The Liver Transection Area Is a Novel Predictor for Surgical Difficulty in Laparoscopic Liver Resection.

: A difficulty scoring system was developed to estimate the surgical outcomes of laparoscopic liver surgery (LLS); however, the effect of the liver transection area (LTA) on LLS outcomes have not been previously examined. Therefore, this study investigated the predictive significance of the LTA for LLS. : This retrospective study included 106 patients who underwent LLS in our hospital between January 2012 and December 2023. The association of the LTA with the surgical difficulty level and operative time was investigated. Multivariate analyses were performed to identify factors predicting surgical difficulty in LLS. : The median LTA and operative time were 62.5 (IQR, 36.0-91.8) cm and 250 (IQR, 195-310) minutes, respectively. The LTA was significantly associated with surgical difficulty as evaluated using the IWATE Criteria. Moreover, the LTA significantly correlated with operative time (r = 0.19, < 0.001). The multivariable analyses found that the LTA (≥59 cm) (odds ratio [OR], 6.07; 95% confidence interval [CI], 2.38-16.6; < 0.001) and the type of LLS (≥segmentectomy) (OR, 3.79; 95% CI, 1.35-11.4; = 0.01) were significant factors associated with surgical difficulty. : The LTA is a useful parameter that reflects the difficulty of LLS.