Comparison of diagnostic accuracy between endometrial curettage and aspiration biopsy in patients treated with progestin for endometrial hyperplasia: a Korean Gynecologic Oncology Group study.

objectiveTo compare the diagnostic accuracy of dilatation and curettage (D&C) versus endometrial aspiration biopsy in follow-up evaluation of patients treated with progestin for endometrial hyperplasia (EH).

methodsA prospective multicenter study was conducted from 2015 to 2018. Patients with EH were treated with progestin, one of the following three treatment regimens: oral medroxyprogesterone acetate (MPA) 10 mg/day for 14 days per cycle, continuous MPA 10 mg/day or the levonorgestrel-releasing intrauterine system (LNG-IUS). At 3 or 6 months of treatment, endometrial tissues were obtained via 2 methods in each patient: aspiration biopsy, followed by D&C. The primary outcome was the consistency of the histologic results between the 2 methods. The secondary outcome was the regression rate at 6 months of treatment.

resultsThe study population comprised 65 patients (55 with non-atypical hyperplasia, 10 with atypical hyperplasia). During the follow-up, a comparison of the pathologic results from aspiration biopsy and D&C was carried out for the 65 cases. Thirty-eight cases were diagnosed as EH by D&C. Among these, only 24 were diagnosed with EH from aspiration biopsy, for a diagnostic concordance of 63.2% (κ=0.59). Forty-four patients were followed up at 6 months, and the regression rate was 31.8% (14/44). Responses were obtained for 41.7% (5/12) of the cyclic MPA group, 58.3% (7/12) of the continuous MPA group and 10% (2/20) of the LNG-IUS group.

conclusionAs a follow-up evaluation of patients treated with progestin for EH, aspiration biopsy is less accurate than D&C and might not be a reliable method.

trial registrationClinicalTrials.gov Identifier: NCT02412072.