Objective: The aim of this study was to screen for disorders and to histologically classify endometrial biopsy specimens from 2964 perimenopausal and postmenopausal women who were candidates for hormonal replacement therapy.
Study design: Endometrial biopsy specimens were obtained with a Vabra aspiration curette, processed by standard methods, and stained by hematoxylin and eosin and special methods to reveal subtle features of the endometrium.
Results: Of the endometrial biopsy specimens, 68.7% were atrophic, 23.5% were proliferative, 0.5% were secretory, 0.6% were hyperplastic, 0.07% were adenocarcinoma, and 6.6% were insufficient for classification. Three independent senior microscopists agreed on the classification of each biopsy specimen.
Conclusion: The number of patients is the largest ever screened for a single hormone replacement therapy study. The low yield of endometrial cancer indicates that biopsies are unnecessary before hormone replacement therapy is initiated in asymptomatic women.