Associations of CT-Derived Body Composition with Textbook Outcomes and Early Death After Hepatectomy for Hepatocellular Carcinoma

Background: The aim of this study was to explore associations between CT-derived body composition parameters and textbook outcomes (TOs) and early death (within one year) after hepatectomy for hepatocellular carcinoma (HCC). Methods: Multiple CT-derived body composition parameters were evaluated in an exploratory analysis. Sex-specific, cohort-derived cutoff values were determined using receiver operating characteristic curve analyses. Logistic and Cox regression models were used to examine associations with failure to achieve TOs and survival outcomes, respectively. No individual body composition parameter was prespecified as the primary exposure or prioritized a priori for comparative analysis. Results: A total of 815 patients were included in our study. The multivariate logistic regression model revealed that a low psoas muscle index (PMI, cutoff values: 7.81 cm2/m2 in males and 3.84 cm2/m2 in females) and a high subcutaneous fat index (SFI, cutoff values: 56.75 cm2/m2 in males and 80.09 cm2/m2 in females) were independently associated with failure to achieve TOs. Patients were further divided into three groups: no risk factor (N = 231), one risk factor (N = 516), and two risk factors (N = 68). As the number of body composition risk factors increased, the incidence of non-TOs showed a significant increasing trend (p for trend <0.001), and the number of body composition risk factors remained independently associated with non-TOs (1 risk factor, OR: 1.99, 95% CI: 1.33–2.97, p < 0.001; 2 risk factors, OR: 3.54, 95%CI: 1.91–6.58, p < 0.001). The 1-, 3-, and 5-year rates were 95.0%, 83.1%, and 74.1% in patients with no risk factor, 88.5%, 77.1%, and 67.5% in patients with one risk factor, and 85.3%, 70.6%, and 61.8% in patients with two risk factors, respectively. Patients with different numbers of body composition risk factors showed significant differences in survival for early death (p = 0.009), whereas no statistically significant difference was observed for late death (p = 0.627). In the multivariate Cox analysis, the number of body composition risk factors remained independently associated with early death (1 risk factor, HR: 2.02, 95% CI: 1.05–3.87, p = 0.035; 2 risk factors, HR: 3.32, 95% CI: 1.36–8.06, p = 0.008). Conclusions: Our findings demonstrate that low PMI and high SFI were associated with failure to achieve TOs after hepatectomy for HCC. An increasing number of these two body composition factors showed graded associations with both non-TOs and early mortality, but not with late mortality. These findings warrant validation in independent cohorts.