VISCERAL OBESITY AND BREAST-CANCER RISK

Background. The risk for breast cancer and the sex hormone abnormaliti es noted in breast cancer patients have been demonstrated in women wit h upper body fat obesity. The objective of this study was to determine if the visceral component of upper body fat obesity was correlated wi th breast cancer risk. Methods. A case-control study of 40 consecutive ly enrolled women with breast cancer and 40 community-based age, weigh t, and waist circumference-matched control subjects was conducted. The ; areas of visceral fat, subcutaneous fat, and total fat were measured using computed tomography at the L-4 vertebral body. Calculations of relative risk for breast cancer were based on these fat compartments. Results. Patients with breast cancer had a significantly greater visce ral fat area (P = 0.01), visceral-to-total-fat area ratio (VT ratio) ( P < 0.001) and significantly lower subcutaneous-to-visceral-fat area r atio (Sir ratio) (P < 0.001) compared with the matched controls. The r elative risk for breast cancer increased with increasing VT ratio (les s than or equal to 0.24 = 1.0; >0.24 = 9.5) (P < 0.0001) and decreasin g SV ratio (greater than or equal to 3.64 = 1.0; <3.64 = 8.5) (P = 0.0 002). Conclusions. Visceral obesity, as assessed by computed tomograph y, was a significant risk factor for breast cancer in women matched fo r age, weight, and waist circumference. Comparing the VT ratio for bot h groups, breast cancer patients had 45% more visceral fat compared wi th matched control subjects.