Value of endometrial thickness assessed by transvaginal ultrasound for the prediction of endometrial cancer in patients with postmenopausal bleeding

Histological confirmation of endometrial cancer by dilatation/curettage (D/C) in women with postmenopausal bleeding (PMB) can be challenging due to anesthesiological and/or surgical risks. Thus, less invasive methods for diagnostics are required to identify patients with minimal risk for endometrial cancer (EC) to avoid unnecessary surgical intervention. The objective of this single-center cohort study was to assess the diagnostic validity of transvaginal ultrasound (TVUS) measurements of endometrial thickness (ET) in patients with PMB for the detection of EC. A retrospective analysis of data from patients presenting between January 2005 and August 2014 at the Department of Obstetrics and Gynecology, University Hospital Ulm, Germany, with PMB and subsequent D/C was performed. Complete data with TVUS documentation of ET and histological results of tissue samples were available from 254 patients. In addition, data on age, body mass index (BMI), ASA-score, diabetes, hypertension, and hematological laboratory values (for a smaller subsample) were recorded. To identify independent risk factors, a multivariate logistic regression with endometrial cancer as binary response variable (yes/no) was performed. Diagnostic efficacy data for different ET cutoff points (ae1 to ae26 mm) were obtained by a receiver operator characteristic (ROC) curve analysis. The multivariate logistic regression revealed a significant independent predictive value for age and ET. However, none of the analyzed ET cutoff points showed optimal diagnostic validity, as all cutoff points with sensitivity rates above 90% (ae1 to ae5 mm) had false positive rates of 70% and higher. There is no ET cutoff point that provides good diagnostic accuracy and/or reliably excludes the presence of endometrial cancer in patients with PMB. Thus, our data analysis supports the actual German approach of histological evaluation of any PMB to confirm or exclude EC.