CHAPTER 6 Esophagectomy
INDICATIONS FOR RESECTION
I. Esophageal Malignancies
A. The overwhelming majority of esophageal resections are performed for the treatment of carcinoma or premalignant lesions. The incidence of esophageal cancer varies greatly with geography; incidences are particularly high in China and South Africa. Esophageal carcinoma in the United States occurs more frequently in African Americans than in whites. The incidence of adenocarcinoma, however, has been rapidly increasing among middle-aged white men; it has now surpassed squamous cell cancer as the most prevalent histologic subtype of esophageal cancer in the United States. Alcohol and cigarette use are risk factors for both histologic subtypes. Approximately 15% of esophageal cancers occur in the upper one third, with the remainder occurring in the middle and lower thirds of the esophagus.
B. Staging of primary esophageal tumors is usually best achieved with the combination of CT, endoscopic ultrasound (EUS), and PET. CT is used to assess tumor invasion of local structures and identify distant metastatic disease. EUS (which can be combined with fine-needle aspiration) and PET are used to assess the regional lymph nodes. PET is probably the most sensitive modality for identifying distant metastases as well, assuming that the primary tumor is fluorine-18 fluorodeoxyglucose (FDG) avid. Carcinoma of the esophagus can spread widely. If a suspicious subcutaneous mass is found, biopsy should be performed. Neurologic symptoms should be evaluated using magnetic resonance imaging examination of the brain, and bone symptoms should be evaluated by bone scan.
C. The primary modalities for the treatment of esophageal cancers are surgery and chemoradiation therapy. Low survival rates with single-modality therapy, however, have prompted fairly uniform application of multimodality therapy, often consisting of neoadjuvant chemoradiation therapy and surgical resection of residual local disease. Surgery (either alone for very early disease or in combination with chemoradiation therapy for more advanced disease) provides potentially curative therapy. Importantly, surgical therapy may also provide significant palliation for dysphagia and local disease control so that oral intake may be maintained, even in patients who ultimately succumb to metastatic disease. In patients with clearly unresectable disease, palliative therapy without surgery should be the goal of treatment (Fig. 6-1).
II. Other Indications
A. Barrett’s esophagus describes the replacement of the esophageal squamous epithelium with sheets of columnar cells. The presence of Barrett’s esophagus is associated with severe gastroesophageal reflux disease and incompetence of the lower sphincter, which allows for prolonged exposure of the esophageal mucosa to acid. Barrett’s epithelium requires regular endoscopic surveillance with biopsies because it represents the first step toward dysplasia, a precursor to adenocarcinoma of the esophagus. Once Barrett’s epithelium has developed, the symptoms of heartburn may be somewhat ameliorated because the columnar epithelium is less sensitive to acid reflux. Close endoscopic surveillance is still required, however, even if symptoms have resolved or an antireflux procedure has been undertaken because neither of these guarantees subsistence of reflux or the return to normal mucosa. The presence of high-grade dysplasia or carcinoma on surveillance biopsy is an indication for esophageal resection. More recently, endoscopic therapies for dysplasia, Barrett’s epithelium, and early focal esophageal carcinoma have been explored. In skilled hands, these may displace resection for the treatment of early cases; however, long-term outcomes after such approaches have yet to be determined.
B. Caustic injury of the esophagus does not usually require immediate resection except in the rare case in which perforation occurs. Caustic burns, however, may result in stricture formation and contribute to the development of carcinoma; these may ultimately require esophagectomy for management.
C. Esophageal perforation is most commonly spontaneous (Boerhaave’s syndrome) or a complication of instrumentation (e.g., endoscopy). Esophageal perforation represents a surgical emergency; if untreated, severe mediastinitis may ensue. Surgical options include primary repair with drainage and esophagectomy.
D. Collagen vascular disorders, such as scleroderma, may result in significant esophageal atony, reflux esophagitis, and stricture formation. Patients with late-stage disease may require esophagectomy.
E. Achalasia is a functional disorder of the esophagus involving the destruction of Auerbach’s intermyenteric plexus. Patients typically have dysphagia that progresses over years. The esophageal dysfunction of achalasia is characterized by lack of coordinated peristalsis as well as nonrelaxation of the lower esophageal sphincter. These, in turn, lead to stasis and progressive esophageal dilation. Treatment may consist of endoscopic dilation of the lower esophageal sphincter or surgical esophagomyotomy. Because the stasis of achalasia favors the development of squamous cell carcinoma, long-term endoscopic surveillance is required, even after successful treatment. The persistent risk of carcinoma despite these therapies probably reflects imperfect relief of obstruction. In the absence of esophageal cancer, esophagectomy may be considered in patients with symptomatic megaesophagus or after failure of esophagomyotomy.
