Pleomorphic Invasive Lobular Carcinoma of the Male Breast: Two Case Reports with Opposite Hormone Receptor Status.

Male breast cancer represents <1% of breast cancers, with invasive lobular carcinoma in male breast being extremely rare. Only four cases of male breast with pleomorphic lobular carcinoma (PLC) are reported in literature. Here, we report two additional cases. The first case was a 63-year old male presenting with a left neck mass, progressive facial numbness, bilateral cervical lymphadenopathy, and brain metastasis. Neck mass and left breast biopsies confirmed left breast PLC with metastasis. The second case was a 79-year old male with a left breast mass; biopsy and subsequent mastectomy showed PLC. Awareness of this entity is important for rendering an accurate diagnosis, especially in the setting of metastases.