Anal Cancer

(Cancer of Anus)


Anal cancer is cancer that starts in the anus. It’s a canal at the end of the colon. The sphincter is a muscular ring that allows for bowel movements.

The Anus

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Cancer is when cells in the body split without control or order. These cells go on to form a growth or tumor. The term cancer refers to harmful growths. These growths attack nearby tissues. They also spread to other parts of the body. It’s not clear exactly what causes these problems. It’s likely a mix of genes and the environment.

Anal cancer is linked to human papillomavirus (HPV) infection.

Risk Factors

Your chances of anal cancer are higher for:


You may not notice any symptoms at first. When present, anal cancer may cause:

  • Passing of blood or mucus
  • Pain or pressure
  • Feeling of a mass
  • Itching
  • Change in bowel habits


The doctor will ask about your symptoms and health history. You may also have:

The exam and your test results will help find out the stage of cancer you have. Staging guides your treatment. Anal cancer is staged from 0-4. Stage 0 is a very localized cancer. Stage 4 is a spread to other parts of the body.


Anal cancer is treated with more than one method. Sometimes they’re combined. This may include:


Chemotherapy is the use of drugs to kill cancer cells. It may given by mouth, shots, or IV. The drugs enter the bloodstream and travel throughout the body.

Radiation Therapy

Radiation therapy is the use of radiation to kill cancer cells and shrink tumors. It may be given at the same time as chemotherapy. This may help avoid surgery.

Scar tissue may form in the anus, keeping the anal sphincter from working properly. In addition, damage may occur that results in chronic rectal bleeding.


Local Resection

Local resection allows for the removal of small, localized cancers. A small border of healthy tissue around the cancer will also be removed. Local resection preserves anal function.

Abdominoperineal Resection

An abdominoperineal resection (APR) is a surgery to remove the anus and rectum. It’s an option if the cancer cannot be treated or returns. APR results in the need for a colostomy. A path for solid waste to pass from the body is made through the belly wall. A special bag is needed to collect the waste.


To lower your chances of anal cancer:

  • Talk to your doctor about the HPV vaccine.
  • Practice safe sex to lower your chances of HPV or HIV infection.
  • See your doctor if you have any problems or notice any changes in your anus.


American Cancer Society
United Ostomy Associations of America


Canadian Cancer Society
Ostomy Canada Society


Anal cancer. American Cancer Society website. Available at: Accessed July 26, 2018.
Anal cancer. EBSCO DynaMed Plus website. Available at: . Updated October 30, 2015. Accessed July 26, 2018.
Anal cancer. Merck Manual Professional Version website. Available at: Updated October 2017. Accessed July 26, 2018.
Anal cancer treatment (PDQ)—patient version. National Cancer Institute website. Available at: Updated January 25, 2018. Accessed July 26, 2018.
Joura EA, Leodolter S, Hernandez-Avila M, et al. Efficacy of a quadrivalent prophylactic human papillomavirus (types 6, 11, 16, and 18) L1 virus-like-particle vaccine against high-grade vulval and vaginal lesions: a combined analysis of three randomised clinical trials. Lancet. 2007;369(9574):1693-1702.
Uronis HE, Bendell JC. Anal cancer: an overview. Oncologist. 2007;12(5):524-534.
Last reviewed May 2018 by EBSCO Medical Review Board Mohei Abouzied, MD, FACP
Last Updated: 7/26/2018

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