Endometrial polyp surveillance in premenopausal breast cancer patients using tamoxifen

OBJECTIVE To describe the endometrial pathologic lesions in premenopausal breast cancer patients with a history of tamoxifen (TMX) use. METHODS We retrospectively reviewed the medical records of 120 premenopausal breast cancer patients with a history of TMX use that had undergone a gynecological examination. RESULTS Among 120 patients, 44.2% (n=53) were asymptomatic with an endometrial thickness ≥5 mm, as assessed by transvaginal ultrasonography. Of the patients that reported abnormal uterine bleeding, 5% (n=6) had an endometrial thickness <5 mm and 20% (n=24) had an endometrial thickness ≥5 mm by transvaginal ultrasonography. The final group of patients were asymptomatic, but showed an abnormal endometrial lesion, such as an endometrial polyp, by transvaginal ultrasonography (30.8%, n=37). Of the 56 benign lesions that were histologically reviewed, 50 (41.7%) were endometrial polyps, 3 (2.5%) were submucosal myomas, 2 (1.7%) were endometrial hyperplasias, and 1 (0.8%) was chronic endometritis. There were 64 (53.3%) other non-pathologic conditions, including secreting, proliferative, and atrophic endometrium, or in some cases, there was insufficient material for diagnosis. In our data, only one case was reported as a complex hyperplasia without atypia arising from an endometrial polyp, and one patient was diagnosed with endometrioid adenocarcinoma. CONCLUSION For premenopausal breast cancer patients with a history of TMX use, the majority of the patients were asymptomatic, and endometrial polyps were the most common endometrial pathology observed. Therefore, we believe that endometrial assessment before starting TMX treatment, and regular endometrial screening throughout TMX treatment, are reasonable suggestions for premenopausal breast cancer patients.