Circumcision Could Reduce HPV-Associated Penile Precancerous Lesions

A new study shows that among Kenyan men, circumcision is associated with a lower prevalence of human papillomavirus (HPV)-associated precancerous lesions of the penis.

Researchers at the University of North Carolina conducted a randomized controlled trial of male circumcision in Kenya, from May 2006 to October 2007, to examine whether male circumcision may reduce HPV-associated precancerous lesions. The study involved 275 men, of which 151 were circumcised and 124 uncircumcised (median age 22 years). The researchers carried out a visual inspection of the penis using a colposcope at the 24-month visit among the participants, with photos read independently by two observers for quality control. Penile exfoliated cells sampled from the glans, coronal sulcus, and shaft were tested for HPV DNA using a real time polymerase chain reaction (PCR) assay to measure viral loads.

The results showed that circumcised men had a substantially lower prevalence of flat penile lesions (0.7%) compared to uncircumcised men (26.0%). Additionally, compared to men who were HPV negative, men who were HPV DNA positive or who had high HPV16/18/31 viral load had higher odds of flat penile lesions. Among men with flat penile lesions, HPV56 (29%) and HPV16 (25.8%) were the most common types within single or multiple infections. The study was published in the August 2011 issue of the International Journal of Cancer.

“Interventions that reduce HPV-associated penile lesions could be important to both men and women, because such lesions may increase HPV transmission from men to their sexual partners,” said lead author Jennifer Smith, PhD, of the department of epidemiology. “Circumcision may also provide a useful intervention to prevent HPV-associated penile lesions and ultimately invasive cervical cancers in less developed countries, since prophylactic HPV vaccines may not be readily available to men, and current HPV vaccines do not include protection against all high-risk HPV types.”

HPV is a sexually transmitted virus that plays an important role in genital cancers in men and women, including cancers of the penis and cervix. While the majority of the nearly 200 known types of HPV cause no symptoms in most people, some types can cause warts (verrucae), while others can lead to cancers of the cervix, vulva, vagina, and anus in women or cancers of the anus and penis in men. Flat penile lesions are much more frequent in uncircumcised men and associated with higher prevalence of HPV and higher viral loads.

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