Successful treatment of pancreatic cancer depends on early diagnosis. Various tests can help doctors rule out cancer or decide if further tests are needed.
If a person has symptoms that may be due to pancreatic cancer, doctors may recommend various diagnostic tests. This article explains how doctors diagnose pancreatic cancer. It describes the main diagnostic tests and what the results may mean.
How do doctors test for pancreatic cancer?
Pancreatic cancer can be difficult to detect in the early stages. Many people have no symptoms until the cancer has grown large or spread to other areas.
There are no routine screening tests for pancreatic cancer because experts do not believe screening reduces deaths. If a person has symptoms of pancreatic cancer, they should see a doctor. Doctors will likely recommend a series of tests to help determine the cause of a person’s symptoms. The following sections explain the main diagnostic tests.
Medical background
Asking about a person’s medical history is essential to help the doctor understand the risk of pancreatic cancer to which they are exposed. Doctors also inquire about the medical histories of family members, as the fact that a relative has had pancreatic cancer can increase the risk of developing this disease. Doctors also ask about the person’s current lifestyle and symptoms.
Physical examination
The doctor performs a physical examination to check for signs of cancer. If he notices the following signs, he can request additional examinations:
swelling of the liver or gallbladder
whites of the eyes tinged with yellow
yellowing of the skin, or jaundice
Learn what you can expect from a physical exam.
Imaging exams
Imaging tests provide visual images of a person’s internal organs and tissues. They can help doctors:
identify suspicious areas that could be cancers
see how far the cancer has spread
determine the effectiveness of the treatment
A radiologist is responsible for interpreting the results of an imaging test. He discusses the results with a doctor, possibly an oncologist, who then contacts the person concerned to inform him of the results.
Doctors may use the following tests to diagnose pancreatic cancer:
Computed tomography (CT scan)
CT scans take images of a person’s body in cross-section and clearly show the pancreas. These types of scans can also show if tumors have spread to other areas of the body, such as lymph nodes. If a doctor suspects pancreatic cancer, they may order a type of CT scan called a CT pancreas protocol scan. This test allows doctors to observe the activity of the pancreas using an injectable liquid.
Magnetic Resonance Imaging (MRI)
Some doctors prefer CT scans to look at the pancreas, but MRIs can also be helpful. These exams use radio waves to create images of internal organs.
There are two types of MRI:
MR Angiography (MRA): This scan specifically examines blood vessels using an injectable dye. It helps determine if a tumor is blocking part of the pancreas.
MR cholangiopancreatography (MRCP): This scan allows doctors to examine the pancreatic and bile ducts in the liver.
Ultrasound
Ultrasounds are useful for initial examinations of the abdomen because they do not emit radiation. Endoscopic ultrasound is the most accurate type of ultrasound. A doctor inserts an endoscope into the digestive tract to examine it and possibly take a tissue sample, or biopsy. An endoscope is a thin, flexible tube with one end fitted with a light and a lens.
Positron emission tomography (PET)
Positron emission tomography involves injecting a radioactive form of sugar into a vein. This substance, which is safe in small doses, accumulates in cancerous tumors and highlights any mass present in the body. This type of scan is useful for investigating cases where the cancer has spread to other parts of the body. In general, the results of a PET scan are available within a few days.
Blood tests
Doctors use several blood tests to help diagnose pancreatic cancer:
Tumor markers: These substances, including CA 19-9 and carcinoembryonic antigen, are present in the blood of people with cancer. However, their presence is not definitive enough to be the sole reason for the diagnosis, so further testing is needed.
Liver function tests: Jaundice and yellowing of the eyes can be symptoms of pancreatic cancer. Blood tests to assess levels of bilirubin, a substance produced by the liver, help doctors determine whether a person’s jaundice is the result of obstruction by a tumor or another condition.
The biopsy
A biopsy is the most accurate way to determine if a lump is cancerous. Doctors take a small sample of the lump and send it to a lab for analysis.
There are three main types of biopsies:
Percutaneous biopsy: A doctor inserts a thin, hollow needle into the skin of the abdomen to take a sample of tumor from the pancreas. It uses ultrasound or CT scan images to guide the needle to the right place.
Surgical biopsy: This type of biopsy is less common. Most often, keyhole surgery, or laparoscopy, allows the doctor to examine other areas of the abdomen to check if the cancer has spread.
Endoscopic biopsy: As described above, doctors use a thin, flexible endoscope to examine the digestive tract and remove a small sample of tumor tissue.
The doctor sends the biopsy sample to a lab, where a pathologist examines it under a microscope. The pathologist can:
determine if a lump is cancerous
determine the probable cause of the cancer
look for genetic causes, as this can help determine the best course of treatment.
Why can doctors recommend genetic counseling and testing?
Specific genes can make a person more likely to develop pancreatic cancer. BRCA mutations are genetic mutations that can occur in any cell in the body. Screening for these mutations can help lead to more effective treatments for people diagnosed with pancreatic cancer. If a person tests positive for specific genetic mutations, other family members may wish to consider genetic counseling and testing.
Résumé
Imaging tests, blood tests, biopsies, and genetic tests are essential to understanding the diagnosis of pancreatic cancer. These tests can either rule out a diagnosis of cancer or help determine the best course of treatment if a person has pancreatic cancer.