Gynecomastia with rare granulomatous lobular mastitis: a case report and literature review

This study was performed to describe a rare case of granulomatous lobular mastitis (GLM) that was successfully treated with bromocriptine in a male patient with gynecomastia and hyperprolactinemia. A 20-year-old man presented with a 1-year history of breast enlargement and galactorrhea. Physical examination revealed bilateral breast enlargement, porous discharge, and a 3-cm left breast lump in the 10-o’clock quadrant. Magnetic resonance imaging of the brain showed a 1.2-mm pituitary tumor. Laboratory analysis revealed hyperprolactinemia with low serum testosterone and elevated prolactin and estradiol levels. The lump in the left breast was examined by ultrasonography and mammography, and a core needle biopsy revealed chronic inflammation. The patient’s galactorrhea and breast lump disappeared after 3 months of treatment with bromocriptine at 2.5 mg once a day. His serum prolactin level also normalized. Following a review of this case, the patient was diagnosed with gynecomastia with hyperprolactinemia complicated by rare GLM. To the best of our knowledge, this is the first reported case of concurrent gynecomastia and GLM.