|| Checking for direct PDF access through Ovid
Human papillomavirus types 6 and 11 (HPV-6 and -11) cause greater than 90% of genital warts in males and females. Data show that approximately 3 to 4 million cases of genital warts in men occur each year, with a peak rate of 500 per 100,000 in the 25- to 29-year-old group . Most of these genital warts are diagnosed in men younger than 30 years. In addition to genital warts, men are at risk for several HPV-related morbidities including penile, anal, and oral cancers.As in women, HPV is associated with anogenital cancers in men, specifically of the anus and penis. Approximately 90% of anal cancers are associated with HPV, and of those with HPV, 90% are due to HPV 16 and 18 . This is higher than seen for cervical cancers, of which ∼70% are due to HPV-16 and -18. Although women have higher rates of anal cancer than men in the general population, HIV-infected men who have sex with men (MSM) are at greatest risk [3-5]. The age-adjusted incidence rate of anal cancer in women in the United States is ∼1.4 per 100,000 and that in men is ∼1.0 per 100,000. The estimated annual incidence for HIV infected MSM is between 25 and 100 per 100,000 [6-8]. In comparison, age adjustable rates of cervical cancer is 8.1 per 100,000. The incidence of anal cancer is also rising in both men and women in the general population, with an estimated 1,600 new cases of anal cancer occurring each year in women and 900 cases in men . The reasons for this change are unknown. The association with HIV and other HPV-associated cancers underscores the importance of the immune response in controlling HPV.As with vulvar cancer, the association between penile cancers and HPV varies considerably by histology. Almost 100% of basaloid and warty penile cancers are associated with oncogenic HPV types, whereas only 30% to 40% of verrucous and keratinizing squamous cell cancers are associated with HPV . Human papillomavirus type 16 is the predominant type found in HPV-associated tumors. Penile cancers are relatively rare in the United States, with an annual incidence of approximately 1 per 100,000. Hispanics have the highest incidence with 1.3 per 100,000, and Asian Pacific Islanders have the lowest with.4 per 100,000. Penile cancers represent only 0.4% to 0.6% of all male cancers in the United States and Europe. The incidence is almost 20-fold in South American, African, and Asian men. In Brazil, the incidence is 3 per 100,000. In Uganda, 1% of men will develop penile cancer. Although the exact reasons for the variation in incidence are not elucidated, circumcision is protective against penile cancer and likely plays a large role . Other risks for penile cancer include smoking, high-risk sexual activity, and phimosis. These risks may vary by histology, but few studies have examined risk by subtypes . One study found that a reported history of priapism was also associated with penile cancer [13, 14]. Like cervical cancer, penile cancer under the age of 20 is extremely rare with a mean age of 63 to 67 years . In addition to anogenital cancers, HPV is associated with oropharyngeal cancers in both men and women . Overall, HPV is associated with approximately 25% of head and neck cancers. The tonsil and the base of the tongue are the most common sites of HPV-associated cancers in the oral cavity, with approximately 50% being associated with HPV. Among whites and blacks, 5.1 and 6.