A CASE WITH BONE-AND CARTILAGE-METAPLASTIC BREAST CANCER

An 85-year-old woman was seen at the hospital because of a tumor of the left breast which had been noticed one month before. The malignant findings were obtained by mammography and ultrasonography, and a diagnosis of carcinoma was made by needle biopsy. The cancer which was detected in A-area was 2.8×3.1cm in size, and stage II was diagnosed though lymph node was impalpable (T2a, N0, M0). Atypical mammectmy (Br+Ax) was carried out. Histopathologically it was bone- and cartilagemetaplastic breast cancer associated with cartilage tissue. The transfer type for undifferentiation was considered from canalicular structure of the undifferentiated tumor cell between site of the adenocarcinoma and cartilage tissue. It was considered that cartilage tissue was metaplastized from epithelial cell because cartilage tissue could be found in the undifferentiated cell which remained characters of the epithelium. Immunohistologically epithelial membrane antigen (EMA) in the component of the epithelial metaplasia and partial undifferentiated cells was positive.