Stomach Cancer

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.

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 tumor, 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) 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 upper endoscopy (an endoscopy of the gullet and stomach) every year.

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
• rapid weight loss
• swelling of lower abdomen
• feeling bloated after eating
• vomit, even vomit blood
• 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：

(1) Upper Endoscopy Doctor puts an optical catheter looking endoscope into the stomach of the patient through the mouth and oesophagus to observe the lesion condition and take tissues samples from different parts for pathological examination. The diameter of endoscope is thinner than a finger. The examination, which usually takes 5 to 20 minutes, may cause mild discomfort in the throat and bloated of gas in upper abdomen. (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:

Stomach removal surgery

Stomach removal surgery is the most common treatment of stomach cancer. Doctor decides to remove a portion of or the entire stomach depending on the patient’s condition. During the surgery, doctor removes the tumor and the tissues and lymph nodes around. 

In general, if the lesion is only limited to mucosa and submucosa, the cure rate of stomach removal surgery can be as high as 90%.

Radiotherapy

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

Chemical anti-cancer drugs

Chemotherapy uses anti-cancer drugs to kill cancer cells and stop them from growing and dividing. There are drugs for oral administration and intravenous injection (injection 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. A minority of patients may also benefit from target therapy. 

The common complications of stomach cancer patient are as follow:

• Gastrointestinal bleeding：dizziness, palpitations, black tar-looking stool, coffee ground-looking vomit.
• Spread of stomach cancer to abdominal cavity will cause pressure to common bile duct. The patient has symptoms of yellow eye white and skin and grey stool. 
• Obstruction of pylorus, which is a sphincter structure at the end of stomach. When it is blocked by tumor, food cannot pass to duodenum through pylorus smoothly, causing upper abdominal pain and vomiting
• Tumor causes stomach perforation, which leads to peritonitis (inflammation of the membranes of the abdominal wall and organs).  This is fatal acute emergency having the symptom of abdominal pain.

There may be leakage in the anastomosis after stomach removal surgery. And patients may have symptoms such as vomit after meal, diarrhea, dizziness and low blood pressure. 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.

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

• Frequent small meals, e.g. 6 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
• Take a rest after meals to prevent indigestion
• Avoid anemia, be aware of the supplement of vitamin B12 (e.g. liver, meat, fish and milk). Some patients need regular injection of vitamin B12