Small bowel cancer

The small bowel extends between the stomach and the large bowel (colon). Cancers in this area are rare. There are four main types of small bowel cancer. They are named after the cells where they develop:

  • Adenocarcinoma
  • Sarcoma
  • Neuroendocrine (carcinoid) tumours;
  • Lymphoma

The symptoms of small bowel cancer include:

  • cramping pain in the tummy
  • weight loss
  • nausea and vomiting
  • anaemia (a low number of red blood cells), due to blood loss
  • dark or black stools (bowel motions), due to bleeding in the small bowel
  • diarrhoea.

You will need tests to diagnose small bowel cancer. Tests may include endoscopies, x-rays, CT or MRI scans. Doctors may also need to collect tissue samples (biopsy) from the affected area.

Surgery is the main treatment for cancer of the small bowel. It may be used to remove the affected section of the bowel and join the bowel back together. Radiotherapy or chemotherapy may be used after surgery or used in combination (chemoradiation).

What is small bowel cancer?

The small bowel makes up three quarters of the digestive system, but cancers in this area are rare. Around 1,000 people in the UK are diagnosed with small bowel cancer each year.

We hope this information answers some of your questions. If you have any further questions, you can ask your doctor or nurse at the hospital where you are having your treatment.

The small bowel

The small bowel is part of the digestive system. It extends between the stomach and the large bowel (colon). The small bowel is divided into three main parts:

• the duodenum

• the jejunum

• the ileum.

The small bowel is around five metres (16 feet) long. It folds many times to fit inside your tummy (abdomen). It breaks down food, which allows vitamins, minerals and nutrients to be absorbed into your body.

The position and sections of the small bowel
The position and sections of the small bowel

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Types of small bowel cancer

There are four main types of small bowel cancer. They are named after the cells where they develop:


These tumours start in the lining of the bowel. They are the most common type of small bowel cancer. They usually occur in the duodenum.


These tumours develop in the supportive tissues of the body. There are different types of sarcoma. Leiomyosarcomas usually grow in the muscle wall of the small bowel, most often in the ileum. Another rare type of sarcoma is a gastrointestinal stromal tumour (GIST), which can develop in any part of the small bowel.

Neuroendocrine (carcinoid) tumours

These start from cells that make hormones inside the small bowel. These tumours appear most commonly in the ileum and sometimes in the appendix.


Lymphomas start in the lymph tissue of the small bowel. The lymph tissue is part of the body’s immune system. Small bowel lymphomas are usually non-Hodgkin lymphomas (NHLs).

Small bowel lymphomas occur most commonly in the jejunum or ileum.

Occasionally, a small bowel cancer may be a secondary cancer. This means it has spread from a primary cancer somewhere else in the body.

This information is mainly about adenocarcinoma of the small bowel.

Causes and risk factors of small bowel cancer

We don’t know what causes most small bowel cancers. But some people with non-cancerous bowel conditions may have a higher risk of developing small bowel cancer. These conditions include Crohn’s disease, coeliac disease and Peutz-Jegher’s syndrome.

People who have had a cancer of the colon or rectum have an increased risk of developing small bowel cancer. People who have hereditary non-polyposis colorectal cancer (HNPCC) or familial adenomatous polyposis (FAP) also have a higher risk.

Small bowel cancer, like all cancers, is not infectious and can't be passed on to other people.

Signs and symptoms of small bowel cancer

The symptoms of small bowel cancer are often vague and difficult to diagnose.

They may include:

  • cramping pain in the tummy
  • weight loss
  • nausea and vomiting
  • anaemia (a low number of red blood cells), due to blood loss
  • dark or black stools (bowel motions), due to bleeding in the small bowel
  • diarrhoea.

These symptoms may be caused by many things other than small bowel cancer. But you should always get symptoms checked by your doctor if they are severe, get worse or last for a few weeks.

Occasionally, the cancer can cause a blockage (obstruction) in the bowel. This may be a complete or partial blockage. The symptoms of this are vomiting, constipation, griping pain and a bloated feeling in the tummy (abdomen).

Sometimes a blockage in the small bowel can cause the bowel to tear. This is a serious condition that usually occurs suddenly and needs to be treated with surgery. The symptoms include severe pain, shock (a drop in blood pressure) and abdominal swelling.

How small bowel cancer is diagnosed

You will usually begin by seeing your GP, who will examine you and refer you to a hospital specialist. At the hospital, the doctor will ask you about your general health and any previous medical problems.

They will examine you and take blood samples. This is to check for anaemia and to check that your liver is working properly. You may be asked to take a sample of your stool (bowel movement) to the hospital so it can be tested for blood. You may also have some of the following tests:

Endoscopy or colonoscopy

An endoscopy looks inside the duodenum and the upper part of the jejunum. A colonoscopy looks along the lower part of the ileum. You have these tests in the hospital's outpatient department or on a ward.

You’ll be given a mild sedative to help you relax and you will lie on your side. If you have an endoscopy, the doctor gently passes a thin tube down your throat and through your stomach. If you have a colonoscopy, the doctor will gently pass a thin tube into your back passage. There is a light and lens at the end of the tube to help the doctor to see any abnormal areas.

During the endoscopy or colonoscopy, the doctor may take a small sample of tissue, called a biopsy. This will be examined in a laboratory by a pathologist.

Unfortunately, neither of these tests can reach some areas of the jejunum or the ileum. So different tests are needed to find tumours in these areas.

Capsule endoscopy

This test takes pictures of the whole of the inside of your digestive tract, including all of your small bowel.

You swallow a capsule that's about the size of a large pill. Inside the capsule is a camera, a battery, a light and a transmitter. The camera takes two pictures a second for eight hours. The pictures are sent to a small recording device, which is attached to a belt you wear round your waist.

You have to follow a special diet the day before and on the day of the test. Your nurse or doctor will give you instructions about this. Otherwise, you can carry on with your normal activities while the camera is taking pictures.

About eight hours after swallowing the capsule, you will need to return the recording device to the hospital. The pictures from the recorder are loaded on to a computer and your doctor will look at them. The capsule is disposable and is usually passed out naturally in bowel motions.

If you are concerned that the capsule has not passed out, contact your doctor. They may arrange an x-ray to check whether it has passed out.

Barium x-ray

This is a special x-ray of the small bowel. It is sometimes called a barium meal or barium follow-through. You have this in the hospital x-ray department. For this test, it's important that your bowel is empty so that the doctors can see your bowel clearly. The day before your test, you will probably be asked to take a laxative and drink plenty of fluids to help empty your bowel. Your hospital will give you instructions.

On the day of your barium x-ray, you should not eat or drink anything. You will be asked to drink a fluid that contains barium, which shows up white on an x-ray. The doctor will watch the barium pass through the whole of the small bowel on a screen, to look for any abnormalities.

Your stools may be white for a couple of days after the test. This is the barium passing out of your body. It is nothing to worry about. The barium can also cause constipation, so you may need to take a mild laxative for a couple of days.

CT scan

A CT (computerised tomography) scan uses x-rays to build a three-dimensional (3D) picture of the inside of the body. You may be given either a drink or injection of dye. This is to make certain areas of the body show up more clearly. This scan takes about 30 minutes and is painless. We have more detailed information about having a CT scan.

MRI scan

This scan uses magnetism to build up a detailed picture of areas of your body. You may be given an injection of dye, into a vein, to improve the images from the scan. This test is painless and will take about 30 minutes. We have more detailed information about having an MRI scan.

Other tests

Sometimes it's difficult to get a clear picture of the small bowel, and biopsies can't always be taken. If this happens, diagnosis may be made during an operation.

Staging of small bowel cancer

The stage of a cancer is a term used to describe its size and whether it has spread beyond its original site. Knowing the type and stage of the cancer helps the doctors to decide on the best 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 that are linked by fine tubes containing lymph fluid. Your doctors will usually check the lymph nodes close to the small bowel to help find the stage of the cancer. There are four stages of small bowel cancer:

Stage 1

The cancer is contained within the lining of the small bowel or has spread into the muscle wall, but has not begun to spread to the lymph nodes or other parts of the body.

Stage 2

The cancer has spread through the muscle wall and may affect other nearby structures, such as the pancreas.

Stage 3

The cancer has spread to nearby lymph nodes.

Stage 4

The cancer has spread to nearby lymph nodes and to other parts of the body, such as the liver or lungs.

If the cancer comes back after initial treatment, this is known as recurrent cancer.

Treatment for small bowel cancer

Treating adenocarcinoma of the small bowel will depend on a number of factors, including your general health, the position and size of the cancer, and whether it has spread to other areas of the body.

Surgery for small bowel cancer

Surgery is the main treatment for cancer of the small bowel. Surgery may be used to remove the affected section of the bowel and join the bowel back together. It may also be used if there is a blockage in the bowel.

Often, a surgeon can remove all of the tumour during an operation. But this isn’t the case for everyone. The position of the tumour within the bowel and how much of the bowel is involved will determine how extensive the surgery is. The surgeon may need to remove part of the stomach, part of the colon, the gall bladder or the surrounding lymph nodes during the surgery.

Usually, the bowel can be joined together again. But if this isn't possible, the end of the bowel will be brought out to the skin of the abdominal wall. This opening is called a stoma and the procedure is known as an ileostomy. A bag is worn over the stoma to collect bowel motions. The ileostomy will usually be temporary, and a further operation to rejoin the bowel can be done a few months later. The ileostomy is rarely permanent.

If the cancer is large and has caused a blockage in the small bowel, it is sometimes possible to bypass the tumour. This can help relieve the symptoms, even if it's not possible to completely remove the tumour. Your doctors will explain the aim of operation to you  before your surgery. They can answer any questions you have.

Sometimes the surgeon may not know exactly what they will do until during the operation.

After a major operation, you may have to stay in an intensive care ward for a couple of days before being moved back to a general ward.

When part of the small bowel has been removed or bypassed, you may need to have a special diet, supplements or medicines. This will depend on the extent of the surgery. This may help you digest and absorb food. Your doctor or nurse will explain this to you.

The stoma care nurse at the hospital will help you look after the stoma for the first few days. They can give you support and information on caring for your stoma when you go home. Our cancer support specialists  can give you more information about having an ileostomy.

Radiotherapy for small bowel cancer

Radiotherapy is the use of high-energy rays to destroy cancer cells, while doing as little harm as possible to normal cells.

Radiotherapy is not often used to treat small bowel cancers. But for some people, it may be used after surgery or in combination with chemotherapy (chemoradiation).

Chemotherapy for small bowel cancer

Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. Chemotherapy may occasionally be used to treat cancer of the small bowel, either in combination with radiotherapy or surgery, or on its own.

Fluorouracil (5FU), capecitabine, oxaliplatin (Eloxatin®) and irinotecan (Campto®) are the drugs most commonly used. Chemotherapy is not always suitable. Its effectiveness in treating small bowel cancer is still being researched.


After your treatment has finished, you’ll have regular check-ups, tests and scans. These appointments are a good opportunity to talk to your doctor about any worries or problems you have.

Many people find they get very anxious before appointments. This is natural. It can help to get support from family, friends, your specialist nurse or one of the organisations listed on our database. You can also talk things over with one of our cancer support specialists on 0808 808 00 00.

Research – clinical trials

Cancer research trials are carried out to try to find new and better treatments for cancer. Trials that are carried out on patients are known as clinical trials.

Trials are the only reliable way to find out if a different type of surgery, chemotherapy, hormone therapy, radiotherapy or other treatment is better than what is available already.

You may be asked to take part in a research trial. If you choose to take part, you will be carefully monitored during and after the study. If you decide not to take part, your decision will be respected and you won’t have to give a reason. There will be no change in the way you’re treated by the hospital staff, and you’ll be offered the standard treatment for your situation.

Your feelings

You may have many different emotions, including anxiety, anger and fear. These are all normal reactions. They are part of the process that many people experience when dealing with cancer.

Everyone has their own way of coping with difficult situations. Some people find it helpful to talk to family or friends. Others may prefer to seek help from people outside their situation. Some people prefer to keep their feelings to themselves. There is no right or wrong way to cope, but help is there if you need it. Our cancer support specialists can give you information about counselling in your area.