High-grade endometrial stromal sarcoma after tamoxifen therapy for breast cancer

A case of high-grade endometrial stromal sarcoma, confined into an intrauterine polypoid growth, in a woman with a history of breast cancer who was treated with adjuvant tamoxifen. Based on the findings, a high-grade endometrial stromal sarcoma was diagnosed. The patient underwent a total hysterectomy and bilateral salpingo-oophorectomy with multiple omental biopsies. Pathological examination on multiple uterine sections showed the absence of residual tumor cells in the uterus. The endometrium showed patterns of glandular cystic hyperplasia. After 14 months of follow-up, the patient is well and free of disease. In deciding if tamoxifen therapy is warranted, all potentially life-threatening adverse events associated with tamoxifen should be considered, including endometrial adenocarcinoma or uterine sarcoma.