Primary apocrine adenocarcinoma of scrotum suspected as urothelial carcinoma metastasis: A clinical and pathological dilemma

A 78-year-old man presented with an enlarging, tender mass in the scrotum separate to the testes. This was on the background of radical cystoprostatectomy, urethrectomy, and ileal conduit formation for high-grade urothelial carcinoma of the bladder invading submucosa 3 years prior. Examination revealed a 4 × 5 cm lesion, which was hard, fixed to the overlying skin and nodular to palpation. Ultrasound confirmed a solid mass in the scrotum extending into the perineum. Computerized tomography of the chest, abdomen, and pelvis revealed enlargement of inguinal lymph nodes but no other metastases. Complete resection of the scrotal lesion and selective removal of regional lymph nodes was performed. Rather than a cutaneous scrotal metastasis from the bladder urothelial carcinoma, histological examination suggested a primary apocrine adenocarcinoma of the scrotum. This case report explores the clinical and pathological features associated with both of these unusual differential diagnoses.