Atypical endometrial hyperplasia arising in an endometrial polyp in a tamoxifen-treated breast cancer patient in whom endometrial cytology was negative for cancer—A case report—

Abstract

Background : Estrogen is involved in the development of breast and endometrial cancers, and tamoxifen, an antiestrogen, is associated with an increased risk of development of endometrial cancer. Recently, tamoxifen use has been suggested to be associated with the development of endometrial tumors. We present a case of atypical endometrial hyperplasia arising in an endometrial polyp in a tamoxifen-treated breast cancer patient in whom endometrial cytology was negative for cancer.
Case : A 43-year-old woman, para 2, was referred to us for hypermenorrhea. She had been treated by tamoxifen for four years. Transvaginal ultrasonography revealed an endometrial polyp, and endometrial cytology was negative for cancer. Transcervical resection was performed for the endometrial polyp. Histological examination confirmed the diagnosis of atypical endometrial hyperplasia in the endometrial polyp. Thereafter, we performed laparoscopic vaginal hysterectomy and bilateral salpingoophorectomy.
Conclusion : Patients using tamoxifen are at a high risk of development of endometrial neoplasms. Atypical endometrial hyperplasia can arise inside an endometrial polyp. Thus, care must be exercised in patients with endometrial polyps even if the endometrial cytology is negative.