Do low skeletal muscle bulk and disturbed body fat mass impact tumor recurrence in stage I/II hepatocellular carcinoma undergoing surgery? An observational cohort study

INTRODUCTION: The influence of deranged body composition on stage I/II hepatocellular carcinoma (HCC) after surgery remains undetermined. The current study aimed to investigate the impact of low skeletal muscle bulk and disturbed body fat mass on the recurrence outcome of stage I/II HCC patients undergoing liver resection. The associated metabolomic alterations were also assessed. METHODS: From 2012 to 2021, stage I and II HCC patients who underwent liver resection at our institute were retrospectively reviewed. Their preoperative body composition including skeletal muscle mass and body fat volume was measured by computed tomography (CT). The recurrence outcome was recorded and analyzed. The preoperative serum was collected and subjected to metabolomic analysis. RESULTS: A total of 450 stage I and II HCC patients were included in the current study. Among them, 76% were male and around 60% had HBV infection. After stratified by normal cut-off values obtained from a healthy cohort, 6.4% of stage I/II HCC patients were found to have a low psoas muscle index (PMI), 17.8% a high subcutaneous adipose tissue (SAT) index, and 27.8% a high visceral adipose tissue (VAT) index. Cox regression multivariate analysis further demonstrated that low PMI and high SAT index were independent prognostic factors for time-to-recurrence (TTR) after surgery. Metabolomic analysis discovered that free fatty acid β-oxidation was enhanced in patients with low PMI or high SAT index. CONCLUSION: The current study demonstrated that reduced psoas muscle mass may impair while elevated SAT may prolong the TTR of stage I/II HCC patients undergoing liver resections. VAT, on the other hand, was not associated with recurrence outcomes after surgery. Further studies are warranted to validate our findings.