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What does a high level of the tumor marker Ca19-9 mean?



If the tumor marker CA19-9 is high

Before explaining tumor markers, the premise is that when cancer develops in the body, characteristic proteins and other substances are produced by cancer cells and cells that reacted to cancer cells, and increase in body fluids.

Tumor markers can test for these substances to determine the presence of cancer, the course of treatment, and whether the cancer has recurred or metastasized.

One of them is CA19-9. If CA19-9 is high, it can be elevated in benign diseases as well as in non-malignant diseases, but if it is much higher than the standard value, it is predicted that some abnormality is occurring.

Therefore, first consult your family physician at a medical institution.

What does the CA19-9 value represent in the first place?

CA19-9 represents a protein that is abundant in the digestive tract, including the pancreatic and bile ducts, bronchial glands, and endometrium.

What is the reference value and what is the danger level?

The reference value is 37 U/ml or less, and higher values are considered abnormal.

What happens if CA19-9 is high?

It is said that the standard value is 37 or below, 37 to 50 is mildly elevated, 50 to 100 is moderately elevated, and 100 or above is highly elevated.

Assuming cancer, the higher the value, the more serious the disease, and there is a possibility that the cancer has metastasized to other organs.

Therefore, immediate medical attention is required.

What is the probability of cancer with CA19-9? Are the numbers reliable?

There are data showing a positive rate of 80 to 90% for pancreatic, bile duct, and gallbladder cancer, and 30 to 50% for gastric and colorectal cancer, but it varies depending on the pathology and stage of the disease.

In addition, the positive rate is said to be about half for early-stage cancers and pancreatic cancers smaller than 2 cm, limiting its usefulness in diagnosis and screening. It should be noted that benign diseases such as pancreatitis with cholangitis, gastritis, hepatitis, and cirrhosis can also cause elevated levels as high as 100 U/mL.

What cancers develop when CA19-9 is high?

These include pancreatic cancer, bile duct cancer, gallbladder cancer, stomach cancer, colon cancer, liver cancer, ovarian cancer, breast cancer, uterine cancer, and lung cancer.

What should I do if my CA19-9 level is high?

First of all, we recommend that you undergo an examination at a medical institution.

In addition to blood tests, ultrasonography, gastrointestinal endoscopy, colonoscopy, CT, MRI, etc., if necessary, or an internal examination if a gynecological disorder is suspected, are also necessary for a thorough examination.

What causes CA19-9 to be high, and who is prone to it?

In addition to cancer, pancreatitis, hepatitis, cholelithiasis, uterine fibroids, ovarian cysts endometriosis, bronchiectasis, hepatitis, cirrhosis, streptococcal infection, and diabetes can cause CA19-9 levels to be high, so high levels do not necessarily mean that cancer such as pancreatic cancer, gallbladder cancer, and bile duct cancer are the only causes.

My CA19-9 level suddenly became high, why?

As an example, one of the symptoms of pancreatic cancer is an elevated blood sugar level. There is a case in which a patient with diabetes mellitus suddenly experienced poor blood glucose control, and upon investigation, pancreatic cancer was found, and the CA19-9 level suddenly became higher than it had been a year earlier. Since a sudden increase in CA19-9 level does not necessarily mean that the patient has cancer, a thorough examination is recommended.

What you can do yourself to bring the CA19-9 level to normal

If it is not cancer but diabetes, pancreatitis, hepatitis, etc., you can bring it close to normal by improving your lifestyle.

Treatment to normalize the CA19-9 level of tumor marker

If the disease is cancer, standard treatment (surgery, chemotherapy, radiation) or immunotherapy is used to reduce cancer cells.

If it is a benign disease, please ask your doctor for a treatment tailored to your disease.

What we recommend at HIC Clinic

In addition to conventional blood sampling for tumor markers such as CA19-9, CEA, AFP, PIVKA-II, PSA, CA72-4, SCC, NSE, Pro-GRP, and DUPAN-2, which are used in medical examinations and physical examinations, our clinic can examine more than 200 genes to determine precancerous conditions or the state one step before it. The results can be used for pre-cancerous or one-step-ahead conditions.

Recently, genetic abnormalities have been scored, and if five or more abnormal genes are found, PET-CT may detect early-stage cancer, and we are especially focusing on prevention.


Picture of 平畑 徹幸

平畑 徹幸

HICクリニック院長 医学博士

日本内科学会、日本抗加齢医学会、一般社団法人 日本アンチエイジング外科学会、膵臓病学会、日本遺伝子診療学会、日本人類遺伝子学会、アメリカ人類遺伝学会、A4M「米国抗加齢学会」
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