Metaplastic carcinoma of the breast clinical presentation, treatment results and prognostic factors.

Metaplastic carcinoma of the breast (MCB) is a rare form of cancer containing mixture of epithelial and mesenchymal elements in variable combinations. Few and conflicting clinical data are available in the literature addressing optimal treatment modalities, prognosis and outcome. A retrospective study was conducted to review all patients with MCB diagnosed and treated at King Faisal Specialist Hospital and Research Center between 1994-2004. The aim is to describe patient's clinicopathologic features and to analyze treatment results. Nineteen female patients were studied. The median age was 48 years (range, 14-58). The median tumor size was 9 cm (range, 3-18). Stage distribution was II in 8 patients, III in 9 and IV in 2. Nine cases were identified as purely epithelial and 10 (53%) as mixed epithelial and mesenchymal metaplasia. Hormone receptors were positive in only 2 patients. Modified radical mastectomy performed in 11 patients and 15 underwent axillary node dissection. Adjuvant chemotherapy was given to 9 patients and postoperative radiotherapy to 8. Twelve patients relapsed with median time of relapse of 12 months (range, 2-28). At a median follow-up of 21 months (range, 7-83), the 3-year event free survival (EFS) and overall survival for the patients diagnosed with loco-regional disease were 15% and 48% respectively. Tumor size correlated significantly with EFS. MCB is an aggressive form of breast cancer associated with poor outcome, high incidence of local recurrence and pulmonary metastases. The disease tends to be estrogen/progesterone receptor negative. Tumor size has an important impact on outcome. The best treatment approach is yet to be defined.