[Chondrosarcomatous metaplastic carcinoma of the breast, a rare tumor]. / Carcinoma metaplásico condrosarcomatoide de mama, una entidad inusual.

ABSTRACT

Metaplastic carcinomas of the breast are uncommon, accounting for less than 0.2% of all breast cancers. Clinically and radiologically, metaplastic carcinomas are indistinguishable from typical ductal carcinomas, and the diagnosis is made histologically by the finding of a mesenchymal component. We present a case of chondrosarcomatous metaplastic breast carcinoma whose definitive diagnosis required immunohistochemical techniques to confirm the malignant epithelial component of the tumor. Accurate diagnosis is important because this tumor behaves differently it usually spreads through the blood (whereas typical epithelial carcinomas spread through the lymph vessels), metastases present during follow-up rather than before diagnosis, and the five-year survival rate is 35%.