IMPORTANT NEW STUDY:
CIRCUMCISION NOT LINKED TO RISK OF NEW HPV INFECTIONS, BUT CIRCUMCISED MEN MAY HAVE REDUCED ABILITY TO CLEAR CANCER-ASSOCIATED HPV16 INFECTIONS

New well-designed cohort study from Brazil, Mexico and the United States with more than 4000 participants pulls one of the American Academy of Pediatrics' (AAP) most promoted health claims apart. Overall, during follow-up there was no difference in rates of new HPV infections between circumcised and intact men in the study.

HPV is the group of sexually transmitted agents (human papillomaviruses) that cause both anogenital warts (aka condyloma) and neoplastic lesions and cancers of both male and female genitalia, the anus and the tonsils.

Two types of HPV, known as HPV6 and HPV16 are responsible for the majority of all HPV-associated lesions, including genital warts (HPV6) and cancers (HPV16). While the overall findings of this study were negative, meaning that it found no overall differences between circumcised and intact men, among the few type-specific differences that were actually found, was a significantly reduced ability among circumcised men to clear their newly acquired HPV6 and HPV16 infections. This is particularly worrisome, because it is well-established that persistent HPV16 infection is the initial step on the path from HPV acquisition to cancer.

With this study, one of Brian J. Morris' and the AAP's most cherished arguments in favor of circumcision falls apart. Notably in industrialized parts of the world where the burden of heterosexually acquired HIV/AIDS - the main health problem circumcision is postulated to reduce - is low.

The paper must be even more disturbing to the pro-circumcision lobby, because two of its authors, Xavier Castellsague and Francois Xavier Bosch, are prominent co-authors of several prior papers suggesting a protective effect of circumcision against HPV infection, including the 2002 landmark study in the acclaimed New England Journal of Medicine, whose findings are now seriously undermined by their new and methodologically stronger study (nejm.org/doi/full/10.1056/NEJMoa011688).

It seems there may soon be one pro-circumcision myth less to fight.