[Mixed metaplastic cancer of the breast].

Basic criteria for making morphologic diagnosis were identified as a result of a study of 4 cases of mixed metaplastic cancer of the breast: segments of the chondroid and osteoid tissue intermittent with structures of infiltrative ductal cancer. Tumor presented as acini-like structures and areas consisting of polymorphous cells with necrosis and calcification. Osteogenesis occurred in some areas. Distant metastases were observed in two cases at months 160 and 127 after treatment. These patients died at months 169 and 134 after treatment as a result of tumor progression. It is recommended that similar treatment be given for mixed metaplastic cancer and infiltrative ductal cancer of the breast.