Phyllodes tumors are frequently large (4 to 5 cm) at diagnosis. About half are malignant, accounting for < 1% of breast cancers. Between 20% and 35% of these tumors recur locally, and distant metastases occur in 10 to 20% of patients.
Usual treatment of a phyllodes tumor is wide excision, but a mastectomy may be more appropriate if the mass is large or histology suggests cancer. Radiation therapy may be recommended in some cases.
Prognosis is good unless metastases (usually pulmonary) are present.