Mixed epithelial/mesenchymal metaplastic carcinoma(carcinosarcoma)of breast:two cases report and literature review

Objective:To investigate the clinical and pathological features,diagnosis and prognosis of breast mixed epithelial/mesenchymal metaplastic carcinoma(carcinosarcoma).Methods:The histopathology and immune phenotype of two cases of breast carcinosarcoma in our hospital were observed,studied and discussed,and related literatures were reviewed.Results:Microscopic examination showed that pathological changes were well-demarcated.One case was poorly differentiated invasive ductal carcinoma and chondrosarcoma component;the major component of the other case was malignant fibrous histocytoma,and a few ductal carcinoma in situ were observed on the edge of the lesion.Immunohistochemically,the chondrosarcoma cells of the first case were positive for Vimentin and S-100,negative for CK,the carcinoma cells were positive for CK,negative for ER,PR and C-erbB-2,the sarcoma cells of the second case were positive for Vimentin,CD68 and AACT,negative for CK-pan,P63,CK-low,CK7,CK19,CK5/6 and CK34βE12,the carcinoma cells in situ were positive for CK-pan,negative for ER,PR and C-erbB-2.Conclusion:The primary mixed epithelial/mesenchymal metaplastic carcinoma(carcinosarcoma)in the breast gland was rare,whose diagnosis should be differentiated with the primary sarcoma,malignant phyllodes tumor,carcinoma sarcomatodes,promoting fiber hyperplastic cancer in the breast.