Rationale for neoadjuvant chemotherapy of resectable colorectal cancer liver metastases: When is it useful?

Colorectal cancer is the third most common cancer and the third leading cause of cancer death in the United States (1). Moreover, approximately 20% of patients are diagnosed with synchronous colorectal liver metastases (CRLMs)(2). For patients with CRLM, the 5-year survival rate with after chemotherapy alone is approximately 11 percent (3). However, the 5-year and 10-year survival rates after surgical resection are reported as 38% and 26%, respectively (4). Therefore, surgery is considered a potentially curative intervention in CRLM. Unfortunately, not all CRLM patients are candidate for liver resection due to several factors.These include medical comorbidities and anatomical factors such as the number of metastases, tumor size and margin. In some cases, chemotherapy for unresectable tumors could convert the tumors to resectable. In other cases, neoadjuvant chemotherapy can help patients with synchronous metastatic disease undergo performed staged resection. Although neoadjuvant chemotherapy could be useful, its implementation is not yet standard and its use in resectable CRLM remains controversial. This review article focuses on the potential utility of neoadjuvant therapy for CRLMs.