Treatment of stage IV gastric cancer with induction chemotherapy using S-1 and cisplatin followed by curative resection in selected patients

BACKGROUND The standard treatment for stage IV gastric cancer is chemotherapy, but outcomes remain poor. The effectiveness of induction chemotherapy followed by surgery in selected patients who had a good response to chemotherapy is unclear. METHODS A total of 59 patients with stage IV gastric cancer received induction chemotherapy with S-1 and cisplatin. In each cycle, oral S-1 (80 mg/m2) was administered for 3 weeks, followed by a 2-week drug holiday. Intravenous cisplatin (60 mg/m2) was administered on day 8 after adequate premedication and hydration. If unresectable features resolved after chemotherapy, patients underwent curative (R0) resection. The safety and outcomes of this treatment combination were evaluated, and predictive factors for survival were determined. RESULTS Thirteen of 59 patients (22%) were eligible for R0 resection after induction chemotherapy. Kaplan-Meier analysis showed an overall median survival time of 13 months and a 3-year survival rate of 18.2%. Among patients who underwent R0 resection, the median survival time was 53 months and the 3-year survival rate was 53.8%. Multivariate analyses showed that negative para-aortic lymph nodes and undergoing R0 resection were independent predictors of survival. CONCLUSIONS Treatment of stage IV gastric cancer with S-1 and cisplatin induction chemotherapy followed by R0 resection is safe and may improve survival compared with chemotherapy alone. Further study of this dual-modality therapy is warranted.