Prognostic Significance of Sarcopenic Obesity in Colorectal Cancer Surgery: A Retrospective Cohort Study

Sarcopenic obesity (SO), the coexistence of reduced skeletal muscle mass and excess visceral fat, represents a distinct metabolic phenotype increasingly recognized in surgical oncology. Its prognostic role in colorectal cancer (CRC) surgery remains insufficiently defined, particularly in the Asian populations.

In this retrospective cohort study, 923 patients undergoing curative CRC resection between 2017 and 2023 were evaluated. Preoperative computed tomography at the L3 level quantified skeletal muscle index and visceral fat area. Sarcopenia and visceral obesity were defined according to the Asian Working Group for Sarcopenia and Japanese criteria, respectively. Patients were classified into four phenotypes: normal, obesity, sarcopenia, and SO. Postoperative complications, overall survival (OS), and recurrence-free survival (RFS) were analyzed using logistic regression, Kaplan-Meier, and Cox proportional hazards models.

The incidence of postoperative complications increased progressively from normal (11.9%) to obesity (17.3%), sarcopenia (20.5%), and SO (27.5%) (P < 0.001). SO independently predicted both overall (odds ratio = 2.56, P = 0.003) and severe (odds ratio = 3.21, P = 0.004) complications. Patients with SO had the poorest 5-y OS and RFS (log rank P < 0.001), confirmed by multivariable Cox analysis (OS: hazard ratio = 1.92; RFS: hazard ratio = 1.87).

Sarcopenic obesity independently predicts postoperative morbidity and adverse long-term survival following curative CRC surgery. Incorporating computed tomography-derived body composition assessment into routine preoperative evaluation may improve risk stratification and enable targeted prehabilitation, ultimately enhancing surgical and oncologic outcomes.