Recurrent endometrial polyps in postmenopausal breast cancer patients on tamoxifen

Objectives. Endometrial polyps are the most common endometrial pathology described in association with postmenopausal tamoxifen exposure, with an incidence of up to 10.7% of malignancy. Some women tend to develop recurrent polyps. However, no one has yet described any risk factors for the development of recurrent endometrial polyps in postmenopausal breast cancer tamoxifen-treated patients. Methods. We compared various clinical features of 64 postmenopausal breast cancer tamoxifen-treated patients with a primary endometrial polyp (Group I), with those of 27 similar patients with recurrent polyps (Group 2). Results. Previous exposure to hormone replacement therapy was significantly more common and duration of tamoxifen treatment, up to the diagnosis of primary endometrial polyp, was significantly shorter in Group II patients (P = 0.0217 and P = 0.0148, respectively). Logistic regression analysis revealed that the combination of shorter tamoxifen exposure before the diagnosis of primary polyp, lower parity, lower menopausal age at the diagnosis of primary polyp, and higher years of tamoxifen treatment was found to increase significantly the risk of developing recurrent endometrial polyps. Any additional year of tamoxifen treatment may increase by fivefold the risk of developing recurrent polyps. There was no significant difference in ultrasonographic endometrial thickness measured before resection of the primary polyps in both groups and before the resection of recurrent polyps in Group II. Conclusions. Previous use of HRT, shorter duration of tamoxifen exposure, and additional years of tamoxifen treatment may significantly increase the risk of developing recurrent endometrial polyps in postmenopausal breast cancer tamoxifen-treated patients.