Men who have sex with men are at increased risk for anal human papillomavirus infection and anal intraepithelial neoplasia, according to a meta-analysis published online March 23 in The Lancet Oncology. FRIDAY, March 23 (HealthDay News) -- Men who have sex with men (MSM) are at increased risk for anal human papillomavirus (HPV) infection and anal intraepithelial neoplasia (AIN), according to a meta-analysis published online March 23 in The Lancet Oncology. Dorothy A. Machalek, from the University of New South Wales in Sydney, Australia, and colleagues reviewed data from 53 eligible studies to investigate the prevalence and incidence of anal HPV detection, AIN, and anal cancer in MSM. The researchers found that, in HIV-positive men, there was a pooled prevalence of 35.4 percent for anal HPV-16. The incidence of anal HPV-16 was 13 percent, and clearance occurred in 14.6 percent of men each year, based on data from one estimate. Histological high-grade AIN had a pooled prevalence of 29.1 percent, with two estimates for incidence of 8.5 and 15.4 percent per year. The pooled incidence of anal cancer was 45.9 per 100,000 men. For HIV-negative men, anal HPV-16 had a pooled prevalence of 12.5 percent, with two estimates for incidence of 11.8 and 5.8 percent per year. The pooled prevalence of histological high-grade AIN was 21.5 percent, with two estimates for incidence of 3.3 and 6.0 percent per year. The incidence of anal cancer was 5.1 per 100,000 men. "Anal HPV and anal cancer precursors were very common in MSM," the authors write. "Large, good-quality prospective studies are needed to inform the development of anal cancer screening guidelines for MSM." Several authors disclosed financial ties to pharmaceutical and biotechnology companies, including CSL Biotherapies, which manufactures the HPV vaccine Gardasil. One author has received funding from MSD and GlaxoSmithKline for HPV vaccine research. source:Anal HPV, Cancer Common in Men Having Sex With Men --Doctors Lounge