A huge metaplastic breast carcinoma with chest wall invasion and pulmonary metastasis: a rare case report.

Metaplastic breast carcinoma (MBC) is a diverse group of invasive breast carcinoma, in which the neoplastic epithelium differentiates toward squamous cells or mesenchymal looking elements, including but not restricted to spindle, osseous and chondroid cells. MBC was formally considered a distinct pathological pattern by WHO classification of breast tumors in 2000. We report the case of a 49-year-old Syrian female who presented to our hospital due to a painful huge mass in her right breast. Radiographic and clinical findings were highly indicative of breast carcinoma. Therefore, a core needle biopsy was performed, and surprisingly, microscopic examination suggested the diagnosis of soft tissue sarcoma, whereas immune stains confirmed the diagnosis of metaplastic carcinoma. We aim to introduce a challenging case that clarifies the rarity of this tumor, and the methods we used in diagnosing, examining and treating this malignancy.