Pancreatic cancer is cancer that starts in the pancreas. The pancreas makes enzymes and hormones vital for promoting digestion and regulating blood sugar.
Specific biomarkers, called tumor markers, can be found in the blood of people with pancreatic cancer. These markers can not only help doctors diagnose pancreatic cancer, but they can also indicate whether a treatment is working.
In this article, we review common pancreatic cancer tumor markers along with their uses and their accuracy. We also look at other methods used to diagnose pancreatic cancer.
A tumor marker is something that’s made by cancer cells or that’s produced by your body in response to cancer. Tumor markers are typically proteins, but they can also be other substances or genetic changes.
How tumor markers are used
The measurement of tumor markers has several uses for cancer. These can include:
- helping to diagnose a cancer
- determining if certain types of treatment, such as targeted therapy, can be used for a cancer
- finding out if a cancer treatment is effective
- estimating the outlook of a cancer
- detecting if cancer has come back (recurred) or spread (metastasized)
Common tumor markers for pancreatic cancer
There are a couple of tumor markers most commonly in use for pancreatic cancer. These are:
- CA19-9, a protein made by cancer cells
- carcinoembryonic antigen (CEA), a protein that’s normally present in the body of a developing fetus, but can also indicate cancer in adults
When pancreatic cancer is present, both proteins may appear at higher levels in the blood. They can be used to help diagnose pancreatic cancer and also to see how well pancreatic cancer treatments are working.
Measurement of levels of CA19-9 and CEA involves a blood sample collected from a vein in your arm. The table below shows the typical and high ranges for both tumor markers.
|0 to 37 units per milliliter
|greater than 37 units per milliliter
|less than or equal to 3 micrograms per liter (Smoking can increase this value to less than 5 micrograms per liter)
|higher than 5 micrograms per liter
While tumor markers can be useful for pancreatic cancer, they’re not always accurate.
For example, some people with pancreatic cancer may not have elevated CA19-9 or CEA. Some
In other situations, another health condition may be causing elevated CA19-9 or CEA levels.
Because of these factors, additional tests are always needed. These can include:
- imaging tests
- other blood tests
Research into CA19-9 and CEA for pancreatic cancer
In addition to testing for tumor markers, there are several other tests that doctors can use to diagnose pancreatic cancer. These include:
Imaging tests help your doctor get a look inside of your body to find areas that may be cancerous. They may use many imaging tests for pancreatic cancer, including:
- CT scan. A CT scan uses X-rays to make cross-sectional images of your abdomen. A special type of CT scan called a multiphase CT scan is often used when pancreatic cancer is suspected.
- MRI scan. MRI scans use radio waves and strong magnets to make images of the inside of your body.
- PET scan. A PET scan uses a radioactive dye that localizes to cancer cells. A specific type of camera then detects concentrations of this dye in the body. PET scans can also be helpful to see if a cancer has spread.
- Ultrasound. An ultrasound utilizes sound waves to produce images. A type of ultrasound called an endoscopic ultrasound is typically more helpful than a standard ultrasound for diagnosing pancreatic cancer.
- Cholangiopancreatography. A cholangiopancreatography can look for tumors blocking pancreatic or bile ducts. They’re often done using an endoscope and X-rays.
In addition to blood tests for tumor markers, a doctor may order other blood tests if they suspect pancreatic cancer. These include:
- liver function tests to check how well your liver is working
- complete blood count to measure the levels of different kinds of blood cells
- blood chemistry panel to get an idea of how your kidneys are functioning as well as the levels of things like sugars, fats, and electrolytes in your blood
A biopsy involves the collection of a small tissue sample from the tumor site. This sample is analyzed in a lab to see if it contains cancer cells.
If cancer is found, other tests can also be done on the biopsy sample to look for certain biomarkers or genetic changes. The presence or absence of these things can help to inform which type of treatment is recommended.
There are several risk factors for pancreatic cancer, including:
- having a family history of pancreatic cancer
- having certain inherited genetic syndromes like:
- Peutz-Jeghers syndrome
- inherited breast and ovarian cancer syndrome (mutations in the BRCA1 or BRCA2 genes)
- being at an older age
- being assigned male at birth
- being Black, although the exact reason for this increased risk remains unknown, research suggests it may be due to inequities in healthcare, along with environmental and socioeconomic factors.
- having certain health conditions, including:
Screening for high risk groups
The American Gastroenterological Association (AGA) recommends that people at an increased risk due to a family history of pancreatic cancer or an inherited genetic syndrome consider screening for pancreatic cancer.
According to the AGA recommendations, the age to start screening depends on an individual’s situation. For example, it may begin as young as age 35 for people with Peutz-Jeghers syndrome or at age 50 for people with a family history of pancreatic cancer.
Screening for pancreatic cancer involves the use of MRI and endoscopic ultrasound. Genetic testing may also be recommended as well.
Screening can typically take place every 12 months. However, if a doctor finds suspicious areas on or around the pancreas, they may reduce this interval, making screening more frequent.
Currently, screening of people with an average risk of pancreatic cancer is not recommended.
What are the early symptoms of pancreatic cancer?
Early stage pancreatic cancer typically doesn’t cause any symptoms. This is why many pancreatic cancers aren’t found until they reach an advanced stage. When present, pancreatic cancer symptoms may include:
- abdominal pain
- reduced appetite
- unintended weight loss
- yellowing of the skin and eyes (jaundice)
- dark urine
- pale stool
- itchy skin
- nausea and vomiting
- blood clots, which often happen in the legs
- enlarged liver or gallbladder
- new-onset diabetes or worsening of existing diabetes
What is the one test that can accurately diagnose pancreatic cancer?
While other tests are very helpful in the diagnostic process, the only sure way to diagnose pancreatic cancer is by analyzing a biopsied tissue sample. This is because a sample of the affected area can be directly examined for the presence of cancer cells.
How common is pancreatic cancer?
According to the
Is pancreatic cancer curable if caught early?
Pancreatic cancer is difficult to catch early. Many people don’t begin to have symptoms until cancer has advanced. Further, because the pancreas is deeper in the body, smaller tumors may not be easily detected by imaging.
The outlook for pancreatic cancer does improve when it’s found early. According to the
Tumor markers are biomarkers made by cancer cells or produced by the body in response to cancer. The tumor markers commonly used for pancreatic cancer are CA19-9 and CEA.
While the results of blood tests for these biomarkers can provide a doctor with helpful information, further tests are always needed. These may include imaging tests, additional blood tests, and biopsy.
Pancreatic cancer screening can be done in people with a family history of pancreatic cancer or with certain inherited genetic syndromes. If either of these apply to you, talk with a doctor about how and when to get started with pancreatic cancer screening.