Cystosarcoma phyllodes.

Recurrence and metastases of a cystosarcoma phyllodes are poorly correlated with the histologic type and treatment used. There is some evidence, however, that the prognosis is more favorable for small tumors and minimal cellular atypism. Local excision seems to be associated with a higher incidence of recurrence of the tumor. Metastases can develop later from what appears primarily a benign, as well as a malignant, type. Mastectomy as primary treatment was not always effective in preventing the local recurrence of the tumor. If the tumor recurred after mastectomy, it gave rise to fatal metastases. The recurrence of the tumor after local excision is secondary to microscopic foci retained after enucleation. If a local excision is done, it should include a wide margin of mammary tissue around the tumor. Wide local excision, for small, slow growing and clinically benign tumors can be used as a first operation, with wider re-excision and later mastectomy if the tumor recurs. Large and rapidly growing tumors that suggest malignant disease should be treated primarily by mastectomy.