Impact of tumor proximity to vessel on conversion in laparoscopic liver resection: A retrospective cohort study.

ABSTRACT

BACKGROUND: Although various difficulty scoring systems have been proposed for laparoscopic liver resection (LLR), details remain uncertain regarding distance between the tumor and vessels as a factor of difficulty. We aimed to examine the risk factors for conversion to open hepatectomy in LLR, including distance between tumor and vessels. METHODS: Between January 2012 and December 2022, 118 patients who underwent LLR were retrospectively enrolled and their perioperative characteristics were evaluated. RESULTS: A total of 10 cases (8.5%) were converted to open hepatectomy during LLR. The conversion group had lower platelet count, shorter distance between the tumor and a medium vessel (defined as diameter of 5-10 mm), and greater tumor depth compared with the pure LLR group. Receiver-operating characteristic curve analysis identified 10 mm as the optimal cutoff value of tumor proximity to a medium vessel (sensitivity, 80.0%, specificity, 78.7%, AUC 0.817) for predicting conversion. In multivariate analysis, lower platelet count (p = .028) and tumor proximity within 10 mm to a medium vessel (p = .001) were independent risk factors for conversion in LLR. CONCLUSIONS: Our study suggests tumor proximity within 10 mm to a medium vessel and lower platelet count as predictors of unfavorable intraoperative conversion in LLR.