Abstract: Metaplastic carcinoma of the breast is a rare type of breast cancer in which tumor cells can differentiate into squamous,spindle,or sarcomatoid mesenchymal components,with the sarcomatoid type being less than 0.1%.Clinically,it often presents as a rapidly growing painless mass,and imaging studies lack specificity,making it prone to misdiagnosis,often necessitating surgical biopsy for confirmation.It is predominantly triple-negative in phenotype,responds poorly to chemotherapy,and has a poor prognosis.Treatment mainly involves modified radical surgery,complemented by anthracyclines and platinum-based chemotherapy.This disease has a high risk of hematogenous metastasis and recurrence,with significant variability in lymph node metastasis rates;thus,the extent of dissection should be determined by sentinel lymph node biopsy,and close postoperative follow-up is required.

Key words: metaplastic breast cancer; osteosarcoma; malignant tumor; treatment