A Preoperatively Predictive Difficulty Scoring System For Laparoscopic Hepatectomy Of Primary Liver Cancer

Objectives The aim of this study was to evaluate the risk factors that influence the the difficulty of laparoscopic hepatectomy for primary liver cancer and to establish an objective and effective scoring system to predict the surgical difficulty preoperatively.Methods This study included patients with primary liver cancer undergoing laparoscopic hepatectomy from December 2012 to December 2017.Univariate and multivariate analysis were performed to determine the independent predictors for surgical difficulty based on the operation time during laparoscopic hepatectomy.A logistic regression model was used to developed a predictive difficulty scoring system based on the coefficients.Results Univariate analysis showed that there were significant differences in gender,maximum diameter of tumor,BMI,tumor location,extent of resection,tumor depth,tumor number,AFP level and hemoglobin concentration between short-term and long-term groups.Multivariate analysis showed that the maximum diameter of tumor,BMI,tumor location and extent of resection were independent predictors for surgical difficulty.The maximum diameter of tumor > 35.5mm,BMI > 25kg/m2,tumor located in posterosuperior segments,resection except wedge resection and left laterlar sectionectomy were significantly correlated with the prolongation of operation time.After simplifying the coefficients of logistic binary regression equation,the maximum diameter of tumor,BMI,tumor location,the extent of resection were assigned respectively.All cases were graded according to the scoring system,with score of 0,1,1.5,2.5,3,4,and > 4.5 points.According to the relative risk between groups,the patients were divided into low-difficulty group(total score 0-1.5 points),medium-difficulty group(total score 2.5-4 points)and high-difficulty group(total score 4.5 points or more).Logistic regression model and simplified version of the scoring system model had the same AUC of 0.806.The operation time and intraoperative blood loss increased significantly with a stepwise increase of groups from low difficulty group to high difficulty group(P < 0.001).Conclusions An objective and effective scoring system was established to predict the difficulty of laparoscopic hepatectomy for primary liver cancer based on four independent risk factors,including the maximum diameter of tumor,BMI,tumor location and extent of resection.The score could reflect the difficulty of the surgery.