Human papillomavirus (HPV) is the most common and cancer of the penis in men. Most HPV-associated sexually transmitted virus in the United States. More than lesions can be diagnosed by microscopic examination of 40 HPV types are known to infect the urogenital and anal smears or biopsies. In difficult cases, ancillary techniques regions of men and women, targeting the stratified squa-such as in situ hybridization can help to confirm the diagnosis mous epithelium of the perineal skin or mucous mem-(Fig. F23.6.1). Recently, two vaccines (Cervarix and Garbranes. Most women will be infected by HPV in their dasil) have become available to protect women against the lifetime, but only a small percentage (5%–10%) will de-types of HPV that cause most cervical cancers. Cervarix is velop a persistent infection and the associated risk of cer-designed to prevent infections from HPV types 16 and 18 vical cancer. Of the approximately 40 sexually transmitted and contains recombinant noninfectious viruslike particles HPV types, most (90%) cause genital warts rather than (VLPs) from both virus types. Gardasil contains a mixture of cervical cancer and so are called low-risk HPV types (e.g., recombinant VLPs from HPV types 6, 11, 16, and 18. Nei-HPV types 6 and 11). Low-risk HPV types tend to infect ther vaccine is therapeutic (i.e., they do not clear prior in-mature epithelial cells and lead to genital warts or mild fection), but both lead to the development of specific cervical dysplasia. HPV types 16 and 18 are the most immunity against HPV infections. The vaccines are most efcommon high-risk HPV types and are associated with 70% fective for girls and young women between ages 9 and 26 of cervical cancers. High-risk HPV types usually infect di-who have had no prior HPV exposure and who complete viding cells, cause moderate to severe cervical dysplasia or the three-injection immunization protocol before initiation carcinomas, and are linked to anal cancer, vulvar cancer, of sexual activity.
 FOLDER 23.6 Clinical Correlation: Cervix and Human Papillomavirus (HPV) Infections (Cont.)
FIGURE F23.6.1 • Photomicrograph of in situ hybridization of a human cervical biopsy showing HPV infection. a. This low-magnification photomicrograph shows stratified squamous epithelium of the cervix hybridized with DNA probes to HPV types 6 and 11 and counterstained with nuclear fast red. Note that the majority of infected cells are mature cells located in the upper layers of the stratified squamous epithelium of the ectocervix. 120. b. This higher-magnification photomicrograph shows viral particles stained purple within the nuclei of infected cells. 225. (Courtesy of Dr. Fabiola Medeiros, Mayo Clinic.)