Colloid adenocarcinoma of the urethra associated with mucosal in situ carcinoma

Adenocarcinoma is a rarity among the primary urethral carcinomas. It usually exhibits a papillary or glandular pattern and is often believed to arise from the mucosal glands. We report a unique case showing the histologic features of colloid adenocarcinoma that appears to have evolved from carcinoma in situ of the urethral epithelium.