The goal of this study was to test the effect of HIPEC (Hyperthermic Intraperitoneal Chemotherapy) on survival and postoperative outcomes after complete cytroreductive surgery compared with resection alone. At 3 years, HIPEC significantly improved overall survival with almost 26% of patients alive at 3 years compared with 13% of patients in the surgery alone group. The median overall survival was 18.8 months for patients treated with HIPEC compared to 12.1 months for surgery alone. Survival results at 5 years were consistent. About 20% of patients were still alive at 5 years, and 15% of patients were considered cured by HIPEC. In conclusion, cytoreductive surgery plus HIPEC improved overall survival compared with resection alone for patients with gastric cancer with peritoneal carcinomatosis.