Stomach cancer

Peer reviewed by Dr Ian Arnott, Consultant Gastroenterologist
Next review due March 2019

Stomach cancer, also known as gastric cancer, is a tumour (lump) that’s created when cells in your stomach grow in an abnormal and uncontrolled way. About 5,600 people are diagnosed with stomach cancer in the UK each year – this number has been decreasing over the years. It mostly affects people over 55 and is more common in men.

About stomach cancer

Your stomach is a muscular bag in your abdomen (tummy), and its job is to break down the food you eat. The lining of your stomach produces a strong acid to help break down food. Stomach cancer can often develop in this lining or in your stomach wall.

If you don't get treatment for stomach cancer, it can spread to other parts of your body or organs, such as your liver. The spread of cancer through the body is called metastasis.

Image showing the digestive system

Types of stomach cancer

About nine in 10 stomach cancers are a type called adenocarcinoma. This starts in the lining of your stomach, in cells that produce stomach juices.

Other, rarer, types of stomach cancer include:

  • gastrointestinal stromal tumours (GIST), where the cancer starts in what’s called connective tissue – an example is your stomach wall
  • lymphomas, where the cancer starts in your lymphatic system – the tissues and organs that are involved in fighting infection and disease
  • carcinoid tumours, where the cancer starts in your system that produces hormones

Symptoms of stomach cancer

Symptoms of stomach cancer can include:

  • pain in your abdomen that might feel like indigestion
  • losing a lot of weight
  • feeling bloated
  • losing your appetite
  • difficulty swallowing
  • feeling sick or vomiting – you may vomit blood
  • blood in your faeces (stools), which can look black
  • a swelling or lump in your stomach

It’s not unusual to get some of these symptoms from time to time, such as indigestion. But if you have stomach cancer, they will last a long time. If this happens, contact your GP.

Diagnosis of stomach cancer

Your GP will ask about your symptoms and examine you. They’ll also ask you about your medical history. Your GP may give you a blood test, which will assess your general health.

Your GP may refer you to see a gastroenterologist – a doctor who specialises in conditions that affect the digestive system.

You might need to have some more tests, which could include the following.

  • Gastroscopy and biopsy. This is a procedure to look inside your stomach. Your doctor will use a narrow, flexible, tube-like telescopic camera called an endoscope to do this. They may remove a small sample of tissue from your stomach at the same time. This is called a biopsy. They’ll send this sample to a laboratory to see if it’s cancerous.
  • Barium swallow and meal. If you aren’t able to have a gastroscopy, you might have this test. In the test, you’ll be asked to swallow a liquid that contains barium (a substance which shows up on X-rays). X-ray images of your stomach will show any unusual growths more clearly.

If you're found to have stomach cancer, you may need to have other tests to find out how advanced it is. This process is known as staging. See Related information to find out more about this.

Treatment of stomach cancer

Your treatment will depend on the type of stomach cancer you have, and how far it’s spread. Your doctor will discuss what your options are.


Surgery involves removing the cancerous tissue from your stomach, usually along with a small amount of the surrounding healthy tissue.

You may have a partial gastrectomy, which means that your surgeon will remove part of your stomach. Or you may have a total gastrectomy and they will remove all of your stomach. Your surgeon may also remove the lymph nodes around your stomach to check whether the cancer has spread to them. Lymph nodes are lumps of tissue found throughout your body that contain white blood cells, and help to fight infections.

You might be able to have keyhole (laparoscopic) surgery rather than open surgery. This means your surgeon will make several smaller cuts in your abdomen instead of one larger one. Ask your surgeon if this is an option for you.

You may need to have chemotherapy or radiotherapy after your operation to make sure all the cancer cells are killed.

Non-surgical treatment

You might need to have one of the following treatments, either as well as surgery, or on its own.

  • Chemotherapy. This uses medicines to kill cancer cells. You may have intravenous chemotherapy or you may take the medicine as tablets or capsules. Intravenous chemotherapy involves having a tube (drip) inserted into a vein in your arm or hand and the medicine going directly into your bloodstream.
  • Biological therapy. This uses a substance that stimulates your body to attack or control the growth of cancer cells. If your stomach cancer has spread, you may be offered a medicine called trastuzumab (Herceptin) alongside chemotherapy. It works by targeting cancer cells that have a particular protein on their surface. Trastuzumab isn’t suitable for everyone – ask your doctor if it's an option for you.
  • Radiotherapy. This uses radiation to destroy cancer cells and may be used alongside chemotherapy.

You might be asked to be part of a clinical trial of a new treatment that may show promise for treating stomach cancer. Ask your doctor for more information.

Causes of stomach cancer

Doctors don’t yet know the exact reasons why some people develop stomach cancer. But you're more likely to develop it if you:

  • are over 55
  • are a man (men are around twice as likely to develop stomach cancer as women)
  • get infected with the bacterium Helicobacter pylori
  • have acid reflux, also known as gastro-oesophageal reflux disease (GORD)
  • have pernicious anaemia – where your body doesn't absorb enough vitamin B12 from your diet
  • have a family history of stomach cancer
  • smoke
  • are overweight
  • eat too much salt or preserved foods, such as smoked or pickled foods
  • don't eat many fruit and vegetables

Prevention of stomach cancer

If you make some changes to your lifestyle, it may reduce your risk of getting stomach cancer. Here are some things you can try. 

  • Cut down on processed foods and eat a fresh and balanced healthy diet that includes at least five portions of fruit and vegetables a day.
  • Don't smoke.
  • Don’t drink too much alcohol.
  • Keep to a healthy weight.

For advice and tips on how to change your lifestyle, see Related information.

Frequently asked questions

  • This will depend on your individual circumstances. Your doctor will take into account your wishes, your general health, the type of cancer you have and how far it’s spread.

    If you’re diagnosed with stomach cancer early, it can be easier to treat. Surgery will be your main option to remove all of the cancer and reduce the risk of it spreading. Whenever possible, your surgeon will remove only part of your stomach rather than all of it, so you have fewer complications after your operation. They might offer you chemotherapy or radiotherapy before and after surgery, to increase the chance of your treatment being successful. 

    If your stomach cancer is diagnosed at a late stage, it may not be possible to cure it. Your treatment will focus on treating your symptoms. Ask your doctor for more information about what your treatment will involve.

    A multidisciplinary team of health professionals can help you to decide which treatment is best for you. This team will consist of a range of health professionals including a surgeon, oncologist (a doctor who specialises in cancer) and cancer nurses.

  • Gastric dumping syndrome is a side-effect of stomach surgery. It's caused by the sudden movement of food into your small bowel. This can cause unpleasant symptoms straight after you eat a meal, or a few hours later.

    Gastric dumping syndrome can start soon after you’ve had stomach surgery, but often settles down over the course of a few months. 

    Symptoms of gastric dumping syndrome include:

    • feeling dizzy
    • a fast heart rate (palpitations)
    • feeling faint
    • pain in your abdomen (tummy) or feeling bloated
    • diarrhoea 

    Early gastric dumping syndrome happens because food moves out of your stomach into your small bowel more quickly than before your surgery. This can give you symptoms within 15 minutes to an hour after eating.

    Late gastric dumping syndrome happens one to three hours after you eat. When sugary and starchy food passes from your stomach into your small bowel it causes a sudden rise in your blood sugar level. Your body responds by releasing a hormone called insulin. The levels of insulin continue to rise even when the level of sugar in your blood starts to fall. This is what causes the symptoms. 

    You can ease the symptoms of gastric dumping syndrome by:

    • eating smaller meals more often (have about six small meals a day)
    • resting for 30 minutes after meals by sitting or lying down
    • cutting down on processed carbohydrates and cutting out sugary foods and milk altogether as they can make your symptoms worse
    • having drinks between meals rather than during them
  • Treatment for stomach cancer often means having an operation to remove part, or all, of your stomach. This means that in the first day or so after your operation, you won’t be able to eat or drink. To help you get the nutrients your body needs, you may be fed through a tube that’s put straight into your bowel.

    You’ll usually be able to start eating small amounts of food a few days after your operation. As you recover, you may feel full after small amounts of food. Some nutrients, including calcium, iron, vitamin D and vitamin B12, are usually absorbed through your stomach. If you’ve had part, or all, of your stomach removed, your body may not get enough of these. So try to eat more foods that contain these nutrients. See our Related information on diet and nutrition to learn how. You may need to take supplements – your doctor may refer you to a dietitian for advice on what you need.

    If you’ve had your whole stomach removed, you’ll need to have injections of vitamin B12 for the rest of your life. If only part of your stomach was removed, you’ll need to have regular blood tests. These will check if you’re getting enough vitamin B12 and iron from your diet.

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Related information

Tools and calculators

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    • Gastric cancer. Medscape., updated 11 November 2015
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    • Having your operation for stomach cancer. Cancer Research UK., updated 13 February 2014
  • Reviewed by Rachael Mayfield-Blake, Freelance Health Editor, March 2016
    Peer reviewed by Dr Ian Arnott, Consultant Gastroenterologist
    Next review due March 2019

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