A multicenter retrospective series of 70 breast sarcomas (malignant cystosarcoma phyllodes (25), osteosarcoma (12), liposarcoma (10), stromal sarcoma (8), angiosarcoma (7), mixed types sarcoma (4), malignant histiocytoma (3), leiomyosarcoma (1)) was reviewed. The average follow-up was 5.9 years. Diagnostic tests (palpation, mammography, sonography and cytology) were poorly sensitive, and a large proportion of cases, appearing as regular, sharp bordered, rounded masses were diagnosed as benign fibroadenomas. Surgery (limited (29), mastectomy (41)) was the treatment of choice. Axillary nodes were rarely involved (2 of 31) at pathologic staging. No significant predictors of local recurrences (12 cases) were observed although recurrences were more frequent in larger lesions (0-20 mm = 1.1%, 21-50 mm = 1.7%, > 50 mm = 6.1% women-year) and in cases treated with limited surgery (limited surgery 4.6%, mastectomy 2.0% women-year). Distant metastases (16 cases) were less frequent in malignant cystosarcoma phyllodes or liposarcoma patients, but no other significant predictors of distant metastases were evidenced. Five-year disease-free or overall survival was 50% or 66%, respectively. The study confirms that breast sarcomas are rare, difficult to diagnose, but can be cured by surgical treatment in a considerable proportion of cases.