This page was reviewed under our medical and editorial policy by Maurie Markman, MD, President, Medicine & Science
This page was updated on July 20, 2022.
Anal cancer is a rare disease that forms in the tissues of the anus, the opening at the end of the rectum (where the large intestine ends), which is connected to the outside of the body and through which stool passes. About one in 500 men and women will develop anal cancer in his or her lifetime, according to the American Cancer Society (ACS).
This cancer type has various forms, and incidence rates of the disease are on the rise. Women are at a slightly greater risk than men for developing anal cancer, which is found mostly in older adults. The catalyst for more than 90 percent of anal cancers is infection with the human papillomavirus (HPV) from a sexual partner, according to the National Cancer Institute.
At City of Hope, our medical experts are trained and experienced in diagnosing and staging anal cancer. In order to diagnose the type and stage of your disease, our doctors may choose from a number of diagnostic tools, including a biopsy, CT scan, digital rectal exam or lab tests. We will then use that information to recommend a comprehensive treatment plan, explaining your options so you can make an informed decision about your care. To help support your quality of life, we will also help you manage pain or discomfort caused by the cancer, as well as nausea, neuropathy or other side effects that may result from treatment.
This overview will cover the basic facts about anal cancer, including:
If you believe you may be experiencing symptoms of anal cancer and want to schedule an appointment for diagnostic testing, or if you’re interested in a second opinion on your anal cancer diagnosis and treatment plan, call us or chat online with a member of our team.
Known risk factors for anal cancer include chronic infection with HPV, gender and age. HPV infection spreads primarily through vaginal, oral or anal sex. The HPV vaccine provides protection against strains of the virus.
Other common risk factors for anal cancer include:
Two-thirds of anal cancer cases occur in people older than 55. The average age for diagnosis is in the early 60s, according to the ACS. Women are at greater risk than men.
Smokers have a higher risk of anal cancer, but that risk decreases significantly when they quit. Anal cancer is more prevalent among African Americans than in whites.
"I believe I have a strong desire and will to live. Going through cancer treatment changed me for the better. It gave me a new perspective on life. I have made lifestyle changes, and my outlook on the future is optimistic."
The forms of abnormal cell growth in the anus are anal intraepithelial neoplasia (AIN) or anal squamous intraepithelial lesions (SILs). Tumors in or on the anus may be benign tumors (noncancerous) or malignant tumors (cancerous).
The different types of anal cancer, and where they show up, include:
Squamous cell carcinoma is the most common type of anal cancer. Carcinoma in situ, also called high-grade squamous intraepithelial lesions or Bowen disease, refers to precancerous cells found on the inner surface of the anus.
Early detection of anal cancer is common. The first indication of anal cancer is often rectal bleeding, which occurs in more than half the patients. Symptoms of anal tumors are often similar to benign conditions, such as hemorrhoids, anal fissures, fistulas and anal warts, so it’s important to discuss your symptoms with your doctor.
Besides rectal bleeding, symptoms of anal cancer may include:
Our pathologists perform a comprehensive physical exam and conduct a series of tests to diagnose anal cancer.
Those tests for diagnosing anal cancer may include:
According to the ACS, the five-year survival rate for anal cancer ranges from 34 percent for cancer that has spread to distant parts of the body to 82 percent for cancer that has not spread beyond the anal area.
In the past, surgery was the only treatment for anal cancer patients. Treatment options today often involve a combination of radiation therapy and chemotherapy.
Two types of surgical procedures may be used in anal cancer treatment:
Surgery to treat anal cancer may involve a permanent colostomy, which requires a bag attached to the abdomen to collect stool. The bag sits outside the body and connects to the end of the large intestine, through a permanent opening in the abdomen called a stoma.
Your multidisciplinary care team will work with you to customize a comprehensive treatment plan that fits your treatment goals and individual needs. Your tailored plan will include evidence-based treatments designed to attack the cancer, as well as supportive care services that are designed to help you manage side effects. This supportive approach to cancer care helps anal cancer patients better tolerate treatment so they can reduce delays and get the most out of life.
Pain is one of the most common side effects anal cancer patients experience. That’s why your care team will include a pain management physician, who may recommend narcotic pain relievers, or may interventional procedures like nerve blocks that numb the pain around the tumor or pain pumps that release concentrated pain medication on the spine. Your care team may also recommend naturopathic support, which focuses on using natural, non-toxic techniques to support the body’s healing process.
Because your care team works all under one roof, you have access to a team of doctors, providers and support staff who can tailor treatments and supportive therapies to your needs, all in real time.
Supportive care therapies that may be recommended to help patients with anal cancer stay strong and maintain their quality of life include:
