Stomach cancer

The stomach is a stretchy, muscular bag that stores food and helps break it down through digestion. It is in the upper left-hand side of the tummy area (abdomen).

Cancer can develop in the stomach. This is called stomach cancer or sometimes gastric cancer. Stomach cancer may spread to other parts of the body and can spread to lymph nodes close to the stomach.

The risk of developing stomach cancer increases as you get older. Over half of people (50%) diagnosed with stomach cancer are aged 75 or older.

Knowing the type of stomach cancer helps your cancer doctor plan your treatment.

This information is about adenocarcinoma, which is the most common type of stomach cancer. More than 9 in 10 stomach cancers (95%) are adenocarcinoma. Adenocarcinoma starts in the glandular cells of the stomach lining.

Less common cancers that can start in the stomach include:

• soft tissue sarcomas, including gastrointestinal stromal tumours (GISTs)
• lymphomas, such as mucosa-associated lymphoid tissue (MALT) lymphomas
• neuroendocrine tumours (also known as NETs).

The tests and treatments for these types of stomach cancer are different from the ones we describe in this information.

Certain things can increase the chance of developing stomach cancer. These are called risk factors. Having a risk factor does not mean you will definitely get stomach cancer. Or if you do not have any risk factors, you may still be diagnosed with stomach cancer. We do not yet know why only some people who have risk factors develop stomach cancer.

Stomach cancer is not infectious and cannot be passed from one person to another. 

We have more information about the causes and risk factors of stomach cancer.

Your cancer doctor needs information about the cancer to advise you on the best treatment for you. This includes the cancer’s:

• stage, which describes the cancer and whether it has spread
• grade, which gives an idea of how quickly the cancer might grow and spread.

Your cancer doctor can use the results of your tests to try to identify the stage of the cancer. They will do this before your treatment is planned to help decide the best treatment for you. But they may not know the exact stage of the cancer until it has been removed with surgery.

We have more information about staging and grading.

After your treatment has finished, you will have regular follow-up appointments. You will usually talk with someone from your healthcare team at the appointment. This may be your surgeon, cancer doctor, specialist nurse or another health professional.

If you have any problems or new symptoms between appointments, tell your cancer doctor or specialist nurse as soon as possible.

You may get anxious between appointments. This is natural. It may help to get support from family, friends or a support organisation.

Macmillan is also here to support you. If you would like to talk, you can:

• Call the Macmillan Support Line for free on 0808 808 00 00.
• Chat to our specialists online.
• Visit our stomach cancer forum to talk with people who have been affected by stomach cancer, share your experience, and ask an expert your questions.

It can take a few months to recover from treatment for stomach cancer. You will usually have a soft diet while you are still in hospital, and normally be advised to keep to this diet for a few weeks. It will help to eat small amounts more often. Gradually, you will be able to start eating solid foods again. It may take up to a year to adjust to the changes in your digestive system.

After an operation to remove the stomach or part of the oesophagus, food can travel more quickly through the digestive system. This can cause symptoms called dumping syndrome.

We have more information and advice about eating after treatment for stomach cancer and about dumping syndrome.

Even if you already have a healthy lifestyle, you may choose to make some positive lifestyle changes after treatment.

Making small changes such as keeping active can improve your health and wellbeing and help your body recover.