简介：AbstractBackground:Endometrial cancer is one of the most common malignancies of the reproductive system. Effective and cost-effective screening method for populations at high risk is not available. This study aimed to investigate specimen adequacy and the influencing factors in microscale endometrial sampling biopsy and to evaluate the diagnostic accuracy and medical cost of biopsy in endometrial cancer and atypical hyperplasia screenings in comparison with hysteroscopic endometrial biopsy.Methods:A total of 1551 patients at high risk for endometrial lesions who required hysteroscopic endometrial biopsy from November 2017 to August 2018 were included. Microscale endometrial sampling biopsy was performed, followed by hysteroscopic endometrial biopsy. We evaluated the specimen adequacy and influencing factors of microscale endometrial sampling. Diagnostic consistency between microscale endometrial sampling biopsy and hysteroscopic endometrial biopsy was evaluated. The sensitivity, specificity, positive predictive value, and negative predictive value of microscale endometrial sampling biopsy in screening for endometrial cancer and atypical hyperplasia were analyzed, and the medical costs of the two procedures were compared.Results:The specimen adequacy was 81.2%. Patient age, menopausal status, endometrial thickness, and endometrial lesion type were correlated with specimen adequacy. There was good consistency in distinguishing benign and malignant endometrial diseases between microscale endometrial sampling biopsy and hysteroscopic biopsy (kappa 0.950, 95% CI 0.925-0.975). The sensitivity, specificity, positive predictive value, and negative predictive value of microscale endometrial sampling biopsy were 91.7%, 100.0%, 100.0%, and 99.3% for endometrial cancer screening, respectively, and 82.0%, 100.0%, 100.0%, and 99.4% for atypical hyperplasia screening. The medical cost of endometrial sampling biopsy was only 22.1% of the cost of hysteroscopic biopsy.Conclusions:Microscale endometrial sampling biopsy is a minimally invasive alternative technique for obtaining adequate endometrial specimens for histopathological examination. It has the potential to be used in detecting endometrial cancer and atypical hyperplasia with high efficiency and low cost.