Risk of malignancies among asymptomatic postmenopausal women with thickened endometrium: A cohort study.

The risk of malignancies and related factors among asymptomatic postmenopausal women with thickened endometrium in transvaginal sonography (TVS) are unclear.In this longitudinal study at a tertiary teaching hospital, all medical records of hysteroscopy were searched and retrospectively reviewed according to age, TVS results and diseases coded as International Classification of Diseases version 10. Asymptomatic postmenopausal women with endometrial thickness ≥5 mm from January 2006 to January 2016 were included. A follow-up was provided up to January 2017.Four hundred eighty-eight patients were included with a median endometrial thickness of 8 mm (range 5-30) in TVS. The most common pathologic findings were polyps (51.0%) and normal endometrium (34.2%). Fifteen (3.1%) and 10 cases (2.0%) had endometrial intraepithelial neoplasia (EIN) and carcinoma. Patients with carcinoma had significantly more abnormal serum CA125, thicker endometrium, and more lesions with positive Doppler flow signals. In receiver operating characteristic curve analysis, endometrial thickness of 12 mm had the best predictive ability for malignancies. In multivariate analysis, endometrial lesion with positive Doppler flow signals in TVS was the only independent factor for EIN/carcinoma (odds ratio [OR] 8.0, 95% confidence interval [CI] 1.4-45.1) and for carcinoma (OR 16.0, 95% CI 1.3-192.8). After a median follow-up of 45 months, carcinoma occurred in 1 of 35 (2.8%) women with repeated thickened endometrium.Among asymptomatic postmenopausal women with thickened endometrium, the risk of EIN and malignancy was minimal but worth of long-term follow-up. Endometrial lesions with positive Doppler flow signals in TVS suggested a high risk of malignancy.