Diversity of HPV types in the male genital region

Abstract

HPV is mainly transmitted by sexual contact and infection by these viruses are strongly associated to the development of cancer from the cervix, vulva and anus in women, penis and anal cancer in men, and head and neck cancer in both genders. Case-control studies conducted in women with cervical cancer showed that male partner sexual behavior influences the risk of women of developing this neoplasia. However little is known about the natural history of penile HPV infection in men. Since 2005 a prospective international (Brazil, Mexico, United States) study in men is being conducted, the HPV in Men Study (HIM) in which about 4.000 men are being followed every 6 months for a period of 4 years. For the genotyping of these samples, a methodology capable of identifying 37 HPV types commonly detected among women genital specimens is being used. Initial analysis of the HIM study included 1.160 men enrolled from March 2005 to December 2006. In this group HPV genital prevalence was 65,2%, of which 14,7% comprised non classified infections. Along this cohort study 1.000 specimens of unclassified HPV were identified. In order to better understand the significance of these viral types in the natural history of HPV infection, it is crucial to characterize these samples. Our aim is: (1) Identify HPV types infecting samples from the HIM study characterized as unclassified; (2) Determine the frequency of individual HPV types detected among these specimens; and (3) Identify factors independently associated with the acquisition, persistence and clearance of these HPV types in men. (AU)