Anal Cancer
Condition
(Cancer of Anus)
Definition
Anal cancer is cancer that starts in the anus. The anus a canal at the end of the colon. Stool (poop) is passed through it.
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Causes
Cancer is when cells in the body split without control or order. These cells go on to form a growth or tumor. Cancer refers to harmful growths. These growths attack nearby tissues and can spread to other parts of the body.
Most anal cancer is linked to a human papillomavirus (HPV) infection. The exact cause is not always known. It may be related to genes and the environment.
Risk Factors
Things that raise the risk of anal cancer are:
- Anal intraepithelial neoplasia—precancerous changes in cells
- HIV infection
- Having many sex partners
- Receiving anal sex
- Smoking
- Genital warts
- Immune system problems from certain medicines
- Cervical dysplasia or cervical cancer
Symptoms
Anal cancer may have no symptoms at first. When present, symptoms may be:
- Passing of blood or mucus
- Pain or pressure
- Feeling of a mass
- Itching
- A change in bowel habits
Diagnosis
The doctor will ask about symptoms and past health. A rectal exam will probably be done. The doctor will put a gloved finger in the rectum to feel for changes. If the doctor suspects a problem, tests may be done, such as:
- Blood tests
- Anoscopy—a scope to see inside the rectum and anus
- Sigmoidoscopy—a long tube inserted to see the anus, rectum and lower large intestine
- Biopsy —a sample of anal tissue is tested for cancer in a lab
The exam and test results will help find the stage of the cancer. Anal cancer is staged from 0 to 4. Stage 0 is a very localized cancer. Stage 4 has spread to other parts of the body.
Treatment
Treatment is based on the location, type, and stage of the cancer. Anal cancer is treated with more than one method.
Chemotherapy (chemo) uses drugs by mouth, shots, or IV to kill cancer cells. It may be given:
- With radiation
- Instead of surgery
- Before or after surgery
- For advanced cancer—to help control the cancer and ease symptoms
Radiation therapy is the use of radiation to kill cancer cells and shrink tumors.
- Local resection—to remove small, localized cancers. A small border of healthy tissue around the cancer will also be removed. Local resection keeps anal function.
- An abdominoperineal resection (APR)—to remove the anus and rectum. It is 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.
Prevention
To lower the risk of anal cancer:
- Talk to the doctor about the HPV vaccine .
- Practice safe sex to lower the risk of HPV or HIV infection.
- See the doctor for any problems or changes in the anus.
American Cancer Society
United Ostomy Associations of America
CANADIAN RESOURCES:
Canadian Cancer Society
Ostomy Canada Society
American Cancer Society
United Ostomy Associations of America
CANADIAN RESOURCES:
Canadian Cancer Society
Ostomy Canada Society
References
- Anal cancer. American Cancer Society website. Available at: https://www.cancer.org/cancer/anal-cancer.html.
- Anal cancer. EBSCO DynaMed website. Available at:https://www.dynamed.com/condition/anal-cancer-5.
- Anal cancer treatment (PDQ)—patient version. National Cancer Institute website. Available at: https://www.cancer.gov/types/anal/patient/anal-treatment-pdq.
- Symer MM, Yeo HL. Recent advances in the management of anal cancer. F1000Res. 2018;7:F1000 Faculty Rev-1572.
Contributors
- Mohei Abouzied, MD, FACP
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