Impact of subcutaneous and visceral fat adiposity in patients with colorectal cancer

Abstract

Background: Although different body composition including fat adiposity has known to be associated with survival in patients with colorectal cancer (CRC), the clinical significance was inconsistent. We investigated prognostic impact of visceral and subcutaneous fat adiposity in patients with CRC after surgical resection.

Material and methods: This retrospective single center study included 987 stage I-III CRC patients (583 males, and 404 females) who underwent surgical resection between March 2005 and April 2014. Preoperative diagnostic computed tomography images were used to quantify visceral fat area (VFA) and subcutaneous fat area (SFA). The sex-specific optimal cut-off value for body fat composition was defined using the X-tile program. The Cox proportional hazards model was used to determine the correlation fat composition and disease-free survival (DFS). Harrell's concordance index (C-index) and integrated area under curve (iAUC) were used to evaluate the predictive ability of cut-derived stratification.

Results: In univariate analysis, high SFA (≥141.73 cm2 in males and ≥168.71 cm2 in females) and high VFA (≥174.38 cm2 in male and ≥83.65 cm2 in female) were identified as significant prognostic factors for better DFS (p = .001 and p = .003 respectively). However, multivariate analysis revealed that high SFA independently predicted longer DFS (HR 0.505; 95% CI 0.266-0.957; p = .036) whereas, high VFA did not (HR 0.656; 95% CI 0.402-1.071; p = .092). Combining stage and SFA-cutoff showed better discriminatory performance than the model using stage solitary with respect to C-index (0.667; 95% CI 0.623-6.711; p = .0098) and iAUC (0.601; 95% CI 0.556-0.620).

Conclusion: High SFA was correlated with better DFS in patients with CRC. Subcutaneous fat can have additive predictive capability when incorporated into clinical decision-making.