When is it necessary to perform biopsy in asymptomatic postmenopausal women with incidental finding of thickened endometrium?

Objective To determine the cutoff value for endometrial thickness (ET) that prompts a biopsy in asymptomatic postmenopausal women with an incidental finding of thickened endometrium, and to develop a risk prediction model. Methods This is a retrospective cohort analysis of the clinical records of the Hysteroscopic Center of Fu Xing Hospital, Capital Medical University, Beijing, China. We collected asymptomatic postmenopausal women who presented with an ET of >= 4 mm (double-layer) as an incidental finding. We stratified the participants into non-malignant and malignant groups based on pathology results and assessed differences between the two groups. A receiver operating characteristic curve (ROC) was used to identify the cutoff value of ET for predicting endometrial malignancy. Logistic regression models were also constructed to predict the risk of malignancy. Results A total of 581 consecutive eligible cases were included. The optimal cutoff value for ET was 8 mm, with a maximum area under the curve (AUC) of 0.755 (95 % CI: 0.645-0.865). In addition to ET, the regression model incorporated diabetes, blood flow signal, BMI, and hypertension to predict the risk of malignancy. A ROC curve constructed for the model yielded an AUC of 0.834 (95 % CI: 0.744-0.924). Conclusion It is reasonable to offer hysteroscopy and visually-directed endometrial biopsy for asymptomatic postmenopausal women when ET is 8 mm or above. For those with an ET between 4 and 8 mm, further decision to perform biopsy should be determined on an individual basis, considering risk factors and blood flow signals of the endometrium.