RELATION OF ENDOMETRIAL CANCER RISK TO PAST AND CONTEMPORARY BODY-SIZE AND BODY-FAT DISTRIBUTION

In a multicenter case-control study that included 403 cases and 297 co ntrols, we examined the relation of past and contemporary body size, i ncluding body fat distribution, to the risk of endometrial cancer. The relative contributions of past and contemporary body size were assess ed by examining weight and height histories provided by the subjects. Anthropometric indicators thought to reflect early environmental influ ences (e.g., height and sitting height), current weight, and fat distr ibution patterns were measured directly. Height was not a risk factor for endometrial cancer, but inexplicably, sitting height was inversely associated with risk. Weight during early adulthood appeared to be di rectly related to disease risk, but the association was explained by c ontemporary weight and thus weight gain during adulthood. While contem porary weight was associated with risk of endometrial cancer, the effe ct was restricted to those in the top quartile. Women whose measured w eight at interview exceeded 78 kg had 2.3 times the risk of those weig hing less than 58 kg (95% confidence interval, 1.4 to 3.7). Upper-body obesity (waist-to-thigh circumference ratio) was a risk factor indepe ndent of body weight. After adjustment for weight, the relative risks of endometrial cancer across increasing quartiles of upper-body obesit y were 1.0, 1.5, 1.8, and 2.6 (P for trend < 0.001). These data indica te that both obesity and the distribution of adipose tissue accumulate d during adult life increase endometrial cancer risk substantially.