrome of inappropriate antidiuretic hormone and Cushing’s syndrome, respectively. Our patient had no symptoms or laboratory markers suggesting these diagnoses, all of which could affect anesthesia and procedural planning.

Support System

Cancer treatment is emotionally and physically exhausting for patients, so it is important for them to have a good support system during this critical time of their lives. This patient had many family members who were eager to help. Strong family support and faith are noted to have a positive effect on response to cancer treatment.7 If patients, friends, or family members have difficulty coping with the emotional aspects of the illness, experienced professionals in mental health services, social work services, and pastoral services, and local support groups can assist.8

Procedural Strategies

Expected Results

This patient had complete obstruction of the right main bronchus and severe (70%) obstruction in the distal trachea. Palliating CAO was expected to improve dyspnea, lung function, and quality of life.9,12,13 In patients with inoperable or recurrent NSCLC or SCLC occluding a central airway, studies showed no difference in overall survival between those who received both neodymium-doped yttrium aluminum garnet (Nd:YAG) laser treatment and radiation therapy (mean external dose, 53.1 Gy) as compared with historical controls treated with radiation therapy alone. In patients with restored airway lumen, however, the time interval from treatment to death was prolonged by 4 months compared with those for whom a fully patent airway could not be restored.14 Successful restoration of patency of a major airway occluded by intraluminal tumor using laser resection reduces the likelihood of respiratory failure as a cause of death and does not affect the likelihood of massive fatal hemorrhage, which was a major cause of death in these patients with or without laser treatment.14 Therefore a major issue in these patients is whether they and their families should be warned of the possibility of major bleeding and informed of measures to take should this unfortunate event occur outside the hospital setting.*

Risk-Benefit Analysis

Because the goal of the procedure is palliation, treatment should have the least possible risk of side effects and discomfort. The risks of intervention warrant careful consideration when patients have significant comorbidities such as a large mediastinal mass, SVC syndrome, or very advanced age.16,17 In our patient, the risks of further physiologic compromise, massive bleeding, and hemodynamic instability were considered to be outweighed by the potential benefit of restoring airway patency to improve functional status and offer systemic therapy. Therapeutic strategies should be elaborated on a case-by-case basis, and advantages and disadvantages of various alternatives discussed with the patient and family if desired, before or during the informed consent process.

Therapeutic Alternatives for Restoring Airway Patency

1. Emergent external beam radiation therapy (EBRT) could have been used for palliating the airway obstruction and the SVC syndrome.18 Initiation of EBRT as primary treatment without attempts at restoration of airway patency in this patient in our opinion would have been of doubtful benefit. EBRT is only variably effective for cancer-induced CAO when the obstruction is severe enough to cause atelectasis, as occurred in our patient. In a study of 330 patients, EBRT palliated hemoptysis in 84% of patients and SVC syndrome in 86% of patients, but atelectasis in only 23%.3 However, EBRT following effective laser treatment could potentially improve survival.19 EBRT had not been recommended as the primary treatment in our patient because of concerns for worsening tracheal obstruction by radiation-induced edema and because of ongoing sepsis in the setting of post obstructive pneumonia. It is noteworthy, from a systemic therapy perspective, that a meta-analysis showed no obvious benefit for combined chemotherapy and radiation therapy over chemotherapy alone in limited-stage SCLC patients older than 70 years. However, more recent trials have revealed a clear-cut benefit for physically “fit elderly”* patients to receive combined modality therapy versus chemotherapy alone, although outcome generally remains inferior to that of younger patients.20

2. Chemotherapy for SCLC involves cisplatin-etoposide regimens and in general is combined with chest radiotherapy for limited disease.21 A systematic review of 29 trials involving 5530 patients found that platinum-based chemotherapy regimens did not offer a statistically significant survival benefit or overall tumor response compared with non–platinum-based regimens. However, platinum-based chemotherapy regimens did increase complete response rates at the cost of more frequent adverse events, including nausea and vomiting, anemia, and thrombocytopenia.22 CAO is present in as many as 20% to 30% of patients with lung cancer. These patients may develop post obstructive pneumonia.23 Acute infection, as was seen in our patient, is a contraindication to administration of chemotherapy and is an exclusion criterion in most clinical trials.24 We therefore decided to initially proceed with bronchoscopic restoration of airway patency with the patient under general anesthesia.

Techniques and Results

Anesthesia and Perioperative Care

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