RESUMEN
Breast carcinosarcoma, also known as metaplastic breast cancer, is one of the rarest types of breast cancer. It is an aggressive and poor prognostic breast cancer compared to triple-negative breast cancer. Due to the lack of specific and prescribed treatment, it could threaten patients' lives, especially women worldwide. There are various diagnostic methods, such as multiple imaging and pathology methods, to diagnose breast cancers. Still, considering the common appearance characteristic of this type of breast cancer with other types, histopathology is the most definitive way. There is no standard neoadjuvant or adjuvant chemotherapy for this rare type of breast cancer. In this article, we reported the case of a 62-year-old female with a final diagnosis of metaplastic breast carcinoma and her surgical and medical treatment method.