Blood test to diagnose stomach cancer

The article was consulted with Specialist Doctor I Dong Xuan Ha - Gastroenterologist - Department of Medical Examination & Internal Medicine - Vinmec Ha Long International General Hospital.

Blood tests may be used to screen for stomach cancer. Besides the indicators of blood cells, electrolytes, indicators of liver and kidney function, blood tests for cancer markers are considered to be significant in early diagnosis of stomach cancer.

1.1. Blood tests for cancer markers Cancer markers are chemicals that can appear in the blood in some types of cancer. Therefore, this type of blood test may be ordered to screen for stomach cancer. For example, carcinoembryonic antigens (CEA) and CA 19-9 antigens may be elevated in gastric cancer, as well as in other cancers.
Quantification of Pepsinogen I and II, and the ratio between them, are also used for risk assessment and early detection of gastric cancer in patients at risk.
However, some people with stomach cancer do not have elevated levels of cancer markers or have them with other conditions other than cancer. In the case of increased levels of cancer markers, the patient still needs to perform other tests to support an accurate diagnosis of the current health condition.
1.2. Complete blood count (FBC) A complete blood count (FBC) test is used to check the number of each type of blood cell (red blood cells, white blood cells, and platelets). Red blood cells are responsible for carrying oxygen throughout the body. If your red blood cell count is low, you're most likely anemic, especially if you're tired, short of breath, or dizzy. White blood cells play a role in fighting infections. There are different types of white blood cells such as neutrophils and lymphocytes. Platelets are responsible for blood clotting. A low platelet count can cause abnormal bleeding, such as bleeding gums and nosebleeds. A blood count test does not have a perfectly accurate normal range. Test results can vary slightly between laboratories and also between men and women.
Table diagram showing normal blood count values ​​of men and women

1.3. Urea and electrolytes Urea is a waste product that is removed from the blood by the kidneys and excreted in the urine. The blood urea nitrogen test helps assess how well the kidneys are working. Electrolytes such as sodium, potassium, chloride, bicarbonate are also taken to determine the level of electrolyte balance in the body.
1.4. Liver function tests (LFTs) Liver function tests (LFTs) help check how well the liver is working by determining the levels of enzymes and proteins made or eliminated by the liver, they include:
Alanine aminotransferase (ALT) Aspartate aminotransferase (AST) Alkaline Phosphatase (ALP) Gamma-glutamyl transferase (Gamma GT) Total, direct, indirect bilirubin. Blood coagulation and albumin tests. These indicators help identify conditions such as liver failure, liver cell damage, blockage in the liver or bile ducts, and alcohol abuse. The test can also help determine bilirubin levels, which are elevated when you have liver or gallbladder problems. High levels of bilirubin in the body can cause yellowing of the skin and eyes.
LFTs can also measure levels of albumin, a protein in the blood. Albumin levels are often low in certain types of cancer, malnutrition, or poor diet.

Blood tests are used to:
Check general health including liver and kidney function Check blood cell counts Help diagnose various medical conditions Blood samples will be sent to the laboratory tests to check the number of blood cells, different chemicals, and proteins in the blood. From there, help your doctor detect abnormalities in your body.

For most blood tests, you can eat and drink normally before the test. However, for some blood tests, your doctor will tell you to fast for a certain amount of time before the test.

You may have your blood drawn in a sitting or lying position. The nurse will choose the best vein to draw blood from, mainly in the arm or hand. In case of fear of needles, feeling unwell at the sight of blood, allergic to bandages, etc. talk to your healthcare provider to get the best care.
Once the vein has been selected, the nurse will place a bandage around the arm above the area to be sampled. You may need to make a fist to find the vein more easily.
The nurse will clean the skin, insert the needle into the vein and draw the blood according to the required amount, then withdraw the tourniquet, withdraw the needle, and put a bandage on the injection area. After the needle is withdrawn, blood will be filled into the test tubes.
If you are afraid of blood, you may need to look away while drawing blood. Tell your doctor or nurse if you feel unwell.
After the blood is drawn, ask for the time to wait for the results. Some tests only need to be done in a short time, while others take several weeks.

A blood test is a safe type of test. However, after a blood draw you may experience the following problems:
Bleeding and bruising can be reduced by pressing firmly on the injection site after the needle is withdrawn Feels mild pain, which usually lasts for a few minutes Swelling arm, ask your doctor for advice on how to reduce swelling Dizziness or fainting, tell your healthcare provider if you have this feeling Infection, this is very rare Blood tests may be used to screen stomach cancer, among many other diseases. Therefore, in order to make an accurate diagnosis, the patient must follow the doctor's instructions.

Reference source: cancerresearchuk.org