[Cystosarcoma phylloides of the breast. Analysis of 58 cases].

Cystosarcoma phylloides (c.p.) is a rare fibroepithelial neoplasm of the mammary gland exhibiting considerable histological variations ranging from the aspect of hypercellular fibroadenoma to that of pleomorphic sarcoma. In this study, 58 cases of c.p. were graded according to their histology into 3 groups of increasing malignancy-benign tumors: 23 cases (42%), borderline tumors: 16 cases (27%) and malignant tumors: 18 cases (31%). Their clinical properties and evolution have been compared. These tumors were found exclusively in women, most often during the 5th and 6th decade of life (age range from 19 to 81 years). In two thirds of the cases, the history of the disease was shorter than 6 months. The symptoms were generally scant. Only in 2 cases were severe local lesions observed. The postoperative clinical course has been followed for at least 5 years in 32 instances. Recurrences were observed in 5 patients, the histology being as a rule the same as that of the primary tumor. The 12 patients with benign tumors are well 5 years or more after operation. One of the patients presenting a malignant tumor died of lung embolism soon after mastectomy. 2 out of 10 patients with borderline tumors died within 6 years with metastases of the mammary tumor. Our analysis confirms the experience that c.p. are relatively benign but often recurring neoplasms that rarely disseminate. As far as prognosis and treatment are concerned, tumors of questionable dignity should be considered malignant. To avoid such vague terms as "benign or malignant c.p." we support OBERMANN'S suggested separation of c.p. into "cellular fibroadenoma" and "periductal fribrosarcoma". Wide local excision for small and benign tumors is recommended. All other forms require simple mastectomy. Prophylactic dissection of the axillary lymph nodes is not necessary as these tumors usually disseminate hematogenously. Roentgen therapy or chemotherapeutic agents are not useful in treatment.