Role of post-operative chemoradiation in resected gastric cancer

The curative management of gastric adenocarcinoma depends upon complete resection of the primary tumor. In patients with lymph node metastases in the resected specimen, the relapse and death rates from recurrent cancer are at least 70%-80%. There is continued debate over whether more extensive lymph node dissection (D2) improves survival when compared to less extensive operations. Until recently, attempts at preventing recurrence have employed adjuvant chemotherapy and have been ineffective. A large U.S. Intergroup study (INT-01 16) demonstrated that combined chemoradiation following complete gastric resection improves median time to relapse (30 vs. 19 months, P<0.0001) and overall survival (35 vs. 28 months, P = 0.01). The improvements in disease-free and overall survival resulting from postoperative chemoradiation have defined a new standard of care. An update of the results of INT-01 16 analysis performed in 2004 with 7 years median follow-up, not only confirms the benefits from post-operative chemoradiation but also shows that chemoradiation does not produce significant long-term toxicity. The recent publication of the first large adequately powered III neoadjuvant chemotherapy trial suggested this technique might downstage tumors and increase resectability. Future advances in the therapy of resectable gastric cancer may come from studies of pre-operative neoadjuvant chemoradiation and the application of targeted therapies such as growth receptor antagonists and anti angiogenesis agents.