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

Background: The influence of resection of the primary lesion on the prognosis of patients with incurable stage IV colorectal cancer is unclear.
Methods: 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.
Results: 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.
Conclusions: Resection of the primary tumor in asymptomatic patients with incurable stage IV colorectal cancer was safe, but had no effect on prognosis.