31. MULTICENTER RANDOMIZED CLINICAL TRIAL OF CRT VS DCF AS INITIAL TREATMENT FOR SUBSEQUENT CONVERSION SURGERY FOR CLINICAL T4B ESOPHAGEAL CANCER

Abstract Backgroud Although induction followed by conversion surgery (CS) is potentially curative for T4b esophageal cancer, the optimal initial induction treatment is unclear. We conducted a multicenter randomized prospective phase 2 trial of chemoradiotherapy (CRT) versus chemotherapy (CT) as initial induction therapy for CS in clinical T4b esophageal cancer. We compared treatment effects, adverse events and survival. Methods Ninety-nine patients with T4b esophageal cancer were randomly allocated to chemoradiotherapy (Group A, n = 49) or CT (Group B, n = 50) as initial induction treatment. CRT consisted of radiation (50.4 Gy) with cisplatin and 5-fluorouracil. CT consisted of 2 cycles of docetaxel plus cisplatin and 5-fluorouracil (DCF). CRT or CT was followed by CS if resectable. If unresectable, the patient received the other treatment as secondary treatment. CS was performed if resectable after secondary treatment. The primary end point was 2-year overall survival. The Japan Registry of Clinical Trials (s051180164). Results In Group A, CS was performed in 34 (69%) and 7 patients (14%) after initial and secondary treatment. In Group B, CS was performed in 25 (50%) and 17 patients (34%) after initial and secondary treatment. The R0 resection rate after initial and secondary treatment was similar (78% vs 76%, P = 1.000). Adverse events including leukopenia, neutropenia, febrile neutropenia, and diarrhea were significantly more frequent in Group B. Group A had better histological complete response of the primary tumor (40% vs 17%, P = 0.028) and histological nodal status (P = 0.038). The 2-year survival rate was 55.1% (95% CI 41.1–68.3%) in the CRT group and 34.7% (95% CI 22.8–48.9%) in the CT group, although the difference was not significant (p = 0.11). Local and regional lymph node recurrence in patients undergoing R0 resection was significantly higher in CT group than CRT group (30% versus 8%, p = 0.03 and 37% versus 8%, p = 0.002, respectively). Conclusions The results of the present trial showed that upfront CRT was superior to upfront CT in terms of adverse effects, pathological effects and 2 year-overall survival as initial induction therapy for CS in clinical T4b esophageal cancer.