Recent advances in chemotherapy and chemoradiotherapy for gastrointestinal tract cancers: adjuvant chemoradiotherapy for gastric cancer

Chemoradiotherapy (CRT) is one of the effective modalities for the local control of gastric cancer. Advances in CRT as an adjuvant treatment have been made in the West. The INT0116 trial demonstrated that postoperative chemotherapy with 5-fluorouracil (FU) plus leucovorin and concomitant 45-Gy radiation significantly improved the survival of gastric cancer patients who received gastrectomy with D0 or D1 lymph node dissection. As the result of this trial, the standard treatment for curable gastric cancer in the United States has been considered as a combination of surgery and postoperative CRT. The great interest in CRT in the adjuvant setting for gastric cancer has induced oncologists, particularly in the West, to conduct new clinical trials using various kinds of anticancer drugs. However, there is no rationale for adjuvant CRT after D2 dissection. Large-scale randomized controlled trials in Japanese patients have shown significant improvement of overall survival brought about by postoperative adjuvant chemotherapy with S-1. The results of these studies have suggested that even D2 surgery alone brings about much better survival for patients than limited surgery plus adjuvant CRT. Thus, strategies for the postoperative treatment of gastric cancers should be classified according to the degree of surgery.