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How is Pancreatic Cancer Diagnosed?
INITIAL EXAMINATION | Imaging Tests | Biopsy | Blood Tests | Results
Several steps are involved in making a diagnosis of pancreatic cancer. The first thing your doctor will do is ask questions
about your medical history, family history, possible risk factors, and symptoms ( Box 4-1 ). Answering these questions honestly and completely will help both you and your doctor during the diagnostic process.
| Box 4-1 |
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MEDICAL HISTORY QUESTIONS 1
• Where do you have the pain?
• How long have you had the pain?
• How bad is the pain, for example, on a scale from 1 to 10?
• Are you able to do anything to make the pain happen?
• Are you able to do anything to make the pain go away?
• Have you lost weight without trying?
• What other symptoms do you have?
• If you have jaundice: When did you notice the jaundice?
• If you have dark urine or light stools: How long have you had this?
• Has anyone in your family ever had cancer?
• Has anyone in your family ever had pancreatic cancer?
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You will also have a physical examination. Your doctor will check your abdomen for tenderness, fluid buildup, enlargement
of your gallbladder or liver (that may result from blockage of the bile duct), and masses. Your lymph nodes will be checked for tenderness and
swelling. Any sign of jaundice will be noted. Your doctor also may order blood or urine tests, testing of stool samples, or
imaging tests.
IMAGING TESTS
The most important tests used to detect pancreatic cancer are imaging tests. These tests use a variety of methods to see inside the body. Imaging tests can be simple X-rays or more complex scanning
methods that use computers to reconstruct the structures in the body. Some typical imaging tests are described in this section,
and their uses are listed in Table 4-1 .
Keep in mind that results from many of the imaging tests outlined in this section are complementary to each other. Your doctor
will decide which tests would be best, given your particular situation.
| Imaging Test |
Use(s) |
Computed tomography
(CT) scan
|
- Can help determine if the tumor is localized or has spread |
| CT scan with contrast dye |
- Can detect abnormal masses
- Can detect blockages of the pancreatic and bile ducts
|
Dual-phase helical CT scan
|
- Can detect 98% of pancreatic cancers
- Can detect distant metastases
|
| Multidetector row CT (MDCT) scan |
- Has improved image resolution
- Can rapidly scan large volumes
|
| Ultrasonography |
- Can determine if pancreatic tissue is normal or abnormal
- Can help detect blockages of the pancreatic and bile ducts
|
| Endoscopic ultrasonography (EUS) |
- Highly reliable
- Can determine local extent of disease
- Can detect lesions in the head, body, and tail of the pancreas
- Tissue samples can be taken at the same time
|
| Laparoscopic ultrasonography (LUS) |
- Can determine if the tumor has spread to the peritoneum
- Can detect liver metastases
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| Magnetic resonance imaging (MRI) |
- Can detect masses
- Can detect blockages
|
| Positron emission tomography (PET) scan |
- Can show the difference between healthy and abnormal tissue in the entire body |
Endoscopic retrograde
cholangiopancreatography(ERCP)
|
- Can detect obstructions in the pancreatic and bile ducts
- Usually reserved for people who require stent placement for symptom management
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Magnetic resonance
cholangiopancreatography(MRCP)
|
- Can detect obstructions in the pancreatic and bile ducts |
Computed Tomography (CT) Scan
Many people either are familiar with or have had a computed tomography (CT) scan, which is also called a CAT scan. The CT machine is very large and shaped like a donut. During a CT scan, you will lie on
a table that will move into the machine. The scanner will take detailed, cross-sectional, X-ray images from many different
angles. The computer combines these images into a series of views of the area in question for diagnostic purposes. ( Figure 4-1 ). 1
A CT scan may be done at a special center or in a hospital but does not require an overnight stay. This test is not painful,
and no sedation is needed.
A dye, called a contrast agent, can be injected into a vein to produce better CT images of body structures. Typically, a contrast agent is also given by
mouth to provide better images of the stomach and small intestines.
In many centers, modifications of basic CT scanners are used to image the pancreas more accurately. Two of these modified
scanners are a dual-phase helical CT scan and a multi-detector row helical CT scan. A dual-phase helical (also called spiral) CT scan is a sensitive imaging test used to evaluate patients suspected of having pancreatic cancer. Dual-phase helical CT scanning
produces detailed, three-dimensional images of the pancreas. It is estimated that this type of CT scan can diagnose about
98% of all pancreatic cancers and distant metastases. 6
| A Dual-phase helical CT scan is often called a 3D CT scan.
This imaging technique uses a X-ray beam that remains on while rotating around the patient. The scan is timed so that the
pancreas and liver are scanned at the optimal time for the contrast dye to be effective. The resulting image is a highly accurate
three-dimensional image obtained in a shorter time than a conventional 2-D CT scan.
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A helical CT scanner with multiple detector rows, called a multi-detector 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. 7
Ultrasonography
Ultrasonography is another imaging test that is commonly used, and thus, many people are familiar with it. Ultrasonography is also called
a sonogram, an ultrasonogram, or an ultrasound scan. During this test, sound waves are bounced off internal organs to produce
echoes. The computer creates patterns from these echoes. Because echoes from normal and abnormal tissue produce different
patterns, pancreatic cancer can be detected. 1
During a sonogram, an ultrasound probe will be placed on your abdomen and moved methodically. Images of the echo patterns
will be displayed on a computer screen. 1 Ultrasound examination is noninvasive, painless, and can be performed in an outpatient setting. Its major limitation is that
gas in the gastrointestinal tract can interfere with the sound waves, and therefore, it is not considered a very sensitive
test to detect pancreatic cancer.
There are two other types of sonograms, endoscopic ultrasonography (EUS) and laparoscopic ultrasonography (LUS). Each is a minimally invasive procedure. EUS is performed using an endoscope, which is a long, thin instrument with a light at the end used to look deep inside the body. During EUS, you will receive
numbing medication for your throat and medication for sedation. The 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. 1,8
Advantages of EUS are that the ultrasound probe can be placed immediately adjacent to the pancreas, producing detailed images,
and tissue samples can be obtained through the same instrument.
The LUS procedure is not used as often as EUS but may be employed to evaluate whether the cancer has spread to the peritoneum, which is the membrane that lines the abdominal cavity and covers most of the abdominal organs. During an LUS procedure,
typically, general anesthesia is given. A small incision will be made in the abdomen, and the doctor will use a laparoscope (a small telescope-like instrument connected to a video monitor) to view the pancreas. This procedure can be done in the
hospital or on an outpatient basis. 8
Magnetic Resonance Imaging (MRI)
Magnetic resonance imaging is another imaging method that is in common use today, and many people are familiar with it. When having an MRI, you lie
on a table that is moved into a narrow tube. Today, open MRIs are commonly available to avoid the uncomfortable feeling of
being in an enclosed space, although images from open MRIs may not be optimal. The procedure is noninvasive and painless.
1
MRI uses radio waves and powerful magnets, instead of X-rays as in a CT scan, to view internal structures and organs. The
energy from the radio waves is absorbed by the body and then released. A computer translates the patterns formed by this energy
release into detailed images of areas inside the body. MRI produces cross-sectional slices like a CT scanner, but also produces
slices that are parallel to the length of the body. 1
An MRI scan is performed at a special imaging center or at a hospital. If you have any metal in your body, you should check
with your doctor prior to undergoing an MRI scan. Some types of metal implants, such as prosthetic hips, knees, pacemakers,
and heart valves, may cause problems when exposed to high magnetic forces such as those used in MRI.
Positron Emission Tomography (PET Scan)
Positron emission tomography, or PET scan, is an imaging test that shows not only anatomy but also biological function. During a PET scan, a small amount of radioactive glucose (sugar) is injected into a vein. Then a special camera detects the radioactivity that is preferentially taken up by malignant
tissue, and a computer creates detailed images. Because cancer cells often absorb much more glucose than normal cells do,
the images created by a PET scan can be used to find cancer cells in the pancreas and in other areas of the body.1 Recently
developed machines combine CT imaging with PET scanning to more accurately identify cancer.
Endoscopic Retrograde Cholangiopancreatography (ERCP)
Endoscopic retrograde cholangiopancreatography, or 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, you will receive 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. From there, the gastroenterologist who is performing the procedure
will identify the pancreatic duct so that the dye can be injected into it. Then X-rays are taken. This is an outpatient procedure
but also may be performed in the hospital. 9
ERCP has advantages over magnetic resonance cholangiopancreatography (see below). ERCP is especially helpful in patients with
jaundice because a stent can be inserted and left in place to keep ducts open, often relieving the jaundice and its associated
symptoms. Tissue samples also can be taken during the procedure. 9 Less invasive tests are being used more often in place of ERCP. 10
Magnetic Resonance Cholangiopancreatography (MRCP)
Magnetic resonance cholangiopancreatography (MRCP) is a type of MRI and is an alternative to ERCP. It is safer and faster than ERCP, because it is noninvasive and no dye is
used. MRCP is used to view the pancreatic and bile ducts, which are difficult to see with CT or MRI. No sedation or preparation
on the part of the patient is needed, except for fasting. 3,4 Typically, MRCP is combined with MRI.
BIOPSY
Because the only definitive way to diagnose cancer is to directly visualize cancer cells under a microscope, 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. 9 A biopsy can be performed in an outpatient setting or in the hospital.
Biopsy specimens can be obtained in different ways. It is generally not necessary to have a biopsy performed prior to surgery.
Fine-Needle Aspiration (FNA) Biopsy
In a fine-needle aspiration (FNA) biopsy, imaging by CT or EUS is used together with a long, thin needle to obtain tissue specimens. The CT or EUS imaging method allows
the doctor to view the position of the needle to ensure that the needle is in the 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. General
anesthesia is not required, but local anesthesia may be provided. 1
Brush Biopsy
A brush biopsy procedure is used with ERCP. A small brush is inserted through an endoscope into the bile and pancreatic ducts. Cells are
scraped off the insides of the ducts with the brush. 1
Laparoscopy
Laparoscopy is a minimally invasive procedure, during which you will receive general anesthesia. A laparoscope is inserted through a
small incision in the abdomen. The doctor can view the tumor and remove tissue samples for examination. 1
BLOOD TESTS
Blood tests are frequently performed for diagnostic purposes. No single blood test can be used to make a diagnosis of pancreatic
cancer. When a person has pancreatic cancer, however, elevated levels of bilirubin or liver enzymes may be present. 6
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. Proteins form the basis of body structures such as cells, tissues, and organs. Enzymes and some hormones are composed of protein.
Some tumor markers can indicate specific types of cancer; others are found in several types of cancer. Many of the well-known
tumor markers, such as PSA for screening prostate cancer, are also found in people who do not have cancer. 11
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). 1 These markers are not accurate enough to be used to screen healthy people for 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 protein 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. 11
TEST RESULTS
If you have blood and urine testing, your doctor will receive written reports from the laboratory. If the 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 establish a diagnosis of pancreatic cancer. Liver function
tests will also be performed on blood samples to determine if a tumor is affecting the liver.
Results of imaging tests such as CT and MRI scans will be conveyed to your doctor by a radiologist, a physician who is trained to interpret many different types of imaging techniques. The radiologist will consult with your
doctor and provide a written report of the results.
If you have a biopsy procedure performed, your doctor will receive a written report from the pathologist, a physician trained to examine cells under a microscope in the laboratory for cancer and other diseases. Your doctor may
also speak with the pathologist to obtain a better understanding of your disease. The results of the biopsy will help your
doctor make treatment recommendations, and can help you make treatment decisions.
REFERENCES ! Click reference number to return to text.
1. American Cancer Society. Pancreatic cancer. http://documents.cancer.org/ 116.00. Accessed April 14, 2007.
2. JAMA Patient Page. Pancreatic cancer. www.jama.com. Accessed April 1, 2007.
3. Kaltenthaler E, Vergel YB, Chilcott J, et al. A systematic review and economic evaluation of magnetic resonance cholangiopancreatography
compared with diagnostic endoscopic retrograde cholangiopancreatography. Health Technology Assessment. 2004;8(10). www.ncchta.org/execsumm/summ810.htm.
Accessed April 13, 2007.
4. Miller JC. Magnetic resonance cholangiopancreatography (MRCP). www.massgeneralimaging.org/newsletter/june_2004. Accessed
April 13, 2007.
5. University of Pittsburgh Medical Center Health System. Percutaneous transhepatic cholangiography and biliary drainage. http://patienteducation.upmc.com/Pdf/CholangBiliDrain.pdf.
Accessed April 13, 2007.
6. Freelove R, Walling AD. Pancreatic cancer: diagnosis and management. Am Fam Phys. 2006;73:485-92.
7. Fishman EK, Horton KM. The increasing impact of multidetector row computed tomography in clinical practice. Eur J Radiol.
2007;62:(Suppl)1-13.
8. Yang GY, Wagner TD, Fuss M, Thomas CR. Multimodality approaches for pancreatic cancer. CA Cancer J Clin. 2005;55:352-67.
9. National Cancer Institute. Pancreatic cancer (PDQ®) treatment. Patient Version. April 14, 2005. www.cancer.gov/cancertopics/pdq/treatment/pancreatic/
patient/allpages. Accessed April 12, 2007.
10. Stevens T, Conwell DL. Pancreatic neoplasms. www.clevelandclinicmeded.com/diseasemanagement/gastro/pneo/pneo.htm. Accessed
April 6, 2007.
11. Lab Tests Online. http://labtestsonline.org. Accessed April 20, 2007.
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