A randomized, controlled, multicenter study comparing intensity-modulated radiotherapy plus concurrent chemotherapy with chemotherapy alone in gastric cancer patients with D2 resection.

Background And Purpose: The role of postoperative chemoradiotherapy in the treatment of patients with gastric cancer with D2 lymph node curative dissection is not well established. In this study, we compared postoperative intensity-modulated radiotherapy plus chemotherapy (IMRT-C) with chemotherapy-only in this patient population.

Materials And Methods: We randomly assigned patients with D2 lymph node dissection in gastric cancer to IMRT-C or chemotherapy-only groups. The adjuvant IMRT-C consisted of 400 mg of fluorouracil per square meter of body-surface area per day plus 20mg of leucovorin per square meter of body-surface area per day for 5 days, followed by 45 Gy of IMRT for 5 weeks, with fluorouracil and leucovorin on the first 4 and the last 3 days of radiotherapy. Two 5-day cycles of fluorouracil and leucovorin were given 4 weeks after the completion of IMRT. Chemotherapy-only group was given the same chemotherapy regimens as IMRT-C group.

Results: The median overall survival (OS) in the chemotherapy-only group was 48 months, as compared with 58 months in the IMRT-C group; the hazard ratio for death was 1.24 (95% confidence interval, 0.94-1.65; P=0.122). IMRT-C was associated with increases in the median duration of recurrence-free survival (RFS) (36 months vs. 50 months), the hazard ratio for recurrence was 1.35 (95% confidence interval, 1.03-1.78; P=0.029). COX multivariate regression analysis showed that lymph node metastasis and TNM stage were both the independent prognostic factors. Rates of all grade adverse events were similar in the two treatment groups.

Conclusions: IMRT-C improved RFS, but did not significantly improve OS among patients with D2 lymph node dissection in gastric cancer. Using IMRT plus chemotherapy was feasible and well tolerated in patients with gastric cancer after D2 resection.