Synchronous colorectal liver metastases: the "surgeon as oncologist" perspective

Colon cancer presenting with synchronous metastatic disease to the liver creates challenging clinical scenarios. Traditionally, patients with resectable synchronous colorectal liver metastases (CRLM) were treated initially by resection of the primary tumor followed by an arbitrary but often prolonged duration of postoperative chemotherapy. In patients without progression of disease while receiving this postoperative chemotherapy, surgery for CRLM was then offered. In recent years this algorithm has been questioned, and in this review we describe the rationale for this classic approach as well as data that suggests that this model should be reconsidered. Evolving definitions of resectability of CRLM as well as technical advances in liver surgery have increased the number of patients eligible for potentially curative resections. There still exists controversies regarding the role of chemotherapy, its timing, the feasibility of simultaneous CRLM and primary tumor resection, and how to treat the asymptomatic primary in the context of CRLM. While it is a valuable treatment in unresectable CRLM, the role of prehepatectomy chemotherapy in resectable CRLM should be reconsidered as its survival benefits have not been well established and there are reports of chemotherapy related morbidity following hepatic resection. Although simultaneous primary tumor and CRLM resection has been traditionally viewed as prohibitively morbid, recent data suggests that it may be safe in carefully selected patients with limited volume of metastatic disease. The traditional paradigm of treating synchronous CRLM (SCRLM) should be reconsidered. Randomized controlled trials are necessary to help clarify the role and timing of chemotherapy in the treatment of SCRLM.