MR Imaging Findings of Tamoxifen- associated Uterine Adenosarcoma: Report of Two Cases

Adenosarcoma of the uterus is a mixed epithelial-mesenchymal tumor containing benign glandular epithelial component with sarcomatous mesenchymal stroma. This rare tumor accounts for only 8% of all uterine sarcomas (1). It has been suggested that some cases of the uterine adenosarcoma may be associated with hyperestrinism due to the administration of tamoxifen and prior radiation exposure (1-3). Tamoxifen is an antiestrogen drug which is widely used as adjuvant therapy for breast cancer. However, it has been associated with proliferative abnormalities of the endometrium including endometrial hyperplasia, endometrial polyps, and cancer (2). Toremifene, a synthetic analogue of tamoxifen, also has been thought to be associated with endometrial cancer (7). To our knowledge, there have been only a few case reports with documented MRI of uterine adenosarcoma including two radiologic reports of tamoxifen related adenosarcoma (2-6). Here, we report two cases of uterine adenosarcoma with regard to MRI features in patients receiving antiestrogen therapy for breast cancer. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Received: February 26, 2015 Revised: March 23, 2015 Accepted: March 25, 2015