Primary tumor resection before systemic therapy in patients with newly diagnosed colon cancer and unresectable metastases: pooled analysis

Chemotherapy is the primary treatment in patients with stage IV colon cancer and unresectable metastases. The prognostic value of primary tumor resection (PTR) before chemotherapy is not clear. Pooled analysis of the SYNCHRONOUS and CCRe-IV trials evaluated the prognostic value of PTR before systemic chemotherapy in patients with newly diagnosed stage IV colon cancer with synchronous unresectable metastases. A total of 393 patients at 100 centers in Austria, Germany, and Spain were randomly assigned to undergo PTR (n=187) or no PTR (n=206). Chemotherapy was not adminstered to 6.4% in the No PTR group and 24.2% in the PTR group. The median overall survival was 16.7 months (95% CI 13.2-19.2) in the PTR group and 18.6 months (16.2-22.3) in the No PTR group (p=0.191). There were no patient subgroups with overall survival benefit from PTR. Serious adverse events were more frequent in the No PTR group (10.2% versus 18.0%; p=0.027). The authors conclude that among patients with colon cancer and synchronous unresectable metastases, PTR before systemic chemotherapy was not associated with prolonged overall survival.