Endometrial cancer arising from atypical complex hyperplasia: The significance in an endometrial biopsy and a diagnostic challenge

OBJECTIVE We investigated the features of endometrial hyperplasia with concurrent endometrial cancer that had been diagnosed by endometrial sampling. Further, we attempted to identify an accurate differential diagnostic method. METHODS We retrospectively studied 125 patients who underwent a diagnostic endometrial biopsy or were diagnosed after the surgical treatment of other gynecological lesions, such as leiomyoma or polyps. Patients were diagnosed between January 2005 and December 2013 at Busan Paik Hospital. Clinical and histopathological characteristics were compared in patients who had atypical endometrial hyperplasia with and without concurrent endometrial cancer. RESULTS The patients were grouped based on the final pathology reports. One hundred seventeen patients were diagnosed with endometrial hyperplasia and eight patients were diagnosed with endometrioid adenocarcinoma arising from atypical hyperplasia. Of the 26 patients who had been diagnosed with atypical endometrial hyperplasia by office-based endometrial biopsy, eight (30.8%) were subsequently diagnosed with endometrial cancer after they had undergone hysterectomy. The patients with endometrial cancer arising from endometrial hyperplasia were younger (39.1 vs. 47.2 years, P=0.0104) and more obese (body mass index 26.1±9.6 vs. 23.8±2.8 kg/m(2), P=0.3560) than the patients with endometrial hyperplasia. The correlation rate between the pathology of the endometrial samples and the final diagnosis of endometrial hyperplasia was 67.3%. CONCLUSION In patients with atypical endometrial hyperplasia, the detection of endometrial cancer before hysterectomy can decrease the risk of suboptimal treatment. The accuracy of endometrial sampling for the diagnosis of concurrent endometrial carcinoma was much lower than that for atypical endometrial hyperplasia. Therefore, concurrent endometrial carcinoma should be suspected and surgical intervention should be considered in young or obese patients who present with atypical endometrial hyperplasia.