Keimyung Medical Journal, Vol.1(1) : 149-157, 1982
Malignant cystosarcoma phyllodes is a rare fibroepithelial breast tumor, which constitutes less than 1% of all breast tumors, but still is the most frequent sarcoma of the breast. In 1833 Johannes Muller first introduced the term cystosarcoma phyllodes and emphasized the benignity of the lesion. The lesion was considered innocent untill 1931 when Lee & Pack described the first case of metastasis, thus establishing the malignant potential of cystosarcoma phyllodes. It is generally accepted that the malignant component is of stromal orgin and that in most major series the incidence of malignancy varies from 20 to 30%. The management of cystosarcoma phyllodes shows discouraging results, irrespective of therapeutic efforts and histological characteristiecs. Poor correlation between the histologic features and biological behavior of the tumor has recently been emphasized. The recurrence rate is high with figures of up to 30% in benign series, and the majority of malignant tumors run a fatal course. In the past 5 years, we have experienced 3 cases of malignent cystosarcoma phyllodes diagnosed in the Department of Pathology, Presbyterian Medical Center, Keimyung University. Included is a recurrent case of malignant cystosarcoma phyllodes with interval of 2 years. Detailed clinical histories and pathological findings were described on each of these cases. A brief review of literature on this entity was entertained.