Composite TyG-Inflammation Index as a Preoperative Biomarker of Metabolic-Inflammatory Vulnerability in Colorectal Cancer Surgery: Associations With Postoperative Complications and Myosteatosis.

Systemic inflammation and insulin resistance are increasingly recognized as key determinants of perioperative vulnerability in patients with colorectal cancer. The Composite TyG-Inflammation Index (CTI), which integrates the triglyceride-glucose index and C-reactive protein, has recently emerged as a marker of metabolic-inflammatory dysfunction.

However, its clinical relevance in colorectal cancer surgery has not been established.

This study aimed to evaluate the association of preoperative CTI with postoperative complications and myosteatosis in patients undergoing elective curative colorectal cancer surgery within an Enhanced Recovery After Surgery (ERAS) pathway. This prospective observational cohort study included 100 consecutive patients undergoing elective curative colorectal cancer surgery within an ERAS program. Preoperative assessment included nutritional evaluation, handgrip strength, bioelectrical impedance analysis, and computed tomography-based body composition analysis at the third lumbar vertebra. CTI was calculated using fasting triglycerides, glucose, and C-reactive protein concentrations.

The primary outcome was overall postoperative complications during the index hospital admission. Secondary analyses evaluated the association between CTI and myosteatosis. Multivariable logistic regression models were adjusted a priori for age and Charlson Comorbidity Index, with additional sensitivity analyses using alternative clinically relevant adjustment models. Higher CTI values were independently associated with an increased risk of overall postoperative complications (OR 7.96; 95% CI 2.83-22.42; p < 0.001).

CTI was also independently associated with the presence of myosteatosis (OR 5.85; 95% CI 2.22-15.38; p < 0.001). Receiver operating characteristic analysis showed good discriminatory performance for postoperative complications (AUC 0.814) and myosteatosis (AUC 0.815). Patients with myosteatosis had significantly higher CTI values, supporting a close relationship between metabolic-inflammatory dysfunction and impaired muscle quality. Preoperative CTI was independently associated with postoperative complications and myosteatosis in patients undergoing curative colorectal cancer surgery.

These findings suggest that CTI may be a simple and readily available biomarker of metabolic-inflammatory vulnerability with potential utility for preoperative risk stratification and identification of patients at increased risk of adverse surgical outcomes.