Metaplastic breast carcinoma with osseous differentiation: A report of a rare case and literature review

Metaplastic matrix-producing breast carcinoma is a type of metaplastic breast carcinoma (MBC), which is a rare malignancy, accounting for 0.2-1% of breast carcinomas. A 52-year-old female visited a hospital because of a palpable painless mass in the right breast and was diagnosed with Breast Imaging Reporting and Data System (BI-RADS) category 4A via ultrasound (US) with a suspected positive lymph node at the right axillary region. Excision of the breast mass was performed and histopathologically confirmed that it was MBC with osseous differentiation. No distant metastasis was revealed before a modified radical mastectomy; however, metastasis to a lymph node of the right axillary region was observed (1/22). She received six cycles of TEC scheme chemotherapy (docetaxel, epirubicin, and cyclophosphamide, 21 days) and 5 weeks of radiotherapy (48 Gy/25 f/5 days a week), but without any follow-up examinations since radiotherapy. Twenty-four months after surgery, distant metastases to lungs and liver were confirmed and died 3 months later. This case provides valuable information for clinicians on MBC and suggests that further examination or biopsy should be performed to US BI-RADS 4A masses before surgery. In addition, regular postoperative follow-up plays important roles in detecting metastases early and improving prognosis.

Automated summary

A rare case of metaplastic matrix-producing breast carcinoma is reported, diagnosed as BI-RADS category 4A via ultrasound, with lymph node metastasis observed in the right axillary region. The patient underwent surgery, chemotherapy, and radiotherapy, but developed distant metastases to the lungs and liver 24 months after surgery and died 3 months later. This case highlights the importance of further examination and biopsy for BI-RADS 4A breast masses before surgery, as well as regular postoperative follow-up.