Population attributable risk for endometrial cancer in northern Italy.

The population attributable risk for endometrial cancer has been estimated in relation to its four major risk factors (overweight, estrogen replacement therapy, diabetes and hypertension) using data on 528 cases and 1626 controls collected within the framework of a hospital-based case-control study conducted since 1981 in the greater Milan area, northern Italy. Over 30% of the endometrial cancer cases diagnosed in the study population could be attributed to overweight, 10% to postmenopausal estrogen replacement therapy, and similar proportions (around 10%) to hypertension and diabetes. The overall estimate including the joint effect of the two conceptually preventable factors (overweight and estrogen use) was 40%, while further inclusion of diabetes and hypertension, which are not easily preventable per se but are still closely linked to 'westernization', indicated that over 50% of cases were attributable to the combined effect of these four factors. The validity of these findings, in strict terms, is limited to this area from northern Italy. However, they can be taken as a general indication of the scope for prevention of endometrial cancer in other southern European populations, sharing similarities in lifestyle and pattern of hormonal replacement therapy use.