Stomach Cancer

Stomach cancer is one of the top ten leading cancer in Hong Kong, with around 1000 new cases annually.  The incidence rate of stomach cancer rises along with age but the number of young patient has increased significantly in recent years.

The early symptoms of stomach cancer are not obvious. Many patients consider them as stomach upset and take them lightly so that diagnosis and treatment are delayed. Therefore, more than half of the patients have their cancer already spread to other tissues and turned to advanced stage when they discover the illness and undergo treatment.

To prevent stomach cancer, you should start with your diet, eat more fresh fruits and vegetables and less preserved food. Remember to quit smoking and drinking. You should pay special attention if you have symptoms like persistent indigestion and loss of appetite.

(Special thanks to Dr. K M CHEUNG, Associate Consultant, Clinical Oncology, Queen Elizabeth Hospital, and Dr. Mary LAM, Associate Consultant, Clinical Oncology, Princess Margaret Hospital)

Gene mutation (change of the gene) of stomach tissues cells resulted in malignant transformation of cells. The etiology of stomach cancer is so far uncertain, but cancer formation could be hastened by H pylori and Epstein-Barr virus (EBV) infection.

Stomach is part of the digestive system. It secretes gastric acid to help digest and grinds large pieces of food into small ones. The food then enters the intestine for further digestion process by intestinal peristalsis.

When there is a mutation in stomach cells and develop into malignant tumour, it is called stomach cancer.


Many factors lead to stomach cancer. Research shows that helicobacter pylori (a kind of bacterium which survives in the stomach and duodenum) and Epstein-Barr virus infection may increase the chance of stomach cancer. If you fall in one of the following categories, you should pay special attention:

  • Sex: chance of stomach cancer for men is double of that of women.

  • Age: the older the age, the higher chance of stomach cancer. The chance is even higher after 50.

  • Diet: consumption of high-salted, pickled and smoked food will increase the danger of having stomach cancer.

  • Diseases: people who have stomach polyps, had gastrectomy (stomach removal surgery) or pernicious anaemia (anaemia resulted from deficiency of vitamin B) are more susceptible to stomach cancer.

  • Smoking: smokers are more likely to have stomach cancer than non-smokers.
  • Genetic: people whose immediate family members had stomach cancer are twice as likely to have stomach cancer than others

The general dietary recommendation to reduce the chance of cancer applies: 

More fresh fruits and vegetables:

  • Vegetables in brassicaceae (e.g. broccoli, Chinese cabbage, cauliflower, kale, etc.) contain anti-cancer substance which helps break down carcinogen (a substance that is capable of causing cancer) in the body;
  • Vegetables containing rich carotene (e.g. carrot, mango, papaya, etc.) help enhance body immunity and directly lower the chance of cancer.
  • Food containing rich vitamin C (e.g. orange, grapefruit, strawberry, etc.) has anti-oxidation function, which can lower the chance of stomach cancer.
Less high salt food:
  • Pickled and smoked food (e.g. Chinese sausage, salted egg, sausage, ham, bacon, salted fish, etc.) contain carcinogenic compounds formed in the production.
  • Deep-fried food. Free radicals are produced during deep-frying which reduces the oxygen content of tissues in the body causing damage.
Be aware of personal hygiene:
  • Wash your hands frequently and avoid touching excrement or vomit, preventing infection of helicobacter pylori (a bacteria inhabit various areas of the stomach and duodenum).

Regular checkups:
If you are over 40 and you have a family history of stomach cancer, you are advised to have regular upper endoscopy (an endoscopy of the gullet and stomach).



If the following symptoms occur, it may be stomach cancer, but it may also be other more common illness, e.g. gastritis (inflammation of the stomach), stomach or duodenal (top of the small intestine) ulcer. If you have suspected symptoms, you should consult your family doctor as soon as possible: 

  • persistent indigestion, loss of appetite
  • unexplained weight loss
  • swelling of abdomen
  • feeling bloated after eating, especially after small meals
  • vomit or blood in vomitus
  • blood in stools, or black stools
  • anemia, fatigue, weakness


If you have the above symptoms, you should consult your family doctor as soon as possible and undergo tests. Tests for stomach cancer include: 相片

(1) Upper Endoscopy

During endoscopy, doctor uses a thin, flexible tube with a camera and pass it into the mouth, esophagus and stomach to look at the digestive tract. Suspicious area will be examined. Tissues samples might be taken for further microscopic checkup. The diameter of endoscope is actually thinner than a finger. The examination takes around 5 to 20 minutes. After procedure, patients may feel mild throat discomfort and bloating.

(2) Abdominal ultrasound and computer tomography (CT) scan:

These examinations help diagnose the stage of stomach cancer and the sign of spread accurately.



If the patient is diagnosed of stomach cancer, doctor will suggest the following treatments to patient:

Surgery to remove stomach cancer

If the cancer is diagnosed early, it could be removed by surgery.  Depending on condition, a portion of or the entire stomach might need to be removed with the tumour. Surrounding tissues, lymph nodes around stomach, or sometimes the neighboring organs may also be removed.

In a very early stage of stomach cancer, the cure rate by stomach removal surgery can be as high as 90%.


Radiotherapy uses high-powered radiation beams to destroy cancer cells. It may be used together with chemotherapy after surgery to reduce recurrence and enhance the survival rate after surgery.


Chemotherapy uses anti-cancer drugs to kill cancer cells and stop them from growing and dividing. There are drugs for oral administration and intravenous infusion (infusion of drugs into the bloodstream through a vein), mainly after surgery treatment, aiming at preventing recurrence and enhancing the survival rate after surgery. Chemotherapy can also be used as palliative treatment for relieving symptoms and prolonging life.

Targeted therapy and immunotherapy

Some patients may also benefit from target therapy or immunotherapy. In suitable cases, they could be used to enhance the effect of chemotherapy or to be used after chemotherapy to stabilize cancer for a certain period of time when chemotherapy no longer works. Patients may have to pay for these treatments. 


The possible complications of stomach cancer patient are as follows:
Tumour complications:

  • Gastrointestinal bleeding: dizziness, palpitations, black tar-looking stool, coffee ground-looking vomit.

  • Tumour may cause obstruction at the end of stomach. When it is blocked by tumour, food cannot pass down to bowel, causing bloating, upper abdominal pain and vomiting.

  • In some cases, cancer could spread around bile duct. The patient will have symptoms of yellowing of eyes and skin and grey stool. 

  • In some cases, stomach tumour could perforate and lead to peritonitis (inflammation of abdominal cavity).  This could be life-threatening.
Surgical complications:
  • There may be leakage or inflammation at the connection between esophagus and bowels after stomach removal surgery. Patient could experience severe abdominal pain, vomiting and fever. They are advised to see doctor immediately.

  • Patients may experience discomfort after meals, including diarrhea, dizziness, low blood pressure and vomiting. It is because of the reaction of the food passing too quickly to small intestine after the removal of part of or the entire stomach. They are advised to take frequent small meals.

After removal of stomach, patient needs to make some adjustments in diet:

  • Frequent small meals, e.g. six meals a day and avoid eating too much, otherwise there may be vomit, diarrhea, dizziness and low blood pressure. Avoid any drinks during and after meals to prolong the time that the food stays in the stomach to help absorption.

  • Choose food which is easy to digest

  • Get used to chewing food slowly and thoroughly

  • Take a rest after meals to prevent indigestion

  • Choose foods with abundant vitamin B12 (e.g. liver, meat, fish and milk). Some patients need regular injection of vitamin B12 after stomach removal surgery.
  • Avoid raw or undercooked meat, poultry, eggs, seafood, raw or unpasteurized dairy products, and ready-to-eat raw vegetables.
Back To Top
Local and Overseas Supporting Organisations
Back To Top
Related Documents
Back To Top
Related Audio
Back To Top
Related Video
Back To Top
Back To Top