A Validated Estimate of Visceral Adipose Tissue Volume in Relation to Cancer Risk.

Background: Despite the recognized role of visceral adipose tissue (VAT) in carcinogenesis, its independent association with cancer risk beyond traditional obesity measures remains unknown due to limited availability of imaging data.

Methods: We developed an estimation equation for VAT volume (L) using Elastic Net Regression based on demographic and anthropometric data in a subcohort of participants in the UK Biobank (UKB; N = 23,148) with abdominal MRI scans. This equation was externally validated in 2,713 participants from the 2017-2018 National Health and Nutrition Examination Survey (NHANES) according to sex, age, and race groups. We then applied the equation to the overall UKB cohort of 461,665 participants to evaluate the prospective association between estimated VAT (eVAT) and cancer risk using Cox proportional hazards models. We also calculated the population attributable risk (PAR) of cancer associated with eVAT and BMI.

Results: eVAT showed a high correlation with measured VAT in internal and external validations (r = 0.81-0.86). During a median 12-year follow-up in the UKB, we documented 37,397 incident cancer cases; eVAT was significantly associated with elevated risk of obesity-related and individual cancers, independent of BMI and waist circumference. PAR for total cancer associated with high (quartiles 2-4 vs 1) eVAT (9.0-11.6%) was higher than high BMI (Q2-4 vs 1; 5.0-8.2%).

Conclusions: eVAT showed robust performance in both UKB and NHANES and was associated with cancer risk independent of BMI and waist circumference. This study provides a potential clinical tool for VAT estimation and underscores that VAT can be an important target for cancer prevention.