Recurring cystosarcoma phyllodes associated with breast carcinoma.

A 59-year-old patient, who had had recurring giant fibroadenomas and cystosarcoma phyllodes over a 36-year period, presented with cystosarcoma phyllodes and adenocarcinoma of the breast. Only seven other well documented instances of the coexistence of these lesions have been reported. The prognosis and treatment of adenocarcinoma was not affected by coexisting cystosarcoma phyllodes.