[Malignant phyllodes tumor with differentiation to liposarcoma. A report of a case and bibliographic review].

Phyllodes tumor represents less than 1% of breast tumors and 2 to 3% of the fibroepithelial tumors. The malignancy characteristics are the excessive growth and the stromal atypia with numerous mitosis. The stromal component of the phyllodes tumor has potential to cause metaplasia to bone tissue, cartilage, and to smooth and striated muscle, including their respective malignant neoplasms. The liposarcomatous differentiation of phyllodes tumor is extremely rare. We present the case of an unusual breast tumor diagnosed as phyllodes tumor, with sarcomatous changes on its stroma, which consists of pleomorfic and myxoid liposarcoma. We also comment some generalities about clinical and diagnostic aspects, as well as anatomopathological, therapeutic, and prognostic characteristics related to the current literature.