Anal Cancer

What is anal cancer?

Anal cancer is a rare type of cancer that occurs in the anal canal, a short tube at the end of the rectum through which stool leaves the body. The disease occurs when cancer cells form in the tissues of the anus. Anal cancer is more likely to affect people age 60 or older. Another major risk is infection with HPV (human papillomavirus). Other things that may increase one’s risk of getting anal cancer include: having a history of cervical, vulvar or vaginal cancer, having many sexual partners, engaging in anal sex, smoking cigarettes, and taking drugs that suppress the immune system.

What are the symptoms of anal cancer?

Common symptoms of anal cancer include the following:

• Rectal bleeding
• Anal pain
• A mass or growth in the anal canal
• Anal itching
• A change in bowel habits

What causes anal cancer?

Anal cancer forms when a genetic mutation turns normal cells into abnormal cells. Healthy cells grow at a steady rate, and die at a set time. Abnormal cells, however, grow and multiply at an out of control rate, and they take much longer to die. This leads to an accumulation of the bad cells, which forms a tumor. Cancer cells can also invade nearby tissue and spread through other body parts, but this is rare in most anal cancer cases.

How is anal cancer diagnosed?

Anal cancer is diagnosed using the following procedures:

• Physical examination of the anal canal and rectum for abnormalities
• Recording of patient’s medical history
• Anoscopy
• Ultrasound
• Biopsy

After diagnosis, various imaging tests (CT scans, MRIs, X-rays) are used to find out if the cancer cells have spread to other parts of the body. This is called staging.

What are the stages of anal cancer?

Doctors use the information obtained during diagnosis to assign a patient’s cancer a stage. Anal cancer stages are:

• Stage I: Cancer is 2 cm or less in size
• Stage II: Cancer is larger than 2 cm, but has not spread to other areas of the body
• Stage IIIA: Cancer is any size and has spread to either nearby lymph nodes or other areas close by
• Stage IIIB: Cancer is any size and has spread to nearby areas and lymph nodes, or other lymph nodes in the pelvis
• Stage IV: Cancer is any size and has spread to body parts away from the pelvis

What are the treatments for anal cancer?

Anal cancer treatment depends on the stage of the cancer, the location of the tumor in the anus, and the patient’s overall health and preferences. It includes:

• Chemotherapy
• Radiation therapy
• Surgery
• Supportive care focused on pain relief

Where can I find out more about anal cancer?

• American Cancer Society
• Mayo Clinic
• National Cancer Institute