More than 6,000 people in the UK develop stomach cancer, otherwise known as gastric cancer, every year. In the UK stomach cancer is fairly uncommon and the number of new patients each year has halved over the past 30 years. We look at the causes, symptoms, diagnosis and treatment options:
What is stomach cancer?
There are various types of stomach cancer. The most common type is adenocarcinoma which starts in the glandular cells of the lining of the stomach. Other types include squamous cell cancers, lymphomas, gastrointestinal stromal tumours and neuroendocrine tumours. Stomach cancer is very common in Japan, and the Japanese have developed an intensive and effective approach to screening for stomach cancer.
In the UK, screening is not currently available because it is not safe or cost-effective.
What causes stomach cancer?
The causes of stomach cancer remain unclear.
Stomach cancer is more common in men than women, and its peak age range is between 40 and 60 years old. Possible risk factors include the following:
- Being overweight
- Being blood group A
- Having persistent infection with the Helicobacter pylori bacteria
Certain stomach conditions such as atrophic gastritis and pernicious anaemia can change the lining of the stomach, and may also be associated with an increased risk of stomach cancer.
While eating lots of fruit and vegetables may reduce the risk of stomach cancer, foods that have been pickled or salted appear to increase the risk.
For a small number of patients they have inherited a cancer gene that increases their risk of stomach cancer.
What are the symptoms of stomach cancer?
There are a number of symptoms which may indicate something is amiss, including the following:
• Digestion issues
Stomach cancer can cause symptoms such as acid reflux, heartburn and indigestion, but it is important to realise that this is a rare cause of these common symptoms.
• Appetite concerns
Other symptoms may include general fatigue, altered taste, nausea and reduced appetite.
Some patients also experience the feeling of being 'full up' or bloated sooner than usual after eating. Excessive belching can also be a symptom.
• Weight loss
Unexplained weight loss may also be associated with stomach cancer.
• Pain and discomfort
Patients may also experience a sensation of vague discomfort or even pain if the tumour grows through the stomach wall.
• Abdominal lump
Slim patients may become aware of a lump in the upper part of the abdomen just below the lower end of the breastbone.
Sometimes tumours can cause obstruction to the outlet of the stomach, which causes vomiting of large volumes of undigested food long after eating.
• Internal bleeding
There may be internal bleeding appearing as blood in the vomit, or black, tar-like, faeces, or the bleeding may be so slight as to pass undetected, If this is the case people may see a doctor because they are tired and pale and are then found to be anaemic.
Stomach cancer can grow slowly and in this case symptoms may only develop once the disease has spread beyond the stomach, for example to the liver. In this case, the symptoms would be those of cancer involving the liver. If you have concerns about any of these symptoms you should discuss these with your doctor.
How is stomach cancer diagnosed?
There are two main investigations for cancer of the stomach:
- A Barium meal: which involves swallowing a white, chalky liquid and having a series of X-ray pictures taken of the stomach area in a procedure called gastroscopy.
- A gastroscopy: during which the inside of the stomach is examined using a camera attached to a flexible tube. A biopsy from the tumour may be taken during this procedure.
How is stomach cancer staged?
Staging is a tool used to determine the extent of the disease as well as the most suitable treatment options. It also gives an indication of prognosis or survival.
To stage stomach cancer, the main investigation used is a CT or computerised tomography scan, which provides fine detail of your internal organs and allows your doctor to check the rest of your body for evidence of cancer spread.
Sometimes, a different type of gastroscopy called an endoscopic ultrasound is performed after the tumour has been diagnosed. An endoscopic ultrasound is carried out in the same way as a gastroscopy, but with the addition of a special ultrasound probe on the tip of the gastroscope. This allows your doctor to determine the depth of invasion of the tumour as well as evidence of spread outside of the stomach.
Some patients need to have other investigations such as a PET scan which measures the activity of any cancer cells in the body, or laparascopy, which is a type of exploratory surgery to look at the outside of the stomach and the nearby organs.
How is stomach cancer treated?
Decisions on the most appropriate treatment vary for each patient and may be influenced by factors including the stage of the cancer, other medical problems and someone's general health.
Surgery is an important treatment for early stomach cancer, and there are various types of operations performed (and may include removing part, or all of the stomach). The cure rate after surgery is about 30 per cent.
Chemotherapy, sometimes combined with radiotherapy, can be highly effective against some forms of stomach cancer and may help convert an inoperable tumour into an operable one. Chemotherapy may also be used to reduce or control symptoms in patients with advanced cancer. However, chemotherapy does have various side effects, some of which can be quite toxic. Radiotherapy can also be used to treat some of the symptoms caused by stomach cancer.
What is the stomach cancer outlook?
Stomach cancer prognosis is still quite poor, mainly because the disease isn't detected until quite late in its course.Statistics from Cancer Research UK indicate a five year survival rate of only 17.6 per cent.
Earlier detection will save lives, and new ways of assessing, particularly in those at high risk, will hopefully improve outcome.
Last updated: 16-10-19