Nomogram predicting short- and long-term outcomes in colon cancer based on CT body composition.

[BACKGROUND] We investigated the relationship between sarcopenia (low skeletal muscle index, SMI) and myosteatosis (high intermuscular adipose tissue, IMAT) accompanied by post-surgical adverse events and recurrence-free survival (RFS) in patients with colon cancer (CC) undergoing radical resection.

[METHODS] This retrospective study included 475 patients from the Affiliated Hospital of Qingdao University (original cohort) and 209 patients from Weihai Central Hospital Affiliated to Qingdao University (validation cohort) with CC who underwent radical surgical resection. Cox proportional hazards and logistic regression models were used to analyze the correlation between body composition and postoperative complications, as well as RFS. A nomogram was developed based on independent predictors of RFS, and its performance was evaluated.

[RESULT] The original cohort comprised 475 patients (272 males, 203 females; mean age 64.8 ± 11.9 years). Postoperative complications occurred in 85 patients (17.8%). Multivariate analysis revealed low SMI (P = 0.025) and hypoalbuminemia (P = 0.048) were independent risk variables for these complications. The median follow-up was 51 months (IQR, 37.5-62.25). Low IMAT (HR 2.919, 95% CI: 1.423-5.985, P = 0.003) and high SMI (HR 0.450, 95% CI: 0.247-0.821, P = 0.009) were independent prognostic variables for RFS. Considering the original cohort, the AUCs for 1-, 3-, and 5-year RFS were 0.885, 0.867, and 0.868, and for the validation cohort, the AUCs for 1-, 3-, and 5-year RFS were 0.784, 0.817, and 0.897. The nomogram demonstrated strong predictive performance for RFS.

[CONCLUSION] Sarcopenia is a standalone predictor for postoperative complications and RFS in patients with CC, whereas myosteatosis independently predicts RFS. The nomogram provides valuable support for clinical decision-making and holds the potential to improve patient outcomes.