Pure uterine lipoma.

Pure fatty tumors of the uterus are extremely rare and usually develop in postmenopausal women. We present the first reported Japanese case of a pure uterine lipoma, in which a preoperative diagnosis was made by magnetic resonance imaging (MRI) and was pathologically confirmed postoperatively. As in our case, MRI is currently the best modality for determining the internal architecture of a tumor and the presence of fat. Because of the benign nature of a uterine lipoma, such an approach can avoid unnecessary surgery in asymptomatic patients.