A case of malignant fibrous histiocytoma after breast conserving therapy for breast cancer.

A 45-year-old woman with malignant fibrous histiocytoma (MFH) of the breast following breast conserving therapy (BCT) is described. She noticed a lump in her left breast 52 months after BCT for breast cancer. The lump was excised and nodular fasciitis was initially diagnosed. However, the tumor recurred locally 4 times in the next 18 months. MFH was finally diagnosed. This case is considered to be radiation-induced sarcoma. The risk of radiation-induced sarcoma after BCT seems to be very low, however careful follow-up is necessary.