Relationship of visceral adipose tissue to recurrence of adenomatous polyps

Insulin is a growth factor for colorectal cancer. Visceral adipose tissue (VAT) is strongly associated with insulin levels, and insulin and visceral obesity have been associated in cohort studies with colorectal cancer. The aim of this investigation was to determine whether VAT is associated with recurrence of adenomatous polyps, the precursor to colorectal cancer.

As an ancillary study to the Polyp Prevention Trial, a randomized clinical trial that evaluated the effect of a low-fat, high-fiber, high vegetable and fruit diet on adenomatous polyp recurrence, subjects at one clinical center underwent measurement of VAT with a single-slice CT scan through the L4-L5 interspace. The scan was performed around the time of the subject's year 4 colonoscopy that determined adenoma recurrence.

Of 119 subjects, 44 of 84 men (52%) and 16 of 35 women (46%) had a recurrent adenoma (p= 0.51). Body mass index (BMI) and weight at baseline and at year 4 colonoscopy were unrelated to adenoma recurrence. In a multivariate model including visceral fat quartile, remote history of polyps, gender, age, and randomization group, only remote history of polyps was statistically significantly associated with recurrent adenoma with a relative risk of 4.6 (95% CI 1.7, 12.4, p= 0.001). There was no consistent monotonic trend of increased or decreased risk of recurrence as one ascended quartiles of adipose tissue for visceral, subcutaneous, or total abdominal fat.

In this study, no association between visceral adipose tissue and adenomatous polyp recurrence was observed. Further study and exploration of the role of VAT in adenoma progression is required.