This rare form of cancer develops in the tissues of the anus. Approximately one in 500 men and women will develop anal cancer during their lifetime, according to the American Cancer Society. The anus, the opening at the end of the rectum through which stool passes, is controlled by muscles.
An estimated 8,590 new cases of anal cancer will be diagnosed in 2020, the majority (5,900) of which will be diagnosed in women. Infection with the sexually transmitted human papillomavirus (HPV) is the catalyst for 95 percent of anal cancers, according to the National Cancer Institute.
Anal cancers are typically treated with surgery, radiation therapy and/or chemotherapy, depending on the stage of the disease.
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