Determining the inter- and intraobserver reproducibility of the diagnosis of endometrial hyperplasia subgroups and well-differentiated endometrioid carcinoma in endometrial curettage specimens.

Background: Many studies have attempted to identify histologic features that help to distinguish atypical hyperplasia from hyperplasia without atypia and well-differentiated endometrioid carcinoma of the endometrium; however, few have evaluated the reproducibility of these diagnoses.

Methods: Five pathologists independently reviewed 100 endometrial curettage specimens chosen to represent the spectrum of proliferative lesions of the endometrium. This included simple hyperplasia, complex hyperplasia, atypical hyperplasia, and well-differentiated endometrioid carcinoma.