Abstract:Breast tumors are the most common tumors of epithelial origin. Some tumors or tumor-like lesions of the breast may display a morphology similar to mesenchymal tumors predominated by spindle cells. However, such morphology is apt to be confused with others due to lack of the characteristic histopathology. This paper reviews some spindle cell lesions in the breast, in an attempt to provide theoretical evidences for the differentiation diagnosis of breast tumors and tumor-like lesions.