Does asymptomatic primary tumor need to be removed in unresectable metastatic colon cancer?

Every third colorectal cancer patient has inoperable metastatic disease upon diagnosis. And quite often the primary tumor is asymptomatic. The question stands for surgeon and medical oncologist, whether to proceed with upfront surgery or systemic chemotherapy. Considering the absence of prospective randomized clinical trials, we must discuss all potential benefits and drawbacks of both approaches, biological interactions between the primary tumor and metastases, risk of complications, associated with primary tumor during chemotherapy, relative efficacy of chemotherapy for primary tumor and metastatic nodes, we must perform a retrospective analysis of prognostic value of primary tumor resection. This review discusses all of the aforementioned questions.