Influence of primary tumor resection on survival in asymptomatic patients with incurable stage IV colorectal cancer

The influence of resection of the primary lesion on the prognosis of patients with incurable stage IV colorectal cancer is unclear. We retrospectively analyzed 158 asymptomatic patients with incurable stage IV colorectal cancer who received systemic chemotherapy in our center from 2002 to 2009, either without (chemotherapy group; n = 112) or after (resection group; n = 46) primary tumor resection. Primary tumor resection was performed if the fiberscope did not pass through the primary lesion. Survival was compared between the 2 groups, and the actual surgical intervention was assessed. At a median follow-up period of 26 months (range 7-91 months), the median survival times were 19.9 months in the resection group and 19.0 months in the chemotherapy group (HR = 0.81, 95 % CI 0.53-1.19, p = 0.29). Among the tumor resection group, 8 (17 %) experienced postoperative complications, with all showing improvement after conservative treatment. In the chemotherapy group, 18 patients (21 %) required surgical interventions for symptoms associated with progression of the primary tumor. Resection of the primary tumor in asymptomatic patients with incurable stage IV colorectal cancer was safe, but had no effect on prognosis.