Metaplastic Breast Carcinoma in a Male Patient: A Rare Case Report

Abstract

Metaplastic breast carcinoma is known to be a rare entity among female breast cancers. It is even rarer for a male patient to be diagnosed with this variant of breast carcinoma, with fewer than ten reported cases in the literature. We report an extremely rare case of metaplastic breast carcinoma in a male patient, with distant metastases, without axillary nodal disease. He presented with a left breast lump rapidly increasing in size over three weeks. Mammogram and ultrasound revealed a round heterogeneous complex mass with internal cystic components. The mass had posterior acoustic enhancement. Biopsy confirmed metaplastic breast carcinoma of the spindle cell subtype. The immunohistochemistry showed that it was triple negative for estrogen receptor (ER), progesterone receptor (PR), Human epidermal growth factor receptor-2 (HER2) receptor status. Staging CT showed pulmonary metastases and chest wall disease. In view of the patient’s poor pre-morbid functional status, the decision was made for best supportive care and the patient eventually succumbed to the disease shortly after two months. Metaplastic breast carcinoma is an aggressive breast carcinoma with poor prognosis. Despite rapid increase in size clinically, it can demonstrate non-aggressive radiological features. Complex echogenicity with solid-cystic components may be demonstrated on ultrasound, likely due to haemorrhage or cystic necrosis. Although there may be distant metastases, axillary nodal disease is not frequent. Radiologists should be aware of this disease entity, its imaging findings, and clinical features despite its rare occurrence.