Can the Measurement of Endometrial Thickness by Transvaginal Ultrasound Be Used for the Prediction of Endometrial Cancer in Asymptomatic Post-Menopausal Women? A Systematic Review of the Literature

Aim: To assess the diagnostic efficiency of transvaginal ultrasonography (TVUS) measurement for discrimination between benign and malignant endometrial conditions in asymptomatic postmenopausal women. Moreover, to evaluate the cut-off risk for endometrial cancer in postmenopausal women, as a screening tool. Materials and Methods: In order to identify all studies related to the systematic review question, a detailed search strategy that took into account all important aspects of the clinical question and an appropriate study design was developed. Two reviewers independently assessed study characteristics, methodological details, and eligibility. Search strategy for evidence included two major medical databases PubMed and Cochrane Database of Systematic Reviews. Key words used were: asymptomatic postmenopausal women, atypical hyperplasia, endometrial cancer, transvaginal ultrasound, screening, and endometrial thickening. Results: The significance of the thickness of the endometrium beyond 4 mm is not the same as for symptomatic postmenopausal women, and extrapolating guidelines from postmenopausal bleeding to asymptomatic population is not valid. In asymptomatic postmenopausal women, the risk of cancer is approximately 6.7% when endometrium is > 11 mm. which is comparable to the 5% risk in symptomatic postmenopausal women for a 5-mm cut-off. If endometrium measures <= 11 mm, endometrial biopsy is not necessary. A postmenopausal asymptomatic woman with known risk factors for endometrial cancer like diabetes, obesity, use of unopposed estrogen or tamoxifen, will have a higher risk of cancer even with the same TVUS measurement. The diagnostic accuracy of hysteroscopy was optimal for all intrauterine pathologies and endometrial polyps are the most frequent findings in asymptomatic postmenopausal women with an endometrium measuring > 5 mm. conclusions: The results do not justify the need for routine use of transvaginal ultrasound as a screening test for endometrial cancer as it is quite rare in asymptomatic postmenopausal women. When deciding how to manage imaging findings, individual patient risk needs to be analyzed in order to avoid over-treatment.