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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.
You will also have a physical examination. Your doctor will check your abdomen for tenderness, fluid buildup, enlargement of your gallbladderor 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.
• 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?
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
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.
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).
ACT 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 CTimages of body structures. Typically, a contrast agent is also given by mouth to provide better images of the stomach and small intestines. Computed tomography scan of the abdomen showing a pancreatic tumor.
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 scanis 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.
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.
Ultrasonography is another imaging test that is commonly used, and thus, many people arefamiliar with it. Ultrasonography is also calledasonogram, 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.
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.1Ultrasound examination is noninvasive, painless, and can be performed in an outpatient setting. Its major limitation is that gas in the gastrointestinal tract can interferewith 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.
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 viewthe pancreas. This procedure can be done in the hospital or on an outpatient basis.
Magnetic resonance imagingis 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 arecommonly available to avoid the uncomfortable feeling of being in an enclosed space, although images from open MRIs maynot be optimal. The procedure is noninvasive and painless.
MRI uses radio waves and powerful magnets, instead of X-rays as in a CT scan, to viewinternal 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.
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 heartvalves, may cause problems when exposed to high magnetic forces such as those used in MRI.
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.1Recently developed machines combine CT imaging with PET scanning to more accurately identify cancer.
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.
ERCP has advantages over magnetic resonance cholangiopancreatography (see below). ERCP is especially helpful in patients with jaundice because a stentcan 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.9Less invasive tests are being used more often in place of ERCP.
Magnetic resonance cholangiopancreatography (MRCP)is a type of MRI and is an alternativeto ERCP. Itis 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.
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 biopsyis 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. It is generally not necessary to have a biopsy performed prior to surgery.
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.
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.
Laparoscopyis a minimally invasive procedure, during which you will receivegeneral anesthesia. Alaparoscope is inserted through a small incision in the abdomen.The doctor can viewthe tumor and remove tissue samples for examination.
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.
Different tumor markers in the blood areused to detect and monitor many types of cancer. Tumor markersaresubstances, usually complex proteins, produced by tumor cells. Proteinsform 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 havecancer.
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).1These 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.
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, aphysician 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, aphysician 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.
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