Neoadjuvant chemotherapy for colorectal liver metastases: A contemporary review of the literature

Abstract

Colorectal carcinoma (CRC) is one of the leading causes of cancer-related deaths worldwide, and up to 50% of patients with CRC develop colorectal liver metastases (CRLM). For these patients, surgical resection remains the only opportunity for cure and long-term survival. Over the past few decades, outcomes of patients with metastatic CRC have improved significantly due to advances in systemic therapy, as well as improvements in operative technique and perioperative care. Chemotherapy in the modern era of oxaliplatin- and irinotecan-containing regimens has been augmented by the introduction of targeted biologics and immunotherapeutic agents. The increasing efficacy of contemporary systemic therapies has led to an expansion in the proportion of patients eligible for curative-intent surgery. Consequently, the use of neoadjuvant strategies is becoming progressively more established. For patients with CRLM, the primary advantage of neoadjuvant chemotherapy (NCT) is the potential to down-stage metastatic disease in order to facilitate hepatic resection. On the other hand, the routine use of NCT for patients with resectable metastases remains controversial, especially given the potential risk of inducing chemotherapy-associated liver injury prior to hepatectomy. Current guidelines recommend upfront surgery in patients with initially resectable disease and low operative risk, reserving NCT for patients with borderline resectable or unresectable disease and high operative risk. Patients undergoing NCT require close monitoring for tumor response and conversion of CRLM to resectability. In light of the growing number of treatment options available to patients with metastatic CRC, it is generally agreed that these patients are best served at tertiary centers with an expert multidisciplinary team.

Keywords: Colorectal liver metastases; Neoadjuvant chemotherapy; Hepatic resection; Conversion therapy; Chemotherapy-associated liver injury; Disappearing liver metastases; Future liver remnant; Immunotherapy

Core Tip: Colorectal carcinoma is one of the leading causes of cancer-related deaths worldwide. Neoadjuvant chemotherapy is an important treatment strategy for patients with colorectal liver metastases that can downstage tumors and facilitate hepatic resection. Although its use in patients with initially resectable disease is controversial, it is currently recommended for those with unresectable to borderline resectable metastases.