Endometrial Intraepithelial Neoplasia Clinical Correlates and Outcomes

Abstract

To estimate cancer outcome and outcome predictors of women with endometrial intraepithelial neoplasia (EIN). Outcomes of women with first diagnosis of EIN ("index biopsy") were determined by follow-up pathology. Patient characteristics were correlated with EIN regression, EIN persistence, and progression to cancer. Fifteen percent (95% confidence interval [CI] 9.8-20.8%, 26 of 177) of index EIN biopsy samples had concurrent cancer. Of the women with cancer-free index EIN biopsy samples and follow-up by hysterectomy or more than 18 months of surveillance, 25% (95% CI 18.4-33.3%, 36 of 142) showed regression, 35% (95% CI 27.4-43.7%, 50 of 142) showed persistence, and 39% (95% CI 31.3-48.0%, 56 of 142) showed progression. Nonwhite ethnicity and progestin treatment reduced cancer outcomes (odds ratio [OR] 0.16, 95% CI 0.03-0.84 and OR 0.24, 95% CI 0.08-0.70, respectively), whereas body mass index greater than 25 increased malignant outcomes (body mass index 25 or higher, OR 3.05, 95% CI 1.10-8.45). Endometrial intraepithelial neoplasia confers a high risk of cancer, but individual patient outcomes cannot be predicted. Management should include exclusion of concurrent carcinoma and consideration of hysterectomy.