Forty-nine patients with cystosarcoma phyllodes (CP), aged 13-81 years, (mean 35.2 years) were studied. Tumor size ranged from 1.9 to 14 cm (mean 5.2 cm). Mean follow-up period was 11.3 years. Tumors were histopathologically graded as benign, borderline or malignant. Forty-two tumors were diagnosed as benign; 4 borderline and 3 malignant. Six patients had recurrent disease within 6 years of their first surgery. Statistical analysis showed that age was not a significant factor for predicting recurrence or malignant histopathology. Five patients with relapse had borderline or malignant tumors larger than 4 cm. The histopathologic diagnosis was concordant with the clinical course. Multivariate analysis showed that tumor size and histology were significant and independent factors for disease-free interval. Breast-conserving surgery with a wide tumor-free margin is preferred in CP, and close follow-up is advised in cases with malignant or borderline histopathology and tumors larger than 4 cm.