Combined analysis of imaging tumor capsule with imaging tumor size guides the width of resection margin for solitary hepatocellular carcinoma

Background:The optimal width of resection margin(RM)for hepatocellular carcinoma(HCC)remains controversial.This study aimed to investigate the value of imaging tumor capsule(ITC)and imaging tu-mor size(ITS)in guiding RM width for patients with HCC.Methods:Patients who underwent hepatectomy for HCC in our center were retrospectively reviewed.ITC(complete/incomplete)and ITS(≤3 cm/>3 cm)were assessed by preoperative magnetic resonance imaging(MRI).Using subgroup analyses based on ITC and ITS,the impact of RM width[narrow RM(<5 mm)/wide RM(≥5 mm)]on recurrence-free survival(RFS),overall survival(OS),and RM recurrence was analyzed.Results:A total of 247 patients with solitary HCC were included.ITC and ITS were independent predictors for RFS and OS in the entire cohort.In patients with ITS≤3 cm,neither ITC nor RM width showed a significant impact on prognosis,and the incidence of RM recurrence was comparable between the narrow RM and wide RM groups(15.6%vs.4.3%,P=0.337).In patients with ITS>3 cm and complete ITC,the narrow RM group exhibited comparable RFS,OS,and incidence of RM recurrence with the wide RM group(P=0.606,0.916,and 0.649,respectively).However,in patients with ITS>3 cm and incomplete ITC,the wide RM group showed better RFS and OS and a lower incidence of RM recurrence compared with the narrow RM group(P=0.037,0.018,and 0.046,respectively).Conclusions:As MRI-based preoperative markers,conjoint analysis of ITC with ITS aids in determining RM width for solitary HCC patients.Narrow RM is applicable in patients with ITS≤3 cm regardless of ITC status and in those with ITS>3 cm and complete ITC.Wide RM is preferred in those with ITS>3 cm and incomplete ITC.