[Anal cancer and human papillomaviruses: a perspective based on the cervical cancer model]

Anal cancer is a rare pathology in the general population but the incidence of this cancer has been on the rise for certain high-risk groups, such as homosexual men and immunodepressed subjects. The incidence of anal cancer is 10 times higher in the HIV-positive population than in the female population in general. Moderate to severe dysplasias (AIN2-3) are types of precancerous lesions that usually precede the appearance of the cancer. HPV16 infection is the most common (3/4 of the cases) followed by HPV18 (less than 10%). In anal cancer, HPV16 is present in over 75% of the cases. The prevalence of HPV in anal cancer is higher in women (90%) than in men (75%). Squamous cervical and anal cancers have strong similarities founded on the causal association to HPV, in particular HPV16. Recent data indicate that anti-HPV vaccination has a significant potential in preventing HPV infections, precancerous lesions, and anal cancer in the general population as well as in the high-risk groups.