Randomized Phase II Trial Evaluating Two Paclitaxel and Cisplatin–Containing Chemoradiation Regimens As Adjuvant Therapy in Resected Gastric Cancer (RTOG-0114)

Abstract

Purpose The investigational arm of INT0116, a fluorouracil (FU) and leucovorin–containing chemoradiotherapy regimen, is a standard treatment for patients with resected gastric cancer with a 2-year disease-free survival rate (DFS) of 52%. Toxicity is also significant. More beneficial and safer regimens are needed. Patients and Methods We performed a randomized phase II study among 39 cancer centers to evaluate two paclitaxel and cisplatin–containing regimens, one with FU (PCF) and the other without (PC) in patients with resected gastric cancer. Patients received two cycles of postoperative chemotherapy followed by 45 Gy of radiation with either concurrent FU and paclitaxel or paclitaxel and cisplatin. The primary objective was to show an improvement in 2-year DFS to 67% as compared with INT 0116. Results From May 2001 to February 2004 (study closure), 78 patients entered this study, and 73 were evaluable. At the planned interim analysis of 22 patients on PCF, grade 3 or higher GI toxicity was 59%. This was significantly worse than INT0116, and this arm was closed. Accrual continued on PC. The median DFS was 14.6 months for PCF and has not been reached for PC. For PC the 2-year DFS is 52% (95% CI, 36% to 68%). Conclusion Though PC appears to be safe and the median DFS favorable, the DFS failed to exceed the lower bound of 52.9% for the targeted 67% DFS at 2 years and can not be recommended as the adjuvant arm for future randomized trials.