Sarcomas of the breast are uncommon, accounting for less than 1% of all primary malignancies. Among these tumors, malignant fibrous histiocytoma (MFH) is very rare. Two cases of this neoplasm are reported, with histological findings and surgical treatment. The issue of radiation-induced lesions after surgery for carcinoma and the necessity for a correct preoperative diagnosis is examined. A review of the available literature evaluates the histopathological and biological features of MFH of the breast, for which there are no prospective trials, owing to the rarity of this kind of neoplasm. The extent of surgery or role of axillary lymph nodes dissection and multimodality therapy are discussed.