Health A to Z
Bowel cancer is a general term for cancer that begins in the large bowel. Depending on where the cancer starts, bowel cancer is sometimes called colon or rectal cancer.
Bowel cancer is one of the most common types of cancer diagnosed in the UK. Most people diagnosed with it are over the age of 60.
This page covers:
The three main symptoms of bowel cancer are:
The symptoms of bowel cancer can be subtle and don't necessarily make you feel ill.
However, it's worth waiting for a short time to see if they get better as the symptoms of bowel cancer are persistent.
If you're unsure whether to see your GP, try the bowel cancer symptom checker.
Bowel cancer symptoms are also very common, and most people with them don't have cancer.
These symptoms should be taken more seriously as you get older and when they persist despite simple treatments.
Read about the symptoms of bowel cancer.
Try the bowel cancer symptom checker for advice on what you can try to see if your symptoms get better, and when you should see your GP to discuss whether tests are necessary.
Your doctor may decide to:
Make sure you see your doctor if your symptoms persist or keep coming back after stopping treatment, regardless of their severity or your age. You'll probably be referred to hospital.
Read about diagnosing bowel cancer.
It's not known exactly what causes bowel cancer, but there are a number of things that can increase your risk.
Although there are some risks you can't change, such as your family history or your age, there are several ways you can lower your chances of developing the condition.
Read more about the causes of bowel cancer.
To detect cases of bowel cancer sooner, the NHS offers two types of bowel cancer screening to adults registered with a GP in England:
Taking part in bowel cancer screening reduces your chances of dying from bowel cancer. Removing any polyps found in bowel scope screening can prevent cancer.
However, all screening involves a balance of potential harms, as well as benefits. It's up to you to decide if you want to have it.
To help you decide, read our pages on bowel cancer screening, which explain what the two tests involve, what the different possible results mean, and the potential risks for you to weigh up.
Read more about screening for bowel cancer.
Bowel cancer can be treated using a combination of different treatments, depending on where the cancer is in your bowel and how far it has spread.
The main treatments are:
As with most types of cancer, the chance of a complete cure depends on how far it has advanced by the time it's diagnosed. If the cancer is confined to the bowel, surgery is usually able to completely remove it.
Keyhole or robotic surgery is being used more often, which allows surgery to be performed with less pain and a quicker recovery.
Read more about how bowel cancer is treated.
Bowel cancer can affect your daily life in different ways, depending on what stage it's at and the treatment you're having.
How people cope with their diagnosis and treatment varies from person to person. There are several forms of support available if you need it:
You may also want advice on recovering from surgery, including diet and living with a stoma, and any financial concerns you have.
If you're told there's nothing more that can be done to treat your bowel cancer, there's still support available from your GP. This is known as palliative care.
Read about living with bowel cancer.
The symptoms of bowel cancer can be subtle and don't necessarily make you feel ill. However, it's worth trying simple treatments for a short time to see if they get better.
More than 90% of people with bowel cancer have one of the following combinations of symptoms:
Constipation, where you pass harder stools less often, is rarely caused by serious bowel conditions.
Although bowel cancer symptoms are very common, you should see your GP if they persist for more than four weeks. Most people with these symptoms don't have bowel cancer.
Try the bowel cancer symptom checker for advice on what treatments you can try to see if your symptoms get better, and when you should see your GP to discuss whether any tests are necessary.
See your doctor if your symptoms persist or keep coming back after stopping treatment, regardless of their severity or your age.
Read more about diagnosing bowel cancer.
In some cases, bowel cancer can stop digestive waste passing through the bowel. This is known as a bowel obstruction.
Symptoms of a bowel obstruction can include:
A bowel obstruction is a medical emergency. If you suspect your bowel is obstructed, you should see your GP quickly. If this isn't possible, go to the accident and emergency (A&E) department of your nearest hospital.
The exact cause of bowel cancer is still unknown. However, research has shown several factors may make you more likely to develop it.
Cancer occurs when the cells in a certain area of your body divide and multiply too rapidly. This produces a lump of tissue known as a tumour.
Most cases of bowel cancer first develop inside clumps of cells called polyps on the inner lining of the bowel.
However, it doesn't necessarily mean you'll get bowel cancer if you develop polyps.
Some polyps regress, and some don't change. Only a few grow and eventually develop into bowel cancer over a period of several years.
The main risk factors for bowel cancer are outlined below.
Around 1 in 20 people develop bowel cancer. Almost 18 out of 20 cases of bowel cancer in the UK are diagnosed in people over the age of 60.
Having a family history of bowel cancer in a first-degree relative – a mother, father, brother or sister – under the age of 50 can increase your lifetime risk of developing the condition yourself.
If you're particularly concerned that your family's medical history may mean you're at an increased risk of developing bowel cancer, it may help to speak to your GP.
If necessary, your GP can refer you to a genetics specialist, who can offer more advice about your level of risk and recommend any necessary tests to periodically check for the condition.
A large body of evidence suggests a diet high in red and processed meat can increase your risk of developing bowel cancer.
For this reason, the Department of Health advises people who eat more than 90g (cooked weight) a day of red and processed meat cut down to 70g a day.
Read more about red meat and bowel cancer risk.
There's also evidence that suggests a diet high in fibre could help reduce your bowel cancer risk.
Read more about eating good food and a healthy diet.
People who smoke cigarettes are more likely to develop bowel cancer, as well as other types of cancer and other serious conditions, such as heart disease.
Read more about stopping smoking.
Drinking alcohol has been shown to be associated with an increased risk of bowel cancer, particularly if you regularly drink large amounts.
Read about drinking and alcohol for more information and tips on cutting down.
Being overweight or obese is linked to an increased risk of bowel cancer, particularly in men.
If you're overweight or obese, losing weight may help lower your chances of developing the condition.
People who are physically inactive have a higher risk of developing bowel cancer.
You can help reduce your risk of bowel and other cancers by being physically active every day.
Read more about health and fitness.
Some conditions affecting the bowel may put you at a higher risk of developing bowel cancer.
If you have one of these conditions, you'll usually have regular check-ups to look for signs of bowel cancer from about 10 years after your symptoms first develop.
Check-ups involve examining your bowel with a colonoscope – a long, narrow flexible tube that contains a small camera. This is inserted into your bottom.
The frequency of the colonoscopy examinations will increase the longer you live with the condition. This also depends on factors such as how severe your ulcerative colitis is and whether you have a family history of bowel cancer.
There are two rare inherited conditions that can lead to bowel cancer:
Although the polyps caused by FAP are non-cancerous, there's a high risk that over time at least one will turn cancerous. Most people with FAP have bowel cancer by the time they're 50.
As people with FAP have such a high risk of getting bowel cancer, they're often advised by their doctor to have their large bowel removed before they reach the age of 25.
Families affected can find support and advice from FAP registries such as The Polyposis Registry provided by St Mark's Hospital, London.
Removing the bowel as a precautionary measure is also usually recommended in people with HNPCC as the risk of developing bowel cancer is so high.
When you first see your GP, they'll ask about your symptoms and whether you have a family history of bowel cancer.
They'll usually carry out a simple examination of your bottom, known as a digital rectal examination (DRE), and examine your tummy (abdomen).
This is a useful way of checking whether there are any lumps in your tummy or back passage.
The tests can be uncomfortable, and most people find an examination of the back passage a little embarrassing, but they take less than a minute.
Your GP will also check your blood to see if you have iron deficiency anaemia.
Although most people with bowel cancer don't have symptoms of anaemia, they may have a lack of iron as a result of bleeding from the cancer.
In most people with bowel cancer, iron deficiency anaemia is found incidentally.
If your symptoms suggest you may have bowel cancer or the diagnosis is uncertain, you'll be referred to your local hospital for a simple examination called a flexible sigmoidoscopy.
A small number of cancers can only be diagnosed by a more extensive examination of the colon. The two tests used for this are colonoscopy or computerised tomography (CT) colonography.
Emergency referrals, such as people with bowel obstruction, will be diagnosed by a CT scan. Those with severe iron deficiency anaemia and few or no bowel symptoms are usually diagnosed by colonoscopy.
These tests are described in more detail below.
A flexible sigmoidoscopy is an examination of your back passage (rectum) and some of your large bowel using a device called a sigmoidoscope.
A sigmoidoscope is a long, thin, flexible tube attached to a very small camera and light. It's inserted into your rectum and up into your bowel.
The camera relays images to a monitor and can also be used to take biopsies, where a small tissue sample is removed for further analysis.
It's better for your lower bowel to be as empty as possible when sigmoidoscopy is performed, so you may be asked to carry out an enema – a simple procedure to flush your bowels – at home beforehand.
This should be used at least two hours before you leave home for your appointment.
A sigmoidoscopy can feel uncomfortable, but it only takes a few minutes and most people go home straight after the examination.
A colonoscopy is an examination of your entire large bowel using a device called a colonoscope, which is like a sigmoidoscope but a bit longer.
Your bowel needs to be empty when a colonoscopy is performed, so you'll be advised to eat a special diet for a few days beforehand and take a medication to help empty your bowel (laxative) on the morning of the examination.
You'll be given a sedative to help you relax during the test. The doctor will then insert the colonoscope into your rectum and move it along the length of your large bowel. This isn't usually painful, but can feel uncomfortable.
The camera relays images to a monitor, which allows the doctor to check for any abnormal areas within the rectum or bowel that could be the result of cancer. As with a sigmoidoscopy, a biopsy may also be performed during the test.
A colonoscopy usually takes about an hour to complete, and most people can go home once they've recovered from the effects of the sedative.
You will probably feel drowsy for a while after the procedure, so you'll need to arrange for someone to accompany you home.
It's best for elderly people to have someone with them for 24 hours after the test. You'll be advised not to drive for 24 hours.
In a small number of people, it may not be possible to pass the colonoscope completely around the bowel and it is then necessary to have CT colonography.
Watch a video on what happens during a colonoscopy.
CT colonography, also known as a "virtual colonoscopy", involves using a computerised tomography (CT) scanner to produce three-dimensional images of the large bowel and rectum.
During the procedure, gas is used to inflate the bowel using a thin, flexible tube placed in your rectum. CT scans are then taken from a number of different angles.
As with a colonoscopy, you may need to have a special diet for a few days and take a laxative before the test to ensure your bowels are empty when it's carried out. You may also be asked to take a liquid called gastrograffin before the test.
This test can help identify potentially cancerous areas in people who are not suitable for a colonoscopy because of other medical reasons.
A CT colonography is a less invasive test than a colonoscopy, but you may still need to have colonoscopy or flexible sigmoidoscopy at a later stage so any abnormal areas can be removed or biopsied.
If a diagnosis of bowel cancer is confirmed, further testing is usually carried out to check if the cancer has spread from the bowel to other parts of the body. These tests also help your doctors decide on the most effective treatment for you.
These tests can include:
After all tests have been completed, it's usually possible to determine the stage of your cancer.
There are two ways that bowel cancer can be staged. The first is known as the TNM staging system:
Bowel cancer is also staged numerically. The four main stages are:
Cancer Research UK has more information about bowel cancer stages.
If colon cancer is at a very early stage, it may be possible to remove just a small piece of the lining of the colon wall, known as local excision.
If the cancer spreads into muscles surrounding the colon, it's usually necessary to remove an entire section of your colon, known as a colectomy.
There are three ways a colectomy can be performed:
During robotic surgery, there's no direct connection between the surgeon and the patient, which means it would be possible for the surgeon to not be in the same hospital as the patient. Robotic surgery is not available in many centres in the UK at the moment.
During surgery, nearby lymph nodes are also removed. It's usual to join the ends of the bowel together after bowel cancer surgery, but very occasionally this isn't possible and a stoma is needed.
Both open and laparoscopic colectomies are thought to be equally effective at removing cancer, and have similar risks of complications.
However, laparoscopic or robotic colectomies have the advantage of a faster recovery time and less postoperative pain. Laparoscopic surgery is now becoming the routine way of doing most of these operations.
Laparoscopic colectomies should be available in all hospitals that carry out bowel cancer surgery, although not all surgeons perform this type of surgery. Discuss your options with your surgeon to see if this method can be used.
There are a number of different types of operation that can be carried out to treat rectal cancer, depending on how far the cancer has spread.
Some operations are entirely through the bottom, with no need for abdominal incisions.
Some of the main techniques used are described below.
If you have a very small early-stage rectal cancer, your surgeon may be able to remove it in an operation called a local resection (transanal, through the bottom resection).
The surgeon puts an endoscope in through your back passage and removes the cancer from the wall of the rectum.
In most cases, a local resection isn't possible at the moment. Instead, a larger area of the rectum will need to be removed.
This area will include a border of rectal tissue free of cancer cells, as well as fatty tissue from around the bowel (the mesentery). This type of operation is known as total mesenteric excision (TME).
Removing the mesentery can help ensure all the cancerous cells are removed, which can lower the risk of the cancer recurring at a later stage.
Depending on where in your rectum the cancer is located, one of two main types of TME operations may be carried out. These are outlined below.
Low anterior resection is a procedure used to treat cases where the cancer is away from the sphincters that control bowel action.
The surgeon will make an incision in your abdomen and remove part of your rectum, as well as some surrounding tissue to make sure any lymph glands containing cancer cells are also removed.
They then attach your colon to the lowest part of your rectum or upper part of the anal canal. Sometimes they turn the end of the colon into an internal pouch to replace the rectum.
You'll probably require a temporary stoma to give the joined section of bowel time to heal. This will be closed at a second, less major, operation.
Abdominoperineal resection is used to treat cases where the cancer is in the lowest section of your rectum.
In this case, it's usually necessary to remove the whole of your rectum and surrounding muscles to reduce the risk of the cancer regrowing in the same area.
This involves removing and closing the anus and removing its sphincter muscles, so there's no option except to have a permanent stoma after the operation.
Bowel cancer surgeons always do their best to avoid giving people permanent stomas wherever possible.
Where a section of the bowel is removed and the remaining bowel joined, the surgeon may sometimes decide to divert your faeces away from the join to allow it to heal.
The faeces are temporarily diverted by bringing a loop of bowel out through the abdominal wall and attaching it to the skin – this is called a stoma. A bag is worn over the stoma to collect the faeces.
A specialist nurse known as a stoma care nurse can advise you on the best site for a stoma prior to surgery.
The nurse will take into account factors such as your body shape and lifestyle, although this may not be possible where surgery is performed in an emergency.
In the first few days after surgery, the stoma care nurse will advise on the care necessary to look after the stoma and the type of bag suitable.
Once the join in the bowel has safely healed, which can take several weeks, the stoma can be closed during further surgery.
For various reasons, in some people rejoining the bowel may not be possible or may lead to problems controlling bowel function, and the stoma may become permanent.
Before having surgery, the care team will advise you about whether it may be necessary to form an ileostomy or colostomy, and the likelihood of this being temporary or permanent.
There are patient support groups available that provide support for patients who have just had or are about to have a stoma. You can get more details from your stoma care nurse, or visit the groups online for further information.
Bowel cancer operations carry many of the same risks as other major operations, including:
The operations all carry a number of risks specific to the procedure. One risk is that the joined up section of bowel may not heal properly and leak inside your abdomen. This is usually only a risk in the first few days after the operation.
Another risk is for people having rectal cancer surgery. The nerves that control urination and sexual function are very close to the rectum, and sometimes surgery to remove a rectal cancer can damage these nerves.
After rectal cancer surgery, most people need to go to the toilet to open their bowels more often than before, although this usually settles down within a few months of the operation.
Occasionally, some people – particularly men – have other distressing symptoms, such as pain in the pelvic area and constipation alternating with frequent bowel motions. Frequent bowel motions can lead to severe soreness around the anal canal.
Support and advice should be offered on how to cope with these symptoms until the bowel adapts to the loss of part of the back passage.
There are two main ways radiotherapy can be used to treat bowel cancer. It can be given either:
Radiotherapy given before surgery for rectal cancer can be performed in two ways:
External radiotherapy is usually given daily, five days a week, with a break at the weekend.
Depending on the size of your tumour, you may need one to five weeks of treatment. Each session of radiotherapy is short and will only last for 10 to 15 minutes.
Internal radiotherapy can usually be performed in one session before surgery is carried out a few weeks later.
Palliative radiotherapy is usually given in short daily sessions, with a course ranging from two to three days, up to 10 days.
Short-term side effects of radiotherapy can include:
These side effects should pass once the course of radiotherapy has finished.
Tell your care team if the side effects of treatment become particularly troublesome. Additional treatments are often available to help you cope with the side effects better.
Long-term side effects of radiotherapy can include:
If you want to have children, it may be possible to store a sample of your sperm or eggs before treatment begins so they can be used in fertility treatments in the future.
There are three ways chemotherapy can be used to treat bowel cancer:
Chemotherapy for bowel cancer usually involves taking a combination of medications that kill cancer cells.
They can be given as a tablet (oral chemotherapy), through a drip in your arm (intravenous chemotherapy), or as a combination of both.
Treatment is given in courses (cycles) that are two to three weeks long each, depending on the stage or grade of your cancer.
A single session of intravenous chemotherapy can last from several hours to several days.
Most people having oral chemotherapy take tablets over the course of two weeks before having a break from treatment for another week.
A course of chemotherapy can last up to six months, depending on how well you respond to the treatment.
In some cases, it can be given in smaller doses over longer periods of time (maintenance chemotherapy).
Side effects of chemotherapy can include:
These side effects should gradually pass once your treatment has finished. It usually takes a few months for your hair to grow back if you experience hair loss.
Chemotherapy can also weaken your immune system, making you more vulnerable to infection.
Inform your care team or GP as soon as possible if you experience possible signs of an infection, including a high temperature (fever) or a sudden feeling of being generally unwell.
Medications used in chemotherapy can cause temporary damage to men's sperm and women's eggs. This means there's a risk to the unborn baby's health for women who become pregnant or men who father a child.
It's recommended that you use a reliable method of contraception while having chemotherapy treatment and for a period after your treatment has finished.
Biological treatments, including cetuximab and panitumumab, are newer medicines also known as monoclonal antibodies.
They target special proteins, called epidermal growth factor receptors (EGFRs), found on the surface of some cancer cells.
As EGFRs help the cancer grow, targeting these proteins can help shrink tumours and improve the effect of chemotherapy.
Biological treatments are sometimes used in combination with chemotherapy when the cancer has spread beyond the bowel (metastatic bowel cancer).
Your GP or nurse may be able to reassure you if you have questions, or you may find it helpful to talk to a trained counsellor, psychologist or specialist telephone helpline operator. Your GP surgery will have information on these.
Some people find it helpful to talk to others with bowel cancer at a local support group or through an internet chat room.
Beating Bowel Cancer offers support services to people with bowel cancer. They run a nurse advisory line on 08450 719 301 or 020 8973 0011, available 9am to 5.30pm Monday to Thursday and 9am to 4pm on Fridays.
You can also email a nurse at firstname.lastname@example.org.
The organisation also runs a national patient-to-patient network called Bowel Cancer Voices for people affected by bowel cancer and their relatives.
Having cancer can cause a range of emotions. These may include shock, anxiety, relief, sadness and depression.
Different people deal with serious problems in different ways. It's hard to predict how knowing you have cancer will affect you.
However, you and your loved ones may find it helpful to know about the feelings that people diagnosed with cancer have reported.
Surgeons and anaesthetists have found using an enhanced recovery programme after bowel cancer surgery helps patients recover more quickly.
Most hospitals now use this programme. It involves giving you more information about what to expect before the operation, avoiding giving you strong laxatives to clean the bowel before surgery, and in some cases giving you a sugary drink two hours before the operation to give you energy.
During and after the operation, the anaesthetist controls the amount of IV fluid you need very carefully. After the operation, you'll be given painkillers that allow you to get up and out of bed by the next day.
Most people will be able to eat a light diet the day after their operation.
To reduce the risk of blood clots in the legs (deep vein thrombosis), you may be given special compression stockings that help prevent blood clots, or a regular injection with a blood-thinning medication called heparin until you're fully mobile.
A nurse or physiotherapist will help you get out of bed and regain your strength so you can go home within a few days.
With the enhanced recovery programme, most people are well enough to go home within a week of their operation.
The timing depends on when you and the doctors and nurses looking after you agree you're well enough to go home.
You'll be asked to return to hospital a few weeks after your treatment has finished so tests can be carried out to check for any remaining signs of cancer.
You may also need routine check-ups for the next few years to look out for signs of the cancer recurring. It's becoming increasingly possible to cure cancers that recur after surgery.
If you've had part of your colon removed, it's likely you'll experience some diarrhoea or frequent bowel motions.
One of the functions of the colon is to absorb water from stools and empty when going to the toilet.
After surgery, the bowel initially doesn't empty as well, particularly if part of the rectum has been removed.
Inform your care team if this becomes a problem, as medication is available to help control these problems.
You may find some foods upset your bowels, particularly during the first few months after your operation.
Different foods can upset different people, but food and drink known to cause problems include fruit and vegetables that are high in fibre, such as beans, cabbages, apples and bananas, and fizzy drinks, such as cola and beer.
You may find it useful to keep a food diary to record the effects of different foods on your bowel.
Contact your care team if you find you're having continual problems with your bowels as a result of your diet, or you're finding it difficult to maintain a healthy diet. You may need to be referred to a dietitian for further advice.
If you need a temporary or permanent stoma with an external bag or pouch, you may feel worried about how you look and how others will react to you.
For those who want further information about living with a stoma, there are patient support groups that provide support for people who may have had, or are due to have, a stoma.
You can get more details from your stoma care nurse, or visit support groups online for further information:
Having cancer and receiving treatment may affect how you feel about relationships and sex.
Although most people are able to enjoy a normal sex life after bowel cancer treatment, you may feel self-conscious or uncomfortable if you have stoma.
Talking about how you feel with your partner may help you both support each other. Or you may feel you'd like to talk to someone else about your feelings. Your doctor or nurse will be able to help.
A diagnosis of cancer can cause money problems because you're unable to work, or someone you're close to has to stop working to look after you.
There's financial support available for carers and yourself if you have to stay off work for a while or stop work because of your illness.
People being treated for cancer are entitled to apply for an exemption certificate giving free prescriptions for all medication, including medication to treat unrelated conditions.
The certificate is valid for five years. You can apply for one by speaking to your GP or cancer specialist.
If you're told there's nothing more that can be done to treat your bowel cancer, your GP will still provide you with support and pain relief. This is called palliative care.
Support is also available for your family and friends.
Anne Messenger, from London, was diagnosed with bowel cancer in 2005. After keyhole surgery, she is now in the clear and focused on helping others.
"For years I'd suffered from indigestion and thought I had irritable bowel syndrome, but when I noticed I had passed a little bit of blood, I went to the doctor.
"I was referred to St George's Hospital for tests and, following a stool sample, I was told I had a peptic ulcer. However, when I had a routine colonoscopy, doctors discovered that it was bowel cancer.
"It turned out that the initial bleeding had nothing to do with the cancer, so I'm fortunate that whatever caused it put me in a position where the doctors could pick up the cancer.
"Not long after my diagnosis, I was given a date for an operation to remove the cancer. I had a full body scan, and the consultant told me that everything looked straightforward. They would perform keyhole surgery and I wouldn't need a colostomy.
"Leading up to the surgery, I had another colonoscopy, in which purple dye was used to pinpoint where doctors needed to operate. I never thought I'd have any problems, as I was naturally upbeat.
"The operation went well and they removed an 8cm (3 inch) growth. Doctors told me there was a 20% chance of recurrence, which would be halved if I had a course of chemotherapy.
"I began chemotherapy two weeks after my operation, but I had a bad reaction to it and had to stop.
"For the two years after my operation, I had a check-up every three months. I now have one every six months.
"I had my last cigarette on the morning of my operation and I have become more aware of what I eat. My diet includes lots more fruit and veg.
"My advice is to try to take a bit of control and understand what is happening to you. Pay attention and always make a note of things to ask the consultant.
"You don't want to fuss, but you also don't want the consultant to say, 'You should have come to see me about this two months ago'.
"People can find doctors intimidating, but they're nice to everyone, so if something is worrying you, just ask.
"I used to call up or write to my doctor if I had any worries, and I'd take my husband with me if I was going to an appointment where I needed to take in information or make decisions about my treatment.
"Also, try to carry on as if you're going to be fine. I did, and because of that, my family coped well.
"I am now on the cancer committee at St George's. I think it's best to face cancer head on, and people who survive have a better view of life than most."
Lester and his wife Carolyn talk about his experience of bowel cancer, and offer their advice to others.