Published online May 26, 2022. doi: 10.12998/wjcc.v10.i15.5064
Peer-review started: December 6, 2021
First decision: January 25, 2022
Revised: February 23, 2022
Accepted: March 27, 2022
Article in press: March 27, 2022
Published online: May 26, 2022
Processing time: 168 Days and 22.3 Hours
Metaplastic breast carcinoma (MBC) is a rare subtype of invasive breast cancer comprising malignant epithelial and mesenchymal cells. Compared with other invasive breast cancers, MBC is not only histologically distinctly heterogeneous but also has a rapid and aggressive growth pattern, which leads to a significant risk of recurrence and mortality.
In this study, we report the case of a patient with a large left breast mass diagnosed with bilateral invasive ductal carcinoma in both breasts after a preoperative core needle aspiration biopsy of the bilateral breast mass. The patient received neoadjuvant chemotherapy and underwent bilateral breast modified radical mastectomy. Postoperative pathology suggested carcinosarcoma with predominantly chondrosarcoma in the left breast and invasive ductal carcinoma (luminal B) in the right breast. As the patient did not achieve complete pathological remission after six cycles of neoadjuvant chemotherapy, we administered six months of intensive capecitabine treatment. Then the patient was switched to continuous treatment with endocrine therapy using letrozole + goserelin, and the patient is currently in stable condition. However, as MBC of the breast is concurrently diagnosed with chondrosarcoma differentiation, our case is sporadic.
Given the variety of immunohistochemical types of bilateral breast cancer, achieving effective chemotherapy should be a key research focus.
Core Tip: Metaplastic breast carcinoma (MBC) is a rare subtype of invasive breast cancer comprising malignant epithelial and mesenchymal cells, with low incidence. Our patient with a large left breast mass was diagnosed with carcinosarcoma with predominantly chondrosarcoma in the left breast, and postoperative pathology also suggested invasive ductal carcinoma in the right breast. The current knowledge of MBC is limited, particularly in patients with concurrent bilateral breast cancer. Clinicians should fully consider the situation of bilateral mammary glands and formulate a comprehensive treatment plan for such patients.