A case of male breast cancer relapsing with pleural effusion

Male breast cancer (MBC) is a rare entity, accounting only for 0.6% of all breast cancers. Its causes are incompletely understood. Pleural effusion is usually known as a metastasis of advanced breast cancer in women. However, it has never been described as a recurrence of MBC. We report the case of a 84 year-old man diagnosed with a breast cancer in 2014, initially treated with a mastectomy followed by chemotherapy, radiotherapy, and hormonotherapy regimen. He has been under remission for 4 years until he consulted for respiratory distress. Chest X-ray revealed a large right-sided pleural effusion. He was admitted for a pleural biopsy that concluded in tumor proliferation, leading to pleurodesis. Pathological examination confirmed the breast origin of his pleural effusion.