Objective: To compare the diagnostic accuracy of ultrasonographic endometrial thickness and outpatient hysteroscopy, to establish the most appropriate exam for the diagnosis of endometrial cancer in postmenopausal women with abnormal uterine bleeding (AUB). The secondary aim was to develop a multivariable approach considering clinical history as an added value for these diagnostic procedures.
Methods: This prospective study was conducted on 220 consecutive postmenopausal patients with AUB, who underwent ultrasonographic evaluation of endometrial thickness, outpatient hysteroscopy and endometrial biopsy. Evaluation of sensitivity, specificity, positive and negative predictive value was performed. Receiver operator characteristic curve (ROC) was calculated to assess the global performance of ultrasonographic measurement of endometrial thickness and diagnostic hysteroscopy as tests for detecting endometrial cancer and atrophy.
Results: Histological findings for <4 mm level revealed that atrophy was present in 48 (65%) and in 2 cases (2.7%) endometrial cancer was found; for > or = 4 mm values polyps and myomas were present in 86 (59%) and there were 11 (7.5%) endometrial cancer. Sensibility and specificity for trans-vaginal ultrasound, with a cut-off value > or = 4 mm, was 55.6% and 49.7% while positive predictive value was 83.3% and negative predictive value 98.1% (ROC curve 0.597). Hysteroscopy revealed sensitivity 100%, specificity 49.6%, positive predictive value 81.3% and negative predictive value 100% (ROC curve 0.993).
Conclusions: In conclusion, endometrial thickness <4 mm can miss malignancies but trans-vaginal ultrasound remains the first line diagnostic procedure in postmenopausal women without AUB, because it is not invasive and has high sensitivity for detecting endometrial cancer and other endometrial disease; according to our experience, outpatient hysteroscopy with biopsy is mandatory in all postmenopausal women with AUB.