Endometrial polyps and hyperplasia as risk factors for endometrial carcinoma. A case-control study of curettage specimens.

As part of a comprehensive case-control study, the impact of previous endometrial pathology on the risk of developing endometrial carcinoma was investigated. The study comprised 254 consecutive women with histopathologically confirmed cancer of the uterine body in a well-defined population, and their age-matched controls. Ninety-eight (39%) of the patients and 81 (32%) of the controls had previously undergone endometrial curettage. More than one previous curettage was positively associated with endometrial carcinoma (odds ratio = 2.5; 95% CL = 1.4-4.5). Endometrial abnormalities in previous curettage specimens occurred significantly more often among carcinoma patients (57%) than among controls (25%) (odds ratio = 4.0; 95% CL = 2.0-8.0). Twelve patients, but no controls, had adenomatous hyperplasia and this hyperplasia antedated the cancer diagnosis by a mean of 4.6 years. Endometrial polyps were present significantly more often in patients (20%) than in controls (10%) (odds ratio = 3.4; 95% CL = 1.3-9.3). The present results suggest that both of these conditions are risk factors for endometrial carcinoma. Among women who had undergone endometrial curettage more than 4 years after the menopause, 19 out of 30 patients, but none out of 7 controls, showed abnormality in the curettage specimens. Postmenopausal women with endometrial abnormality should thus be regarded as being at risk of developing endometrial carcinoma.