VARIATION IN BODY-FAT DISTRIBUTION AND BREAST-CANCER RISK IN THE FAMILIES OF PATIENTS WITH BREAST-CANCER AND CONTROL FAMILIES

Background. The pattern of body fat distribution in women has been cor related with the risk of developing breast and endometrial cancer. The authors determined whether body fat distribution varied between first -degree relatives of patients with breast cancer and in cancer-free fa milies by comparing the body fat distribution of first-degree relative s of patients with breast cancer with age and Quetelet Index-matched c ontrols. Methods. Fifty-six first-degree relatives of newly diagnosed patients with breast cancer were compared with 56 controls (non-cancer family members) matched for age and Quetelet Index and were studied f or variation in body fat distribution. Anthropometric measurements wer e taken for the abdomen, thigh, suprailiac, subscapular, biceps, and t riceps skinfold thickness; waist and hip circumference; weight; and he ight. The distribution of body measurements and derived ratios in both case and control family members were compared using the Student t tes t. Results. A significant variation in body fat distribution occurred among first-degree relatives in breast cancer and control families. In families with a history of breast cancer, first-degree family members were found to have significantly greater waist:hip ratio (P < 0.001) compared with controls without family history matched for age and Quet elet Index. Other variables indicating upper body fat localization, su ch as abdomen and suprailiac skinfold were significantly greater in fa mily members of patients with breast cancer compared with controls. Co nclusions. A marked variation occurred in body fat localization among first-degree relatives of patients with breast cancer and in cancer-fr ee families. This finding implies a variation in breast cancer risk in these families. Identifying family members with upper body fat distri bution in breast cancer families would allow targeting of these indivi duals for energetic screening and risk factor reduction interventions.