Anal cancer occurs in the anus, located at the end of the gastrointestinal tract. It is different from and less common than colorectal cancer, which is cancer of the colon or rectum.
Anal cancer is rare, but the number of new cases is rising. According to the American Cancer Society, in 2017, there are likely to be about 8,200 new cases, of which 5,250 will affect women and 2,950 will affect men. Around 1,100 people are expected to die from anal cancer, including 650 women and 450 men.
Various risk factors are linked to anal cancer, but infection with two types of the human papilloma virus (HPV) appear to underlie 79 percent of cases.
Anal cancer is rare before the age of 35 years. The average age of diagnosis is in the early 60s. Men have a 1-in-500 chance of getting anal cancer, and the risk is slightly higher in women.
Symptoms and signs
Common symptoms of anal cancer may include
rectal bleeding noticeable if there is blood on feces or toilet paper
pain in the anal area
lumps around the anus, which may be mistaken for piles, or hemorrhoids
mucus or jelly-like discharge from the anus
changes in bowel movements, including diarrhea, constipation, or thinning of stools
fecal incontinence, or problems controlling bowel movements
women may experience lower back pain as the tumor presses on the vagina
women may experience vaginal dryness
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Treatment for anal cancer will depend on various factors, including how big the tumor is, whether or not it has spread, where it is, and the general health of the patient. Surgery, chemotherapy, and radiation therapy are the main options.
The type of surgery depends on the size and position of the tumor.
The surgeon removes a small tumor and some surrounding tissue. This can only be done if the anal sphincter is not affected. After this procedure, the person will still be able to pass a bowel movement.
The anus, rectum and a section of the bowel are surgically removed, and a colostomy will be established. In a colostomy, the end of the bowel is brought out to the surface of the abdomen. A bag is placed over the stoma, or the opening. The bag collects the stools outside the body. A person with a colostomy can lead a normal life, play sports, and be sexually active.
Chemotherapy and radiotherapy
Most patients will probably need chemotherapy, radiation therapy, or both.