Diagnosis: Secondary tumors involving the penis
• In spite of the rich vascularity of the penis, it is a rare site for metastatic carcinoma.
• All of the carcinomas listed have been reported to metastasize to the penis; however, genitourinary tumors, particularly of prostatic and urinary bladder origin, are the most common primary site for tumors metastasizing to the penis.
• In the penis, most metastases are within the vascular channels of the erectile tissues of the penis. This is usually manifested as multiple painless subcutaneous nodules. Rarely, malignant priapism can occur.
• The distinction between metastatic urothelial carcinoma of the urinary bladder and primary penile urethral carcinoma can be difficult. Demonstration of in situ urothelial carcinoma at the site in the penile urethra can be a helpful clue that it is a primary carcinoma.