The exact cause of most penile cancer is unknown. While many men who develop penile cancer have no known risk factors, it may be associated with the following:
- Human papillomarvirus (HPV) infection: This type of infection is considered the most important avoidable risk factor for penile cancer because the virus can cause warts which are passed along during sexual contact
- Having unprotected sexual relations with multiple partners, which increases risk of contracting HPV
- Smoking: Smoking is thought to damage the DNA of cells in the penis and contribute to the development of penile cancer, especially in men with HPV infection
- Psoriasis treatment in men: Men who have been treated for psoriasis with a of a drug called psoralen and exposure to ultraviolet light have a higher rate of penile cancer.
- Poor hygiene: Oily secretions from the skin and dead skin cells, which accumulate under the foreskin, can result in a substance called smegma. While not proven, it has been suggested that smegma may contain cancer-causing substances.
It had been believed that men who are circumcised have a lower risk of developing penile cancer, however, this has not been proven.
Early symptoms of penile cancer include the appearance of a painless nodule, a warty growth or ulcer on the penis, especially on the glans or foreskin, or swelling at the end of the penis. Any abnormality of the penis, including warts, blisters, sores, ulcers, white patches, rash or bumps, should be evaluated by a physician. Most penile cancers do not cause pain, but can cause ulceration and bleeding in later stages. A number of benign conditions, such as genital warts or infections, can have similar symptoms, but it is important to discuss these with a physician promptly since penile cancer detected and treated in early stages can be curable.