CT-Derived Predictors of Incisional Hernia Following Colorectal Cancer Resection: A Systematic Review

Background/Objectives: To systematically review computed tomography (CT)-derived body composition and morphological predictors of incisional hernia (IH) following colorectal cancer (CRC) resection. Methods: PubMed/MEDLINE, Embase, Scopus, Web of Science, Cochrane Library, and CINAHL were searched from inception to May 2026, supplemented by grey literature searching. Studies reporting CT-derived predictors of IH after CRC resection were eligible. Two independent reviewers screened records, extracted data, and assessed risk of bias using the Newcastle-Ottawa Scale. Given heterogeneity in CT metrics, exposure definitions, and statistical models, findings were synthesised narratively, and certainty of evidence was assessed using GRADE. Results: Nine retrospective cohort studies including 2392 patients met the inclusion criteria. IH incidence ranged from 4.5% to 33.6%. Visceral adiposity was the most frequently evaluated predictor, although only two studies reported standalone adjusted odds ratios for the elevated visceral fat area. Subcutaneous adiposity, sarcobesity, and novel umbilical morphological metrics, including umbilical fat, intraperitoneal thickness, and enlargement of the umbilical orifice, were independently associated with IHs in individual studies. Umbilical fat showed the largest adjusted effect estimate (hazard ratio 6.56; 95% CI 2.73-15.70). Quantitative pooling was not performed as fewer than three studies reported comparable adjusted estimates for any predictor. Certainty of evidence was low to very low across all predictor categories. Conclusions: Preoperative CT may provide clinically useful, but currently low-certainty, body composition data for IH risk stratification after CRC resection. Prospective multicentre validation using standardised CT protocols is required before routine clinical implementation.