Anal cancer

If you or someone you know has been diagnosed with anal cancer, we can provide the information you need, from understanding the cancer itself, to choosing the right treatment, to finding support.

Anal cancer is different from bowel cancer (also known as colon or rectal cancer). If you're not sure what the difference is or how it affects you, you can call our helpline.

What you should know about anal cancer

  • Anal cancer is a change in the cells in the anal canal, which affects how the anus works normally.
  • The cause of anal cancer is unknown. Your risk of developing it increases if you are male, smoke, infected with HPV or HIV, have anal sex and lowered immunity.
  • The main symptoms of anal cancer are bleeding from your back passage, small lumps around your anus, pain or discomfort in the anal area, anal itchiness, and an abnormal discharge and losing regular control of your bowel.
  • Anal cancer is usually diagnosed by a rectal exam and a proctoscopy or sigmoidoscopy.
  • Treatment for anal cancer can include radiotherapy and chemotherapy (often given together) and surgery.

What is the anus?

Your anus or anal canal is found at the end of your large bowel, which opens to the outside of your body. When you pass a bowel motion, stools pass through your anus. Your anus is controlled by a ring of muscle called the sphincter. This opens and closes to allow stools to pass from your body.

The Digestive System

What is anal cancer?

Anal cancer occurs when cells in the anal canal change and start to grow abnormally. They can eventually form a large mass of cells called a tumour. If the tumour is not treated, it can affect how your anus works normally.

How common is anal cancer?

Anal cancer is a rare cancer. It can occur in both men and women. In 2017 it was estimated that 55 people in Ireland are diagnosed with anal cancer each year.

Cancer publications

For booklets and factsheets, including information about cancer types, treatments, side-effects, emotional effects, financial information and more. Visit our publications section.