Aug. 24, 2009 -- Preventing sexually transmitted HPV infections may reduce a man's risk of developing cancer of the penis. A worldwide review of studies has found that one of the most common types of the human papillomavirus (HPV) is linked to about half of all penile cancers.
HPV refers to a group of more than 100 different virus types, some of which are sexually transmitted. Some types are considered "high risk" because they make a person more likely to develop certain diseases, such as cancer. For example, HPV-16 and HPV-18 are associated with about 70% of cervical cancers in women.
Now, researchers say HPV-16 is the leading HPV type liked to penile cancer; HPV-18 is the second most common type, according to a report in the Journal of Clinical Pathology. Two cancers of the penis (basaloid and warty squamous cell carcinomas) were most often associated with the two high-risk HPV types.
The findings are based on a review of 31 major penile cancer studies published between 1986 and June 2008. Prevalence of HPV infection was 46.9% among the 1,466 penile cancers identified. A larger international study is under way to better examine the prevalence and causes of penile cancer.
Penile cancer is rare. According to the American Cancer Society, it occurs in about one in 100,000 men in the U.S. The cancer is more common in some parts of South America and Africa. There are 26,300 new worldwide cases of penile cancer every year.
Factors that can raise a man's risk for penile cancer include poor hygiene, smoking, and not being circumcised or having unretractable foreskin on the penis. Proper use of condoms during sexual activity can lower one's risk for HPV infection. However, condoms do not completely protect against HPV because the virus may be found on other parts of the body, such as the anal area.
The study's authors say about 7,000 cases of penile cancer could be prevented each year if such infections could be wiped out. A vaccine called Gardasil is available in the U.S. to protect girls and women against certain HPV infections. It is not approved for men.