Anal cancer is a disease in which malignant (cancer) cells form in the tissues of the anus.
The anus is the end of the large intestine, below the rectum, through which stool (solid waste) leaves the body. The anus is formed partly from the outer, skin layers of the body and partly from the intestine. Two ring-like muscles, called sphincter muscles, open and close the anal opening to let stool pass out of the body. The anal canal, the part of the anus between the rectum and the anal opening, is about 1½ inches long.
The skin around the outside of the anus is called the perianal area. Tumors in this area are skin tumors, not anal cancer.
Anal Cancer
Many types of tumors can develop in the anus. Some of these tumors are benign (noncancerous). Others are cancerous, which means they can penetrate into surrounding tissues and can spread to other parts of the body. There are also some growths that start off benign but can develop into anal cancer. These are called precancerous conditions.
Risk factors of developing anal cancer
Being infected with the human papillomavirus (HPV) can affect the risk of developing anal cancer. Risk factors of developing anal cancer include:
- Being over 50 years old.
- Being infected with human papillomavirus (HPV).
- Having many sexual partners.
- Having receptive anal intercourse (anal sex).
- Frequent anal redness, swelling, and soreness.
- Having anal fistulas (abnormal openings).
- Smoking cigarettes.
Signs and Symptoms of anal cancer
Possible signs of anal cancer include bleeding from the anus or rectum or a lump near the anus. These and other symptoms may be caused by anal cancer. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:
- Bleeding from the anus or rectum.
- Pain or pressure in the area around the anus.
- Itching or discharge from the anus.
- A lump near the anus.
- A change in bowel habits.
