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Macmillan and Cancerbackup merged in 2008. Together we provide free, high quality information for people affected by cancer through our publications, website and phone service. Find out more|.
Find out how we produce our information|
This information is about a rare type of cancer called anal cancer.
This is Tania's story of anal cancer. Cancer experiences vary and this video tells just one person’s story. To hear others, visit our online community|.
The anus is the name for the muscular opening at the very end of the large bowel.
It is controlled by a ring of muscle called a sphincter that opens and closes to control bowel movements. The area that connects the anus to the rectum is called the anal canal and is around 3–4cm (1–1½in) long (see diagram below).
Cancer of the anus is rare. Around 930 people are diagnosed with anal cancer each year in the UK.
The most common type of anal cancer is squamous cell carcinoma. Other rarer types are basal cell carcinoma, adenocarcinoma and melanoma. This information is about squamous cell carcinoma.
Diagram showing the position of the anus
View a large copy of the diagram showing the position of the anus|
Anal cancer is slightly more common in women than men. There are a number of factors that can increase your risk of developing anal cancer. These include:
Anal cancer is more likely to develop in people who have had a viral infection called the human papilloma virus (HPV)|. The risk of having HPV increases with the number of sexual partners you have.
People who have anal intercourse are more likely to develop anal cancer. This may be because they are more likely to have anal HPV.
The immune system is part of the body's defence against infections and illnesses like cancer.
Anal cancer is more common in people who have a lowered immunity, such as people taking medicines to suppress their immune system after an organ transplant or people with conditions such as HIV.
Smoking tobacco increases the risk of developing anal cancer. We have more information on stopping smoking|.
However, many people who get anal cancer will not have these risk factors and the cause remains unknown.
The most common symptoms of anal cancer include:
Usually you begin by seeing your GP who will examine you and refer you to a specialist in bowel conditions (gastroenterologist).
At the hospital the doctor will ask you about your general health and any previous medical problems. They will also examine you and take blood samples to check your general health and that your liver is working properly. Before the doctor can make a firm diagnosis of anal cancer a number of tests will have to be done.
This is also sometimes known as a PR examination. A doctor examines your back passage with a gloved finger. Women may also have an internal examination of their vagina, as the vaginal wall is very close to the anal canal.
The doctor will put a thin tube into your back passage to examine the anal canal and rectum. This is called a proctoscopy. A small sample of cells is taken from the tumour to be examined under a microscope (biopsy). This can be done under local or general anaesthetic.
If the tests show that you have anal cancer, you may need further tests to see if the cancer has spread.
These may be taken to show if the cancer has spread.
This uses sound waves to form a picture of the inside of the tummy area (abdomen). The test is painless and takes 15–20 minutes.
Once you are lying comfortably on your back, a gel is spread onto your abdomen. A small device that produces sound waves is then moved over the area. The sound waves produce a picture of the inside of your abdomen.
You may have an endoanal ultrasound scan, which is done with a small probe that is passed into the back passage (rectum). This scan can show the size and extent of the tumour.
A CT scan takes a series of x-rays that build up a three-dimensional picture of the inside of the body. The scan is painless and takes 10–30 minutes. CT scans use small amounts of radiation that are very unlikely to hurt you or anyone you come into contact with. You will be asked not to eat or drink for at least four hours before the scan.
You may be given a drink or injection of a dye that allows particular areas to be seen more clearly. For a few minutes, this may make you feel hot all over. If you are allergic to iodine or have asthma you could have a more serious reaction to the injection, so it is important to let your doctor know beforehand.
This test is similar to a CT scan but uses magnetism, instead of x-rays, to build up a detailed picture of areas of your body. Before the scan you may be asked to complete and sign a checklist. This is to make sure it’s safe for you to have an MRI scan.
Before having the scan, you’ll be asked to remove any metal belongings, including jewellery. Some people are given an injection of dye into a vein in the arm. This is called a contrast medium and can help the images from the scan show up more clearly. During the test you will be asked to lie very still on a couch inside a long cylinder (tube) for about 30 minutes. It is painless but can be slightly uncomfortable, and some people feel a bit claustrophobic during the scan. It’s also noisy, but you’ll be given earplugs or headphones. You'll be able to hear, and speak to, the person operating the scanner.
This is a combination of a PET scan, which uses low-dose radiation to measure the activity of cells in different parts of the body, and a CT scan. PET/CT scans give more detailed information about the part of the body being scanned. They are not always necessary but you can discuss with your doctor whether one would be useful in your case. They are a new type of scan and you may have to travel to a specialist centre to have one.
The stage of a cancer is a term used to describe its size and whether it has spread beyond its original site. Knowing the particular type and the stage of the cancer helps the doctors to decide on the most appropriate treatment.
Cancer can spread in the body, either in the bloodstream or through the lymphatic system. The lymphatic system is part of the body’s defence against infection and disease. It is made up of a network of lymph nodes connected by fine ducts containing lymph fluid. Your doctors will usually check the nearby lymph nodes when staging your cancer.
The cancer only affects the anus and is smaller than 2cm (¾in) in size. It has not begun to spread into the sphincter muscle.
The cancer is bigger than 2cm (¾in) in size, but has not spread into nearby lymph nodes or to other parts of the body.
The cancer has spread to the lymph nodes near the rectum or to nearby organs such as the bladder or vagina.
The cancer has either spread to the lymph nodes in the groin and pelvis, or to the lymph nodes close to the anus, as well as nearby organs such as the bladder or vagina.
The cancer has spread to lymph nodes in the abdomen or to other parts of the body, such as the liver.
A different staging system called the TNM staging system is sometimes used instead of the number system described above.
This system is more complex and can give more precise information about the tumour stage.
If the cancer comes back after initial treatment, it is known as recurrent cancer.
Grading refers to the appearance of cancer cells under a microscope and gives an idea of how quickly a cancer may develop. Low-grade means that the cancer cells look very much like normal cells. They are usually slow-growing and are less likely to spread. In high-grade tumours the cells look very abnormal, are likely to grow more quickly and are more likely to spread.
The National Institute for Health and Clinical Excellence (NICE) recommends that people with an anal cancer are treated by a specialist team. These teams aren't available in all hospitals, so you may have to travel to another hospital for your treatment.
The main type of treatment for anal cancer is a combination of radiotherapy and chemotherapy. The two treatments may be given at the same time (chemoradiation) or in sequence, one treatment following the other. Combined treatment is usually very successful. If radiotherapy and chemotherapy are given at the same time, the side effects can be more severe.
Surgery| may be used to treat small anal tumours or be used in combination with chemotherapy or radiotherapy for advanced anal cancer.
Before you have any treatment, your doctor will give you full information about what it involves and explain its aims to you. They will usually ask you to sign a form saying that you give permission (consent) for the hospital staff to give you the treatment. No medical treatment can be given without your consent.
Treatment can be given for different reasons and the potential benefits will vary for each person. If you have been offered treatment that aims to cure your cancer, deciding whether to have the treatment may not be difficult.
However, if a cure is not possible and the treatment is to control the cancer for a period of time, it may be more difficult to decide whether or not to go ahead.
If you feel that you can't make a decision about treatment immediately, you can ask for more time to decide.
You are free to choose not to have the treatment. You don't have to give a reason but it can be helpful to let the staff know your concerns so that they can give you the best advice.
Radiotherapy| is the use of high-energy rays to destroy cancer cells while doing as little harm as possible to normal cells. Beams are directed at the cancer from outside the body (external radiotherapy) as a series of short, daily treatments using equipment similar to a large x-ray machine.
The treatment is often given for a few minutes each weekday for 4-6 weeks.
During the course of treatment you may have changes in how your bowel works, such as diarrhoea| or passing more wind. These side effects can sometimes be reduced by avoiding particular foods. Your doctor or a dietitian at the hospital can give you advice about this.
Towards the end of your treatment, the skin around the anal area, and possibly the groin area, may become blistered and sore.
Extreme tiredness (fatigue|) is also a common side effect of radiotherapy for anal cancer.
These side effects usually decrease gradually once the treatment has ended but it may take some months for skin changes to go back to normal. A few people find that the way their bowel works is permanently altered.
It's important to discuss any problems with your doctor or specialist nurse, as it is often possible to find ways of reducing them.
Women having radiotherapy for anal cancer may develop vaginal dryness and narrowing of the vagina. Using a vaginal dilator with a lubricating jelly to keep the vaginal walls open and supple can help prevent problems. Your doctor or specialist nurse can give you more information. Some women may also need to use lubricating jelly during sex|.
Infertility| (loss of the ability to have children) can also be a side effect of radiotherapy. If you are concerned about the risk of becoming infertile, it's important to discuss this issue with your specialist before starting treatment.
Chemotherapy| is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. The chemotherapy drugs are usually given by injection into a vein (intravenously). Drugs commonly used to treat anal cancer include mitomycin| and fluorouracil| (5FU).
Chemotherapy can temporarily reduce the number of normal cells in your blood. When your white blood cell count is low you are more likely to get an infection|. If your red blood cell count is low (anaemia) you may tire very quickly; and if the number of platelets is low you may bruise more easily. During chemotherapy your blood will be tested regularly and, if necessary, you may be given antibiotics to treat any infection. You may have blood transfusions| if you become anaemic due to chemotherapy.
Other side effects may include feeling sick (nausea) and being sick (vomiting)|. Some chemotherapy drugs can also make your mouth sore| and cause small mouth ulcers. Regular mouthwashes are important and your nurse will show you how to use these properly.
If you don’t feel like eating meals, you can supplement your diet| with nutritious drinks or soups. A wide variety of drinks are available and you can buy them at most chemists. You can ask your doctor to refer you to a dietitian for advice about your diet.
Surgery| may be used for small tumours. It can also be used if your initial treatment does not completely get rid of the cancer, or if there are signs that your cancer has returned. There are two main types of surgery: local resection and abdominoperineal resection.
This may be used for small tumours on the outside of the anus. This operation only removes the area of the anus containing the cancer cells. The anal sphincter is not usually affected, and so how their bowel works remains the same for most people.
This is the removal of the anus and rectum. This operation requires a permanent colostomy, which involves diverting the open end of the bowel on to the surface of the abdomen (tummy area) to allow faeces to be passed out of the body into a colostomy bag. The opening on the abdominal wall is known as a stoma.
Although the idea of a colostomy is often frightening and distressing at first, most people find that they adapt over time and can return to their normal activities.
You can get support and advice from the stoma nurse in your hospital. Our cancer support specialists| can send you information about having a colostomy.
It's not unusual to have side effects for a time following treatment for anal cancer. These may include feeling bloated, having wind, diarrhoea and occasional incontinence. These side effects can be distressing but are usually temporary and improve over several months.
Your doctor, nurse or a dietitian will be able to give you advice about how to manage any problems you have with side effects.
Having investigations and treatment for cancer can be a very stressful experience.
You may have many emotions| including anxiety, anger and fear. These are all normal reactions and are part of the process that many people go through as they try to come to terms with their condition.
Many people find it helpful to talk things over with their doctor or nurse, or with one of our cancer support specialists. Close friends and family can also offer support.
This section has been compiled using information from a number of reliable sources, including:
For answers, support or just a chat, call the Macmillan Support Line free (Monday to Friday, 9am-8pm)
If you have any questions about cancer, need support or just want someone to talk to, ask Macmillan.