Determining a threshold measurement of endometrial thickness for asymptomatic postmenopausal women: A tertiary centre case series.

Abstract

An incidental finding of a thickened endometrium on ultrasound in the postmenopausal patient without bleeding is a common presentation to gynaecological services; however there is limited evidence to guide clinical practice as to when hysteroscopic evaluation and endometrial sampling is required. To determine the endometrial thickness at which endometrial sampling is indicated in asymptomatic postmenopausal women referred with thickened endometrium on ultrasound. A single-centre retrospective case series of postmenopausal women without bleeding undergoing hysteroscopy was conducted. Logistic regression was used to examine the association between a range of variables and pre-malignant or malignant pathology and endometrial thickness. The optimal endometrial thickness threshold was identified to maximise model sensitivity. A total of 404 postmenopausal women were included in this study, having undergone a hysteroscopy at the study site between 1 July 2008 and 30 June 2018. The mean (SD) age of patients at presentation was 65 (9.09) years and the mean body mass index was 29.86 kg/m2 (6.52). Of these women, nine (2.2%) were diagnosed with endometrial carcinoma and seven (1.7%) had endometrial hyperplasia with atypia. The most common histopathological finding was of a benign endometrial polyp (153: 37.9%). When including hyperplasia with or without atypia in histopathology of interest, a cut-off of ≥9 mm provides the greatest sensitivity (83.3%) and specificity (63.8%) for a diagnosis of pre-malignant or malignant pathology (classification accuracy of 64.8%; area under the receiver operating characteristic: 0.7358, 95% CI: 0.6439, 0.8278) in this cohort. Using an endometrial thickness of ≥9 mm can be used as a cut-off for endometrial sampling in postmenopausal women without bleeding.