Bilobar versus unilobar multiple colorectal liver metastases: a propensity score analysis of surgical outcomes and recurrence patterns

Background Bilobar multiple colorectal liver metastases (MCLM) are often considered incurable or associated with a poor prognosis even after R0 resection. This study was designed to compare the long-term outcomes and recurrence patterns after one-stage resection in patients with bilobar versus unilobar MCLM. Methods The records of patients undergoing parenchymal-sparing intent hepatectomy between 1994 and 2015 were reviewed. Survival and recurrence patterns were analyzed by propensity score matching. Results The study population included 140 patients: 81 patients with bilobar MCLM versus 59 patients with unilobar MCLM. In the propensity score matching analysis (bilobar, n = 35 vs. unilobar, n = 35), the short-term outcomes did not differ between the two groups. Five-year overall survival (54.8% in bilobar vs. 51.2% in unilobar; P = 0.388) and recurrence-free survival (28.5% in bilobar vs. 36.2% in unilobar; P = 0.261) also did not differ. No significant differences were found in liver-only recurrence (22.9% in bilobar vs. 25.7% in unilobar; P = 1.000) and other recurrence patterns. Conclusions The clearance of bilobar MCLM by one-stage resection of parenchymal-sparing intent provided comparable long-term survival to unilobar MCLM.