Metaplastic Breast Carcinoma: Analysis of Clinical and Pathologic Characteristics - A Case Series.

OBJECTIVE: Metaplastic breast cancer (MBC) is a rare type of breast cancer that is considered to be clinically aggressive. The clinical significance and prognostic risk factors of MBC are limited. This study comprises a retrospective analysis of the clinical and pathologic findings of a series of patients treated for MBC. MATERIALS AND METHODS: The files of 657 patients who underwent surgery because of breast cancer at our clinic were examined and the data found on 11 patients who were diagnosed as having MBC were analyzed. RESULTS: With a median age of 56 years, all patients were postmenopausal and presented with a palpable mass on physical examination. Symptoms of ulceration and skin involvement were seen in only one patient. Eight patients were diagnosed as having squamous cell carcinoma (SCC), and 3 had both SCC and osseous differentiation. The median diameter was 3.8 cm (max. 14 cm; min. 1.5 cm). Lymph node metastasis was detected in 5 (45%) patients. Progesterone (PR) and estrogen (ER) were both negative in 11 (100%) patients and 10 (90.9%) patients, respectively, and CerbB2 was negative in 7 (63.6%) patients. Patients were followed up for a median period of 15 months (range, 6-40 months); at the end of which, 10 patients survived and one died of cardiac arrest at 7 months post-operatively. No instances of local recurrence or distant organ metastasis were found in any patients. The overall patient survival rate was 90%. CONCLUSION: There is no consensus on the clinical significance or best treatment approach for metaplastic carcinoma. In our study, patients with MBC were of advanced age, had tumors with large margins, high negativity for hormone receptors, and moderate- to well-differentiated histology.