Gastroesophageal junction adenocarcinoma.

Abstract

The incidence rate of adenocarcinoma of the esophagogastric junction (AEG) is increasing in association with the epidemiologic rise in distal esophageal adenocarcinoma and gastric cardial (AEG type III) tumors. The overall survival rate is poor in most patients with AEG because lymph node or visceral metastases are frequently present at the time patients become symptomatic. A few patients are identified early in the disease because of screening for gastroesophageal reflux and Barrett's esophagus. Early stage AEG (T1N0 or T2NO, carcinoma in situ, or severe dysplasia ) can in many instances be cured with surgery alone. Ablative treatments for early stage AEG, including endoscopic fulguration by cautery and laser or photodynamic therapy, are investigational at this time. Locoregionally advanced AEG (T3, T4, N1, or M1a ) without distant systemic metastases (M1b) has a poor overall survival rate with surgery alone or definitive chemotherapy and radiation therapy without surgery. Analysis of the use of multimodality treatment strategies for locoregionally advanced AEG types I and II have demonstrated improved survival rates in two small phase III trials with preoperative concurrent chemoradiotherapy followed by surgical resection. In contrast, three small phase III trials with preoperative concurrent or sequential chemoradiotherapy in patients with predominantly squamous cell carcinoma did not demonstrate any clear survival advantage. Additionally, a randomized phase III study evaluating preoperative chemotherapy without radiation therapy in esophageal cancer (predominantly adenocarcinoma) has demonstrated no survival benefit. In light of these results, additional large randomized phase III studies are needed to confirm the potential benefit of preoperative concurrent chemoradiotherapy. At the present time, preoperative chemoradiotherapy remains investigational. For locoregionally advanced gastric adenocarcinoma, including AEG type III, postoperative concurrent 5-fluorouracil (5-FU)-based chemoradiotherapy is associated with improved survival as demonstrated in a recently completed random assignment trial (INT 0116). As a result, surgery with postoperative chemoradiotherapy has recently become the standard of care for patients with AJCC stage II and III gastric adenocarcinoma (including patients with AEG type III). Metastatic AEG (M1b) should be treated with palliative chemotherapy (in good performance patients) or supportive care (poor performance) in asymptomatic patients. Radiation therapy and endoscopic stent placement (expandable wire mesh) can be used to palliate dysphagia in patients with M1b disease. The development of expandable stents and improved radiotherapy has obviated surgical bypass to palliate patients with symptomatic, metastatic AEG.