Recurrent and metastatic cystosarcoma phyllodes.

During a 30 year period (1950 to 1980), 42 patients with cystosarcoma phyllodes were seen at the Mayo Clinic. Ten patients (24 percent) had recurrence of metastasis. The malignant or metastatic potential could not be identified or predicted by histologically evaluating tumor contour, stromal atypia, or mitotic activity. Spread was chiefly by a hematogenous route, and no patient with metastasis survived. Five of the 10 patients died from their disease 2 to 7 years after treatment. Simple mastectomy appears to be the surgical treatment of choice.