Visceral Fat Quantitated From CT Colonography Is Associated With the Presence of Colorectal Polyps

Abstract

Background: An adenomatous polyp is known as a precancerous lesion of colorectal cancer. Detection and removal of adenomatous polyps are essential for colon cancer prevention. Previous studies have found the association between obesity and adenomatous polyp using many parameters.
 Objective: To determine the association between visceral fat visualized on computed tomography (CT) colonography (CTC) and colorectal polyps.
 Methods: This retrospective case-control study consisted of 280 adult subjects who underwent colon cancer screening by CTC at Ramathibodi Hospital; 129 cases with CT detected colorectal polyps who underwent polypectomy within 6 months, and 151 control subjects who were negative for significant polyps on CTC. Visceral fat areas of all subjects were measured on CT at the umbilical level by a semiautomatic method. Statistical analysis was performed to ascertain associations with the presence of colorectal polyps.
 Results: Of 280 adult subjects, there were classified into 4 groups; no polyps (n = 151), hyperplastic polyp (n = 23), low-risk adenomatous polyp (n = 75), and high-risk adenomatous polyp (n = 31). The mean visceral fat areas in 4 groups were 125.1 ± 55.7 cm2, 140.2 ± 63.8 cm2, 147.9 ± 74.2 cm2, and 156.6 ± 63.7 cm2, respectively. There were statistically significant differences in these means visceral fat between the no polyp group and both the low-risk and high-risk adenomatous polyp groups. In multivariate analyses, subjects who had visceral fat areas more than 168.60 cm2 were more likely to have polyps than subjects whose visceral fat areas were less than 93.65 cm2 (P < .05).
 Conclusions: Visceral fat was positively associated with the presence of adenomatous colorectal polyps.