Efficacy of neoadjuvant chemotherapy for initially resectable colorectal liver metastases: A retrospective cohort study

BACKGROUND The liver is the most common metastatic site of colorectal cancer. Hepatectomy is the mainstay of treatment for patients with colorectal liver metastases (CRLMs). However, there are cases of early recurrence after upfront hepatectomy alone. In selected high-risk patients, neoadjuvant chemotherapy (NAC) may improve longterm survival. AIM To determine the efficacy of NAC for initially resectable CRLMs. METHODS Among 644 patients who underwent their first hepatectomy for CRLMs at our institution, 297 resectable cases were stratified into an upfront hepatectomy group (238 patients) and a NAC group (59 patients). Poor prognostic factors for upfront hepatectomy were identified using multivariate logistic regression analysis. Propensity score matching was used to compare clinical outcomes between the upfront hepatectomy and NAC groups, according to the number of poor prognostic factors. Survival curves were estimated using the Kaplan-Meier method and compared using the log-rank test. RESULTS Preoperative carcinoembryonic antigen levels (>= 10 ng/mL) ( P = 0.003), primary histological type (other than well/ moderately differentiated) (P = 0.04), and primary lymph node metastases (>= 1) (P = 0.04) were identified as independent poor prognostic factors for overall survival (OS) in the upfront hepatectomy group. High-risk status was defined as the presence of two or more risk factors. After propensity score matching, 50 patients were matched in each group. Among high-risk patients, the 5-year OS rate was significantly higher in the NAC group (13 patients) than in the upfront hepatectomy group (18 patients) (100% vs 34%; P = 0.02). CONCLUSION NAC may improve the prognosis of high-risk patients with resectable CRLMs who have two or more risk factors.