Prostate cancer metastatic only to the penis.

Prostate cancer metastatic to the penis is rare. We describe a patient who had a painful nodule in the corpora cavernosa during adjuvant radiotherapy after radical prostatectomy for prostate cancer. Biopsy of the nodule revealed a poorly differentiated adenocarcinoma. Immunohistochemical staining for prostate-specific antigen confirmed a prostatic origin for the neoplasm. The lesion to the penis was treated with radiation therapy in conjunction with androgen deprivation therapy. The penile pain completely resolved, and the patient remains alive, 30 months after initiation of therapy.