Spindle cell carcinoma of breast:a clinicopathological analysis of 2 cases

Objective To discuss the histopathological characteristics,diagnosis and differential diagnosis of spindle cell carcinoma of the breast.Methods Two cases of spindle cell carcinoma of the breast and relative literatures were reviewed.Both tumors were investigated by histopathology,and immunohistochemical staining.Results Two cases occurred in women,and their age was 46 and 60 years,respectively.Tumor size ranged from 2.0-2.8 cm.The both tumors were composed predominantly of spindle cells with a cluster of epithelioid cells.The lesion of one case showed the cellular fascicular spindle cell architecture with atypia,but the other consisted of bland spindle cells with densely hyaline collagenous tissue,mimicking fibromatosis.Both spindle cells and epithelioid cells expressed CK,CK5 /6,34βE12 and p63.One case recurred 5 months after surgery.Conclusions Spindle cell carcinoma is a unique metaplastic carcinoma in the breast and easy to be misdiagnosed.It should be distinguished from fibromatosis,phylloides tumor and fibrosarcoma.The overall prognosis of spindle cell carcinoma of breast is poor with high frequency of local recurrence and distant metastasis,except fibromatosis-like spindle cell carcinoma.