Anal cancer

Your health expert: Dr Sarah Smith, Consultant in Clinical Oncology
Content editor review by Sheila Pinion, June 2024
Next review due June 2027

Anal cancer is a type of cancer that starts in your anus, which is the opening at the end of your large bowel (large intestine). Anal cancer happens when cells in your anus start growing in an uncontrolled way. This abnormal growth causes symptoms such as pain and bleeding from your bottom.

About anal cancer

Anal cancer is rare – about 1,500 people are diagnosed with it each year in the UK. But over the past 20 years, it’s become more common, especially in women.

Although your anus is part of your large bowel, anal cancer is different from bowel cancer (colorectal cancer). Bowel cancer starts in your large bowel (colon) or back passage (rectum).

Types of anal cancer

There are different types of anal cancer, depending on the type of cell the cancer starts in. Types of anal cancer include the following.

Squamous cell carcinoma. This is the most common type – around 90 per cent of anal cancers are squamous cell carcinomas. It develops in the squamous cells that line your anal canal and the cells of your anal margin. Your anal canal is the tube that connects the lower part of your large bowel (rectum) to the outside of your body. The anal margin is the darker-coloured skin that surrounds the opening to your anus.
Adenocarcinoma. This develops in cells that produce mucus within your anal canal. Doctors treat it in the same way as rectal cancer.
Basal cell carcinoma. This is a type of skin cancer that can develop in the skin around your anus.
Malignant melanoma. This is another type of skin cancer that you can get around your anus. It starts in cells called melanocytes. Doctors treat it in the same way as other melanomas.

Rare types of anal cancer include lymphoma and gastrointestinal stromal tumours.

Causes of anal cancer

The main cause of the squamous cell carcinoma type of anal cancer (anal squamous cell carcinoma) is thought to be human papillomavirus (HPV). This is a sexually transmitted virus, which is also linked to cervical cancer and genital warts.

Some things increase your risk of both HPV infection and anal cancer. These are:

having sex with many partners
having anal sex – particularly if you’re a man who has sex with other men

There are some other things that can increase your risk of anal cancer. Examples include:

if you have HIV/AIDS
if your immune system is weakened
if you have a history of cervical cancer.
if you’re a woman (women are more likely than men to develop anal cancer)
smoking and getting older

Symptoms of anal cancer

The most common symptoms of anal cancer are:

bleeding from your bottom – you may see blood in your poo or on toilet paper
pain around your bottom
a small lump or lumps around your anus

Other symptoms of anal cancer include:

feeling very itchy around your bottom
a discharge coming from your anus
difficulty controlling when you poo, which is called faecal incontinence

If you have these symptoms and they don’t seem to be getting better, go and see your GP. Bleeding from your bottom is a common symptom linked to other conditions, such as piles(haemorrhoids). But it’s worth getting checked by a doctor. Don’t put it off – cancers are usually easier to treat if you catch them early.

Diagnosis of anal cancer

Your GP will ask about your symptoms and your medical history.

Your GP may ask to examine your bottom to check if they can feel anything wrong. They’ll do this by feeling inside your bottom with their finger (they’ll wear a glove and use lubrication). Although it might feel a little uncomfortable, it shouldn’t be painful.

If you have a vagina, your GP may also examine inside your vagina to check if a tumour has spread to there.

Your GP may refer you to a doctor who specialises in bowel conditions. Your GP or specialist can arrange further tests if these are needed.

Tests to diagnose anal cancer

Several tests are used to diagnose anal cancer.

You may have a blood test to check your general health and to rule out other health conditions that could cause your symptoms.

A specialist doctor can do further tests that look inside your bowel, for example:

anoscopy – your doctor will use a thin tube to look inside your anus
proctoscopy – your doctor will use a slightly longer tube to look at your back passage (rectum)
sigmoidoscopy – your doctor will use a longer tube to look further inside your large bowel

You’ll usually have these tests as an out-patient (you won’t need to stay in hospital). They can be uncomfortable but shouldn’t be painful. Your doctor may take a small sample of tissue (a biopsy) during the test. They’ll send this to a laboratory for testing to find out whether the cells are cancerous or not.

You may also have a test under general anaesthesia to allow your doctor to do a more thorough examination and to take a biopsy.

Staging

If tests show that you have anal cancer, you’ll need to have more tests to find out how big it is and if it’s spread. This process is known as staging. You may have the following tests in different parts of your body:

a computer tomography scan (CT scan)
an X-ray of your chest and tummy (abdomen), to see if the cancer has spread (metastasised)
an MRI scan
a PET-CT scan (a type of CT scan that uses a radioactive dye to show up cancer cells)
an ultrasound
tests on your lymph nodes – a doctor will use a small needle to take a sample of cells from your groin

Looking for cancer cover that supports you every step of the way?

If you develop new conditions in the future, you can rest assured that our health insurance comes with full cancer cover as standard.

To get a quote or to make an enquiry, call us on 0808 273 6216^∧

Find out more about Bupa health insurance

Hello, I am Dr Naveen Puri, I am one of the GPs within Bupa Health Clinics.

Today I want to speak to you about embarrassing problems you might have and what we can do if you attend one of our clinics.

I want you to know that many people feel embarrassed or concerned about speaking about certain things with their doctors, but I'm here to reassure you these are the kinds of things we deal with every day.

For me, looking at someone's bottom or their breasts or their genitalia is no different to looking at their nose or elbow.

And that's true for all doctors as we train for many years in these parts of the body and are very used to having these conversations with people just like you.

So what I would encourage you to do if you have any concerns from your perspective, be it a change in your bowel habit, be it a lump, a rash, a swelling. Something on your genitalia or a part of your body you're not particularly familiar with or feel uncomfortable discussing.

Please be assured your doctor has done it all before.

Some of the ways we find patients find it easier to speak to a doctor is to either tell the doctor you feel embarrassed up front. That way a doctor can make extra effort to make sure you feel comfortable.

Or some patients come to us with pieces of paper and will write the problem down and hand it to us. That way we can help with whatever is going on for you as well.

You may also find it helpful to ask for a specific doctor, someone you're familiar with in your practice. Or you might want to ask for a doctor of a specific gender, or background to your liking as well.

I'd also say, doctors do this every day so don't be alarmed if we ask you certain questions around your symptoms. It is purely so we can help you get the best outcome for your enquiry.

And then finally, feel free to use language that suits you as well. We don't expect you to know the medical words for things, or a name for your diagnosis. That's our job to find out for you.

So, take your time, see a doctor, and hopefully we can help put your mind at ease.

Hello, I am Dr Naveen Puri, I am one of the GPs within Bupa Health Clinics.

Today I want to speak to you about embarrassing problems you might have and what we can do if you attend one of our clinics.

For me, looking at someone's bottom or their breasts or their genitalia is no different to looking at their nose or elbow.

And that's true for all doctors as we train for many years in these parts of the body and are very used to having these conversations with people just like you.

Please be assured your doctor has done it all before.

Or some patients come to us with pieces of paper and will write the problem down and hand it to us. That way we can help with whatever is going on for you as well.

I'd also say, doctors do this every day so don't be alarmed if we ask you certain questions around your symptoms. It is purely so we can help you get the best outcome for your enquiry.

And then finally, feel free to use language that suits you as well. We don't expect you to know the medical words for things, or a name for your diagnosis. That's our job to find out for you.

So, take your time, see a doctor, and hopefully we can help put your mind at ease.

Treatment of anal cancer

A multidisciplinary team (MDT) will manage your treatment. An MDT is a team of healthcare professionals with different specialities, including doctors specialised in diagnosing and treating anal cancer, and specialist nurses. Your treatment will depend on the type of anal cancer you have, and how far it’s spread. Your MDT will discuss what your options are. After you’ve finished your treatment, you’ll need to have regular check-ups with your doctor.

Chemoradiotherapy

The most common treatment for anal cancer is a combination of chemotherapy and radiotherapy, which is called chemoradiotherapy. This uses medicines and radiation together to destroy cancer cells. You’ll have a treatment plan that’s tailored to your needs, depending on services and guidelines available in your local area.

You’ll usually have your treatment over five weeks, with chemotherapy on the first and last weeks, and radiotherapy throughout. You’ll usually have two different chemotherapy medicines – mitomycin and either fluorouracil or capecitabine. These can be put into your bloodstream through a thin tube (cannula) in your arm or a long tube into a vein in your chest. Capecitabine is taken as a tablet. You’ll usually have the radiotherapy every weekday for the five-week treatment period.

Surgery

Sometimes, your doctor may recommend you have surgery to remove your cancer. The operation you have will depend on the stage of your cancer.

Local excision

Your MDT might offer you surgery if the tumour is small and just affects the area around the opening to your bottom (the anal margin). This is called a local excision. A surgeon will remove the tumour along with some normal skin and tissue around it.

Abdominoperineal resection (AP resection)

Your MDT may advise surgery to remove the cancer if you’ve had chemoradiotherapy that hasn’t worked or if your cancer has come back after treatment. In this surgery, which is called abdominoperineal resection, a surgeon will remove your anus, rectum, and part of your large bowel. It’s often called ‘salvage surgery’ because it’s a second chance of curing your cancer when other treatment hasn’t worked.

As part of this operation, you’ll need to have a colostomy. This is when the new end of your bowel is brought out through an opening in your skin and attached to the surface of your tummy (abdomen). The opening is known as a stoma. You’ll need to wear a bag over your stoma, which will collect poo. It may take a while to adjust to living with a stoma, but your doctor or stoma nurse will give you help and advice.

Prevention of anal cancer

Vaccination against HPV can help to protect against anal squamous cell carcinoma. In the UK, this is offered to all children aged 12 to 13. You can also get the HPV vaccine free through a sexual health clinic if you’re a man who has sex with men, and you’re under 45. Anyone can pay to have the vaccine privately through a pharmacy, health clinic or sometimes your GP.

Other things you can do to reduce your risk of anal cancer include:

wearing condoms when you have sex
giving up smoking if you smoke

Living with anal cancer

You may need to make some changes to your diet while you’re having treatment for anal cancer. Chemotherapy and radiotherapy can cause diarrhoea and might make you feel sick. Your treatment team can give you medicines to help with diarrhoea and sickness. These can be adjusted to make you as comfortable as possible during treatment.

It may help to eat less fibre during your treatment and for a few weeks afterwards, while you recover. This means not eating wholegrain cereals or breads, or fruit and vegetables that are high in fibre. Once your digestion has settled down again, you can gradually reintroduce more fibre to your diet.

If you need to have a colostomy, it’s likely you’ll need to make a number of changes to how often you eat, and what you eat. This can take a while to come to terms with.

After a diagnosis of anal cancer, you’re likely to have a range of emotions. As well as the emotional aspects, there can be a lot of practical issues to sort out. These include telling other people and taking time off work. Talk to your family and friends to help them to understand what you’re going through and how you’re feeling. Organisations and support groups can also be a great source of information and support.

For more information, see our section: Other helpful websites.

The most common symptom of anal cancer is bleeding from your bottom. Other symptoms include pain, a discharge from your bottom, and itchiness. You might feel a lump around your bottom too.

For more information, see our section: Symptoms of anal cancer.

The symptoms of haemorrhoids (piles) and anal cancer can be similar – both can cause bleeding and make your bottom feel itchy. Your doctor can do a simple test to check which you have. Although bleeding from your bottom is more likely to be due to piles, it’s important to check.

Anal cancer is rare type of cancer – about 1,500 people are diagnosed with it each year in the UK

Other helpful websites

Discover other helpful health information websites.

Did our Anal cancer information help you?

We’d love to hear what you think.^∧ Our short survey takes just a few minutes to complete and helps us to keep improving our health information.

^∧The health information on this page is intended for informational purposes only. We do not endorse any commercial products, or include Bupa's fees for treatments and/or services. For more information about prices visit: www.bupa.co.uk/health/payg

Complete 2 mins survey

This information was published by Bupa's Health Content Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals and deemed accurate on the date of review. Photos are only for illustrative purposes and do not reflect every presentation of a condition.

Any information about a treatment or procedure is generic, and does not necessarily describe that treatment or procedure as delivered by Bupa or its associated providers.

The information contained on this page and in any third party websites referred to on this page is not intended nor implied to be a substitute for professional medical advice nor is it intended to be for medical diagnosis or treatment. Third party websites are not owned or controlled by Bupa and any individual may be able to access and post messages on them. Bupa is not responsible for the content or availability of these third party websites. We do not accept advertising on this page.

Anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed June 2022
What is anal cancer? American Cancer Society. Cancer.org, last revised November 2017
Anal cancer. Bowel Cancer UK. bowelcanceruk.org.uk, updated August 2018
What is anal cancer? Cancer Research UK. cancerresearchuk.org, last reviewed June 2022
Symptoms of anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed June 2022
Anal cancer. Macmillan. Macmillan.org.uk, last reviewed April 2020
Anal cancer incidence statistics – anal cancer incidence projections. Cancer Research UK. cancerresearchuk.org, last reviewed February 2023
Anal cancer – practice essentials. Medscape. emedicine.medscape.com, updated September 2022
Types of anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed July 2022
Anal carcinoma. Patient. patient.info/doctor, last updated May 2023
Risks and causes of anal cancer. Cancer Research UK. cancerresearchu.org, last reviewed October 2022
Human papilloma virus (HPV). Macmillan. Macmillan.org.uk, reviewed April 2021
HPV and cancer. National Cancer Institute. Cancer.gov, updated April 2023
Human papillomavirus (HPV) vaccination. Patient. patient.info/doctor, last updated November 2021
Anal cancer. BMJ Best Practice. bestpractice.bmj.com, last updated February 2024
Anal cancer treatment (PDQ) – patient version. National Cancer Institute. Cancer.gov, updated December 2022
Seeing your GP when you have symptoms of anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed June 2022
Anal cancer. Oxford Handbook of Oncology. Oxford Academic. academic.oup.com, published August 2015
Blood tests for anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed July 2022
Anal examination and biopsy. Cancer Research UK. cancerresearchuk.org, last reviewed June 2022
CT scan for anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed 8 July 2022
MRI scan for anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed July 2022
PET-CT scan for anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed July 2022
Bowel cancer. Cancer Research UK. cancerresearchuk.org, last reviewed Feb 2022
Gastrointestinal tract (lower) cancers – recognition and referral. NICE Clinical Knowledge Summaries. cks.nice.org.uk, last revised August 2023
Anoscopy and sigmoidoscopy. MSD Manuals. msdmanuals.com, reviewed March 2023
Ultrasound of the anus. Cancer Research UK. cancerresearchuk.org, last reviewed July 2022
Fine needle aspiration of lymph nodes for anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed July 2022
Your multidisciplinary team (MDT). Macmillan Cancer Support. macmillan.org.uk, reviewed July 2018
Winters DA, Soukup T, Sevdalis N, et al. The cancer multidisciplinary team meeting: in need of change? History, challenges and future perspectives. BJU Int 2021; 128:271–79. DOI:10.1111/bju.15495
Geh I, Gollins S, Renehan A, et al. Association of Coloproctology of Great Britain & Ireland (ACPGBI): Guidelines for the Management of Cancer of the Colon, Rectum and Anus (2017) - Anal Cancer. Colorectal Dis 2017; 19:82–97. DOI: 10.1111/codi.13709
Treatment options for anal cancer. Cancer Research UK. Cancerresearchuk.org, last reviewed December 2022
Chemoradiotherapy for anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed December 2022
Types of surgery for anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed July 2022
Surgery for anal cancer. Macmillan Cancer Support. macmillan.org.uk, reviewed April 2020
Having the HPV vaccine privately. Jo’s Cervical Cancer Trust. jostrust.org.uk, last updated June 2022
Diet after anal cancer treatment. Cancer Research UK. cancerresearchuk.org, last reviewed August 2022
Coping with anal cancer. Cancer Research UK. cancerresearchuk.org, last reviewed August 2022

Our information has been awarded the PIF tick for trustworthy health information.