Is visceral obesity associated with colorectal cancer? The first volumetric study using all CT slices

Abstract

Purpose: We aimed to examine the possible relationship between abdominal adiposity parameters and the presence of colorectal cancer (CRC) and between these adiposity parameters and various histopathologic findings of the tumor.

Methods: A total of 60 control subjects and 111 CRC patients, 63 with early-stage and 48 with advanced-stage disease, were enrolled. Medical data and abdominopelvic computed tomography (CT) examinations of each study group were retrospectively reviewed. Abdominal adiposity parameters, including visceral adipose tissue (VAT) volume, subcutaneous adipose tissue (SAT) volume, and total adipose tissue (TAT) volume, were calculated on all slices of the CT examinations with specialized software, and results for each study group were compared. Adiposity parameters were also compared with tumor histopathologic findings.

Results: We found lower VAT and higher SAT volumes in advanced-stage CRC patients, compared with the early-stage group. However, this relationship was not statistically significant (P = 0.721 for VAT and P = 0.432 for SAT volumes). We detected significantly lower VAT and SAT volumes in the early-stage CRC group compared with the control group (P = 0.014 for both). There was no significant relationship between TAT volumes and the study groups (P = 0.06). No statistically significant relationship was detected between adipose tissue parameters and histopathologic features of the CRC group (P > 0.05).

Conclusion: We found statistically significant lower VAT and SAT volumes in patients with early-stage CRC compared with the control group. Volumetric adipose tissue measurements may be more accurate than area measurements and can easily be performed on abdominopelvic CT examination, which is the routine imaging modality for CRC patients.

Figure 1. a–f

Abdominal adipose tissue measurements by using specialized software. Coronal (a–e) and axial (f) oral- and IV-contrasted abdominopelvic CT images. Image (a) shows marking of the visceral abdominal adipose tissue by using a plus sign (+) provided by the software. After the marking, similar density areas are determined, and image (b) is formed by the software. Image (b) demonstrates the final visceral adipose tissue mass (dark green area) which is selected by the software after manual editing by the researchers. Image (c) shows marking of the subcutaneous abdominal adipose tissue with a plus sign (+). After the marking, similar density areas are determined, and image (d) is formed by the software. Image (d) shows the final subcutaneous adipose tissue mass (dark red area), which is selected by the software after manual editing by the researchers. Images (e) and (f) demonstrate the visceral (dark green area) and subcutaneous (dark red area) abdominal adipose tissue together. On image (f), a transverse colon mass is readily seen.

Figure 2

Abdominal adipose tissue measurements by using specialized software. The picture demonstrates the distribution of visceral (orange) and subcutaneous (pink) adipose tissues determined by the software in the sagittal, coronal, and axial projections. The lower left image is the volume-rendered image showing the visceral, subcutaneous, and total amount of abdominal adipose tissue in milliliters.