Rare β-human chorionic gonadotrophin-secreting urothelial carcinoma initially presenting as gynecomastia

Gynecomastia is a relatively common condition arising from disproportionate concentrations of estrogen and androgen. Most cases of bilateral gynecomastia in men are idiopathic or drug-induced but can rarely arise secondary to malignancy. We present the case of a 57-year-old male who presented with new-onset gynecomastia and recurrent episodes of hematuria. Laboratory testing revealed elevated estradiol, free testosterone, and β-human chorionic gonadotropin (β-hCG) with suppressed luteinizing hormone (LH) and follicle stimulating hormone (FSH), concerning for ectopic β-hCG secretion. Mammography, breast and testicular ultrasonography, and chest computed tomography demonstrated no evidence of breast, testicular, or lung malignancy. Concurrent evaluation of hematuria with cystoscopy identified a 6-cm tumor on the posterior bladder wall. The patient underwent transurethral resection of the bladder tumor and was diagnosed with papillary high-grade T1 urothelial carcinoma. The β-hCG immunohistochemical staining of the tumor was positive, and the patient's β-hCG level was undetectable 1 month postoperatively. A review of the literature revealed there are only a few reports detailing urothelial carcinomas capable of secreting β-hCG. To the best of our knowledge, this is the first case of a β-hCG-secreting papillary T1 urothelial carcinoma initially presenting as gynecomastia.