Pancreatic Cancer Diagnosis
Several steps are involved in making a diagnosis of pancreatic cancer. The first thing your doctor will do is ask questions about your medical and family history, possible risk factors and symptoms. Answering these questions honestly and completely will help both you and your doctor during the diagnostic process.
A doctor will perform a physical examination and check your abdomen for tenderness, fluid buildup, enlargement of your gallbladder or liver, and masses. Your lymph nodes will be checked for tenderness and swelling, and any sign of jaundice will be noted. Your doctor also may order blood or urine tests, testing of stool samples or imaging tests.
No single blood test can be used to make a diagnosis of pancreatic cancer yet. When a person has pancreatic cancer, however, elevated levels of bilirubin or liver enzymes may be present.
Different tumor markers in the blood are used to detect and monitor many types of cancer. Tumor markers are substances, usually complex proteins, produced by tumor cells.
Two commercially available tumor marker tests are of use in patients with pancreatic cancer: cancer antigen 19-9 (CA 19-9) and carcinoembryonic antigen (CEA). These markers are not accurate enough to be used to screen healthy people or to make a diagnosis of pancreatic cancer. However, CA 19-9 and CEA are frequently used to track the progress of treatment in patients with pancreatic cancer. CA 19-9 is a substance found on the surface of certain types of cells and is shed by tumor cells, making it useful in following the course of cancer. The presence of the protein CEA may indicate cancer because elevations in CEA levels are not usually found in people who are healthy. CEA is not as useful as is CA 19-9 in pancreatic cancer testing.
Lustgarten-funded researchers at Johns Hopkins designed a blood test called CancerSEEK that can detect the presence of pancreatic cancer as part of a panel of eight common cancers: pancreas, ovary, liver, stomach, esophagus, colorectum, lung and breast. It can identify the presence of relatively early cancer, and can detect the organ of origin of the cancers. This test is an important breakthrough because these eight cancers account for more than 60% of cancer deaths. While further testing is needed, the goal is for CancerSEEK to be offered as part of routine medical checks.
If blood and urine test results show high levels of bilirubin, it may be an indication of pancreatic cancer. However, many other medical situations can cause an elevation in bilirubin. Additional testing will almost always be needed to confirm a diagnosis of pancreatic cancer. Liver function tests will also be performed on blood samples to determine if a tumor is affecting the liver.
Imaging is important to detect pancreatic cancer. These tests use a variety of methods to see inside the body. CT scans—or some variation of a CT scan—of the chest, abdomen, and pelvis are most commonly used in the diagnosis of pancreatic cancer.
A CT scan, formerly called computed axial tomography (CAT) scan, uses a large donut-shaped machine to take detailed, cross-sectional, X-ray images from many different angles while the patient lies on a table that moves into the machine. A CT scan may be done at a special center or in a hospital, but it does not require an overnight stay. This test is not painful, and no sedation is needed.
In many centers, modifications of basic CT scanners are used to image the pancreas more accurately.
A helical CT scanner with multiple detector rows, called a multidetector row helical CT (MDCT) scan, is one of the latest technological advances in CT scanners. MDCT has advantages over other CT methods, including improved image resolution and the ability to rapidly scan large volumes, thus allowing for imaging of the entire pancreas in a single breath-hold by the patient.
During an ultrasound, sound waves are bounced off internal organs to produce echoes. The computer creates patterns from these echoes, as normal and abnormal tissues produce different patterns.
EUS and LUS
EUS (endoscopic ultrasound) and LUS (laparoscopic ultrasound) are minimally invasive procedures. EUS is performed using an endoscope, which is a long, thin instrument used to look deep inside the body. During EUS, an endoscope is passed down the esophagus, through the stomach, and into the duodenum. The machine that makes the sound waves is then turned on, and images are created by visualizing the pancreas through the stomach or the duodenum.
Advantages of EUS are that the ultrasound probe can be placed immediately adjacent to the pancreas, producing detailed images. It also allows for biopsies of the pancreas to be obtained to confirm the presence of cancer.
MRI (Magnetic Resonance Imaging) is a non-invasive, painless imaging method that is commonly used today. MRI uses powerful magnets to view internal structures and organs. Since it does not involve radiation, MRI may be safer in patients who require repeated imaging over many years, such as patients with pancreatic cysts.
MRIs are performed at a special imaging center or at a hospital. If you have any metal in your body, such as prosthetic hips, prosthetic knees, pacemakers, and heart valves, you should check with your doctor prior to undergoing an MRI scan.
PET (Positron Emission Tomography) scan is an imaging test that shows not only anatomy, but also biological function. Cancer cells take up sugar at higher rates than normal cells, and during a PET scan, a small amount of radioactive glucose is injected into a vein. A special camera detects the radioactivity that is taken up by malignant tissue. The images created by a PET scan can be used to find cancer cells in the pancreas and in other areas of the body. Recently developed machines combine CT imaging with PET scanning to more accurately identify where cancer is located within the body.
Endoscopic Retrograde Cholangiopancreatography (ERCP)
ERCP is an invasive procedure that is used in conjunction with a dye to view the bile and pancreatic ducts for obstructions. During an ERCP, the patient receives an anesthetic to numb the throat and medication for sedation. A thin tube is passed down the throat, through the stomach, and into the small intestine. Then, X-rays are taken. This is an outpatient procedure but also may be performed in the hospital.
ERCP is especially helpful in patients with jaundice because a stent can be inserted into the bile duct and left in place to keep the bile duct open, often relieving jaundice and its associated symptoms. Tissue samples also can be taken during the procedure. ERCP can cause complications, and is usually used to help manage symptoms and not for diagnostic purposes.
The only definitive way to diagnose cancer is to directly visualize cancer cells under a microscope. After having the necessary blood tests and scans, a biopsy may be performed when pancreatic cancer is suspected. A biopsy is the process of removing tissue samples, which are then examined under a microscope to check for cancer cells.
A biopsy can be performed in an outpatient setting or in the hospital. Biopsy specimens can be obtained in different ways as listed below.
Fine-Needle Aspiration (FNA) Biopsy
In an FNA biopsy, imaging by CT scan or EUS is used together with a long, thin needle to obtain tissue specimens from a tumor. EUS also can be used to place the needle directly through the wall of the duodenum or stomach and into the tumor for collection of tissue specimens.
A brush biopsy procedure is used with ERCP. A small brush is inserted through an endoscope into the bile and pancreatic ducts, and cells are scraped off the insides of the ducts with the brush.
Laparoscopy is a minimally invasive surgical procedure that requires general anesthesia. A laparoscope is inserted through a small incision in the abdomen and the doctor can then view the tumor and remove tissue samples for examination.
Asking good questions will help you get the best care possible for pancreatic cancer.
What type of pancreatic cancer do I have, and what is the stage (resectable, borderline resectable, locally advanced or metastatic)?
Should I have any additional tests to more accurately stage my cancer?
What is the treatment plan that you recommend?
What are the potential benefits, risks, and side effects of that treatment?
Where will the treatment be given, and how often?
How will I know if the treatment is working?
Who will be part of my care team?
Are clinical trials available for my type and stage of pancreatic cancer?
If surgery is recommended, is the center that will perform my surgery a high-volume one?
If I have borderline resectable or locally advanced pancreatic cancer, what will your institution do to try to make my cancer resectable?
Should I have my tumor or my blood (germline) genetically sequenced?
Can you estimate the amount of time I may need to recover from surgery?