Adiposity levels may predict CRC risk

High adiposity levels are associated with the risk of colorectal cancer (CRC), suggest the results of a systematic review. However, standardization is necessary to improve understanding of the link between CRC and adiposity to enable comparisons across papers.

A team of investigators searched the databases of Medline, Scopus, Embase, Cinahl, and Central for studies that assessed adiposity measures; included incident data for any diagnosed malignant stage of CRC, colon cancer, or rectal cancer; and assessed adults aged >18 years. They also evaluated articles for bias using the National Institutes of Healthy study quality assessment tools.

Fifteen articles across 10 studies met the eligibility criteria. Of these, three reported a significantly positive association, one showed a negative association, while the rest had nonsignificant and positive associations.

Measures varied depending on the tool used, and the following tools were employed to obtain body composition data: bioelectrical impedance, computerized tomography, dual-energy x-ray absorptiometry, and ultrasound. The most frequently used measures were total body fat mass, percent fat, and abdominal visceral and subcutaneous adipose tissues.

Overall, greater adipose levels showed a positive association with a higher risk of CRC. The significance and robustness of these relations varied by body composition variable, measurement technique, tumour location, and sex.

“Additionally, a balance among precision, accessibility, and cost of measurements must be struck,” the investigators said.