Value of sonographic endometrial findings in patients with breast cancer under tamoxifen therapy

Tamoxifen is utilized as adjuvant therapy in women diagnosed with breast cancer. In these patients, despite its positive risk/benefit ratio, tamoxifen may cause secondary effects on the endometrium, with increased risk of malignant diseases. So, the first question to be answered is: “Does tamoxifen increase the incidence of endometrial abnormalities?” The literature presents two meta-analysis-studies that have been developed with this objective. Both have demonstrated that long-term use of tamoxifen in patients with breast cancer is associated with a higher incidence of uterine diseases: the studies developed by Tabor et al. and Cohen — 48 papers and 106 papers, respectively. The first one has demonstrated 330 women with endometrial cancer, and other 3,483 without cancer. Tamoxifen may lead to a range of histological alterations in the endometrium, including cystic atrophy, endometrial polyp, hyperplasia, atypical hyperplasia, endometrial adenocarcinoma, and, also, sarcoma and uterine serous carcinoma in a pre-existing polyp. The increase in the risk for endometrial cancer developed in polyps is estimated between 2.5% and 10%, although, according to other authors, it is a little lower. Aggressive endometrial carcinoma and uterine metastasis from infiltrating ductal carcinoma of the breast also have been described. Other authors have not found alterations in the endometrial thickness or increase in the rate of polyps and hyperplasia. The rate of active endometrium preand post-tamoxifen therapy has been estimated in 10%. Estrogenic effect on the en-