Anal infection with the human papillomavirus (HPV) that results in genital warts is a major risk factor for cancer. Immunocompromised patients, such as those with HIV, are prone to anal cancer. In this subgroup, the prognosis is worse than in non-immunocompromised patients.
Gardasil, one of the HPV vaccines originally approved for the prevention of cervical cancer, is also approved for the prevention of anal cancer in men and women.
Anal cancer is a rare malignancy that begins in the anus, the opening at the end of the rectum. The American Cancer Society estimates that 7,210 cases of anal cancer will be diagnosed in 2014 and about 950 deaths will occur that year from anal cancer.
About half of all anal cancers are diagnosed before the malignancy has spread beyond the primary site, while 13% to 25% are diagnosed after the cancer has spread to the lymph nodes and 10% O it has metastasized. When found early, anal cancer is highly treatable.
The overall five-year survival rate after anal cancer diagnosis is 60% for men and 71% for women. When cancer is diagnosed in its earliest stage, the 5-year survival rate is 82%. Once the cancer has spread to the surrounding lymph nodes, the 5-year survival drops to 60%. If the cancer has spread to distant organs, about one in five patients lives for five years or more. Most anal cancers (80%) are diagnosed in people over 60 years of age. Before age 35, anal cancer is more common in men. However, after age 50, anal cancer is slightly more common in women.
The incidence rate of anal cancer is six times higher in single men compared to married men. The anal intercourse receptive is strongly related to the development of anal cancer.
