Factors associated with pericolic fat stranding of colon cancer on computed tomography colonography

BACKGROUND: Pericolic fat stranding on computed tomography (CT) scans has been an important feature for staging colon cancer. However, the factors associated with pericolic fat stranding have not been elucidated to date. PURPOSE: To determine factors associated with pericolic fat stranding of colon cancer on CT colonography (CTC). MATERIAL AND METHODS: Overall, 150 patients with 155 colon cancer lesions were retrospectively assessed by two radiologists for pericolic fat stranding on CTC. Circumferential proportion of the tumor (CPtumor; <50%, 50–75%, and ≥75%), longitudinal length, depth of invasion (≤T2, T3, T4), lymph node and distant metastasis, and lymphovascular invasion were recorded. Univariate and multivariate logistic regression analyses were performed between pericolic fat stranding and each factor. Multi-group comparisons were performed for the CPtumor and depth of invasion. RESULTS: Pericolic fat stranding was identified in 57 lesions (36.8%). Univariate analysis revealed significant associations of pericolic fat stranding with all factors (P < 0.027), except for lymph node metastasis (P = 0.087). Multi-group comparisons revealed that pericolic fat stranding was more frequent with increasing CPtumor (P < 0.001); however, no significant differences were observed beyond subserosal infiltration (P = 0.225). Logistic regression analysis revealed the CPtumor (<75% vs. ≥75%; P = 0.008, <50% vs. 50–75%; P = 0.047) and longitudinal length (P = 0.001) as explainable variables. CONCLUSION: Pericolic fat stranding identified on CT images of colon cancer is demonstrated more frequently with increasing circumferential proportion of the tumor and longitudinal length.