Age: Most cases of anal cancer occur in people over the age of 50 years Human papillomavirus (HPV): Infection with the Human Papillomavirus (HPV). Patients with a weakened immune system caused by HIV or an organ transplant. History of cancer: Those who have had cervical, vulvar or vaginal cancer have an increased risk of anal cancer. Promiscuity – People who have many sexual partners over their lifetime have a greater risk of anal cancer. Anal Sex: People who engage in receptive anal sex have an increased risk of anal cancer. Smoking: Smoking cigarettes may increase your risk of anal cancer.
