Phase II trial of induction irinotecan-cisplatin followed by concurrent irinotecan-cisplatin and radiotherapy for unresectable, locally advanced gastric and oesophageal-gastric junction adenocarcinoma

Purpose: The prognosis of patients with unresectable M0 gastric cancer remains very poor. We performed a phase II trial to explore the efficacy and toxicity of induction irinotecan-cisplatin (IC) followed by concurrent irinotecan-cisplatin and radiotherapy (IC/RT) in this setting. Methods and materials: Patients with unresectable M0 gastric (GC) or oesophageal-gastric junction (EGJC) adenocarcinomas were treated with two courses of IC (irinotecan, 65 mg/m²; cisplatin, 30 mg/m² on days 1 and 8 every 21 days) followed by IC/RT (daily radiotherapy-45 Gy-with concurrent IC: irinotecan, 65 mg/m², and cisplatin, 30 mg/m², on days 1, 8, 15, and 22). Resectability was reassessed after this treatment, and surgical resection was performed if feasible. The primary endpoint was the R0 resection rate after induction treatment. Results: Seventeen patients were included in the study (EGJC: 6; GC: 11). An R0 resection was achieved in only 5 patients (29%), and according to the design of the trial (Simon's optimal two-stage) accrual of patients was terminated after the first stage. No patient died during IC, whereas 3 patients (24%) died during IC/RT and one of 5 resected patients (20%) died during the first 30 days after resection. The median survival was 10.5 months, and the actuarial 2-year survival rate was 27%. Conclusions: Induction IC followed by IC/RT showed poor efficacy and significant toxicity in patients with unresectable GC/EGJC.