Comparison of Perioperative Chemotherapy versus Postoperative Chemoradiotherapy for Operable Stomach Cancer: A Western Canadian Province Experience.

Background: The standard approaches for resectable stomach cancer are postoperative chemoradiotherapy (PCR) or perioperative chemotherapy (PC). Limited evidence is available regarding the superiority of one of the two approaches. We aimed to compare the survival of patients with operable stomach cancer who were treated with PC or PCR. Methods: In this retrospective cohort study, patients with operable stomach cancer diagnosed between 2005–2015 in the province of Saskatchewan were identified and, based on type of treatment, were placed into PCR and PC groups. A Cox proportional multivariate analysis was performed to assess independent prognostic variables, including survival advantage of PC over PCR. Results: A total of 88 eligible patients with a median age of 66 (56–71) and a male to female ratio of 1:0.44 were identified. Seventy-three (83%) patients had pathologically node positive disease. Sixty-seven (76%) patients received PCR, while 21 (24%) patients received PC. The median overall survival of the whole group was 34 months, with 38 months (95% CI 24.6–51.3) in the PCR group vs. 30 months (14.3–45.7) in the PC group (p = 0.29). Median relapse-free survival was 34 months (20.7–47.3) in the PCR group vs. 23 months (6.7–39.3) in the PC group (p = 0.20). Toxicities were comparable. On multivariate analysis, T ≥ 3 tumor (HR, 3.57 (1.39–8.56)), neutrophil to lymphocyte ratio (LNR) > 2.8 (HR, 1.85 (1.05–3.25)), and positive resection margins (HR, 1.89 (1.06–3.37)) were independently correlated with inferior survival. Conclusions: This well-designed population based cohort study suggests a lack of survival benefit of PC over PCR. Both treatment options remain viable approaches for resectable stomach cancer.