Correlation between peritumoral fat space blur on preoperative abdominal enhanced CT and postoperative complications in colorectal cancer: a single-center retrospective study

To investigate the association between blurred peritumoral fat planes on preoperative contrast-enhanced abdominal CT and postoperative complications in colorectal cancer, and to evaluate its predictive value.

This study was a single-center retrospective analysis that consecutively enrolled 135 patients with colorectal adenocarcinoma who underwent curative surgery at Anhui West Health Vocational College Affiliated Hospital between February 2019 and December 2024. Two radiologists, blinded to clinical outcomes, independently assessed the degree of peritumoral fat plane blurring on preoperative CT scans using a 0-3 grading scale. Clinicopathological, surgical, and postoperative complication data were collected. Univariate and multivariate logistic regression analyses were performed to evaluate the association between fat plane blurring and postoperative complications. The predictive performance was assessed using receiver operating characteristic (ROC) curve analysis, and subgroup analyses were conducted.

A total of 135 patients were included, with a mean age of 66.3±9.8 years, and 63.0% were male. The distribution of peritumoral fat plane blurring grades was as follows: grade 0 in 22 patients (16.3%), grade 1 in 14 (10.4%), grade 2 in 40 (29.6%), and grade 3 in 59 (43.7%). The overall postoperative complication rate was 61.5% (83/135), and the rate of severe complications (Clavien-Dindo grade ≥III) was 44.4% (60/135). The degree of fat plane blurring was significantly associated with both overall complications (P<0.001) and severe complications (P<0.001), demonstrating a clear dose-response relationship. Multivariate analysis identified the fat plane blurring grade as an independent predictor of postoperative complications (OR=2.59; 95% CI: 1.70-3.95; P<0.001). ROC curve analysis yielded an area under the curve (AUC) of 0.750 for predicting complications. Using a cutoff of grade ≥2, the sensitivity was 81.6% and the specificity was 75.8%. Subgroup analyses confirmed that this association remained consistent across different tumor locations and surgical approaches.

Blurred peritumoral fat planes on preoperative CT are an independent predictor of postoperative complications in colorectal cancer, demonstrating moderate predictive performance. This imaging feature can serve as a practical tool for preoperative risk assessment, aiding in the identification of high-risk patients and guiding individualized perioperative management.