陰莖異常勃起通常是原因不明的，但是也有因為惡性腫瘤轉移至陰莖海綿體所造成的，而此類病人的預後通常不好。在此提出一個因移形性上皮細胞膀胱癌轉移所造成的陰莖異常勃起病例，並作文獻回顧。

Carcinoma metastatic to the penis is uncommom and usually represents a poor prognosis. The symptoms associated with this condition include dysuria, hematuria, palpable mass, acute urinary retention or priapism. Herein, a case with priapism is presented, the patient proved to have transitional cell carcinoma, originating in the bladder.