How is small intestine adenocarcinoma diagnosed?
If there is a reason to suspect you have a small intestinal cancer, the doctor will use one or more methods to find out if the disease is really present.
Medical history and physical exam
When a doctor takes your medical history, you will be asked questions about your symptoms and risk factors. The doctor will specifically ask about symptoms that could be caused by a mass in the intestines and examine you, concentrating on your abdomen looking for any swelling or sounds of the bowel trying to overcome a blockage.
If your doctor suspects an intestine cancer, he or she will likely order some blood tests, such as:
- A complete blood count (CBC), which measures red blood cells, white blood cells, and platelets. Small intestine cancer often causes a low red blood cell count (anemia)
- Blood chemistry tests to look for signs that a cancer has spread to the liver
For these studies, a liquid containing barium (also called a contrast liquid) is swallowed to coat the lining of an area in the intestines or stomach, and then x-rays are taken. The barium helps outline abnormalities in the esophagus, stomach, and intestines, making them more visible. These x-rays are most often used to look at the upper or lower parts of the digestive system, and can help find tumors there. They are least helpful in finding small intestine tumors. Barium studies were used more often before endoscopy was available.
- Upper GI series: This test is a way to look at the upper part of the digestive tract. The patient drinks a white, chalky solution containing barium and then x-rays are taken. The barium coats the surface of the esophagus, stomach, and first part of the small intestine so that abnormalities show up on x-ray. To look for problems in the rest of the small intestine, more x-rays can be taken over the next few hours as the barium passes through the intestines. This is called a small bowel follow-through. This test often gives good pictures of the first part of the small intestine (the duodenum), but the rest of the small intestine may be hard to see in detail.
- Enteroclysis: This procedure gives more detailed pictures of the small intestine than the upper GI with small bowel follow-through. A tube is passed from the nose or mouth through the stomach and into the small intestine. Then, barium is sent through the tube directly into the small intestine. X-rays are taken as the contrast moves through the small intestine.
- Barium enema: This is a way to look at the large intestine. Before this test, the bowel needs to be cleaned out. This is done by using strong laxatives and enemas the night before and the morning of the exam. For this test, the barium solution is given into the large intestine through the anus (like an enema). For better pictures, air can be injected into the intestine through a tube. This is called air contrast. This procedure is meant to be used to look at the large intestine, but sometimes the last part of the small intestine can be seen as well.
A computed tomography (CT or CAT) scan is an x-ray procedure that makes detailed cross-sectional images of your body. Instead of taking one picture, like a conventional x-ray, a CT scanner takes many pictures as it rotates around you. A computer then combines these pictures into an image of a slice of your body. The machine takes pictures of multiple slices of the part of your body that is being studied.
A CT scanner has been described as a large donut, with a narrow table in the middle opening. You will need to lie still on the table while the scan is being done. CT scans take longer than regular x-rays, and you might feel a bit confined by the ring while the pictures are being taken.
CT scans are often used in people with abdominal pain to try to find the source of the problem. Although small intestine tumors may not be seen well by CT, these scans are good at showing some of the problems that these tumors can cause (like obstruction or perforation). CT scans can also help find areas of cancer spread.
Before the test, you may be asked to drink 1 or 2 pints of a contrast liquid. This helps outline the intestine so that certain areas will not be mistaken for tumors. You may also get an IV (intravenous) line through which a different kind of contrast dye is injected. This helps better outline structures in your body.
The injection can cause some flushing (redness and warm feeling that may last hours to days). A few people are allergic to the dye and get hives. Rarely, more serious reactions like trouble breathing and low blood pressure can occur. Medicine can be given to prevent and treat allergic reactions. Be sure to tell the doctor if you are allergic to shellfish or have ever reacted to any contrast material used for x-rays.
CT scans can also be used to guide a biopsy needle precisely into an abnormal area that could be cancer spread. For this procedure, called a CT-guided needle biopsy, the patient remains on the CT scanning table, while a radiologist moves a biopsy needle toward the location of the mass/tumor. CT scans are repeated until the doctors are confident that the needle is within the mass. A fine-needle biopsy sample (tiny fragment of tissue) or a core-needle biopsy sample (a thin cylinder of tissue about ½-inch long and less than 1/8-inch in diameter) is removed and looked at under a microscope.
Upper endoscopy (also called esophagogastroduodenoscopy or EGD) is used to look at the esophagus, stomach and duodenum (the first part of the small intestine). This test uses an endoscope − a flexible lighted tube with a video camera on the end. The endoscope goes in through the mouth, and then passes through the throat and the esophagus into the stomach and then into the first part of the small intestine. This allows the doctor to see clearly any masses in the lining of the digestive organs. If abnormalities are found, small pieces of tissue can be removed through the endoscope (biopsy) and looked at under a microscope to see if cancer is present.
Most patients having this test are given medicine to make them sleepy. If this is the case, they will need someone to take them home (not just a cab).
This test is helpful in looking at the first part of the small intestine. Other tests, such as capsule endoscopy and double-balloon enteroscopy, are needed to look at the rest of the small intestine.
This procedure does not actually use an endoscope. Instead, the patient swallows a capsule (about the size of a large vitamin pill) that has a light and a very small camera. Like any other pill, the capsule goes through the stomach and into the small intestine. As it travels through the small intestine (usually over a period of about 8 hours), it takes thousands of pictures. The camera sends the images to a device the person wears around the waist while going on with normal daily activities. The pictures can then be downloaded onto a computer, where the doctor can look at them as a video. The capsule passes out of the body during a normal bowel movement and is flushed away.
Double-balloon enteroscopy (endoscopy)
Regular upper endoscopy cannot look very far into the small intestine because it is too long (20 feet) and has too many curves. This method gets around these problems by using a special endoscope that is made up of 2 tubes, one inside the other. The procedure can start like a regular upper endoscopy, with the endoscope going in through the mouth, down the throat and esophagus, and through the stomach into the small intestine. Then the inner tube, which is an endoscope, goes forward a small distance, and then a balloon at its end is inflated to anchor it. Then the outer tube goes forward to near the end of the inner tube and it is then anchored in place with a balloon. This process is repeated over and over, letting the doctor see the intestine a foot at a time. An advantage of this over capsule endoscopy is that the doctor will be able to biopsy anything abnormal.
Another way of doing this is to go through the colon to get to the small intestine, so that it starts out like a regular colonoscopy. If that is done, the patient has to clean out the colon the night before the procedure. This is most often done by drinking a large amount (2 to 4 quarts) of a liquid laxative solution, which results in spending much of the evening in the bathroom.
Using either approach, this procedure is done after the patient is given drugs to make him or her sleepy (sedation) or even asleep (general anesthesia), so he or she will need someone to take them home (not just a cab).
Procedures such as endoscopy and imaging tests can find areas that look like cancer, but the only way to know for certain is to do a biopsy. In a biopsy, a piece of the abnormal area is removed and examined under a microscope.
There are several ways to take a sample of an intestinal tumor. One way is through the endoscope. When a tumor is found, the doctor can use biopsy forceps (pincers or tongs) through the tube to take a small sample of the tumor. The specimen the doctor takes will be very small, but doctors can usually make an accurate diagnosis. Bleeding after a biopsy is a rare but potentially serious problem. If bleeding becomes a problem, doctors can sometimes inject drugs that constrict blood vessels through the endoscope into the tumor to stop the bleeding.
In some patients, surgery is needed to biopsy a tumor in the intestines. This may be done if the tumor cannot be reached with an endoscope.
Sometimes CT scans or other imaging tests are used to guide a needle to biopsy tumors in other organs (like the liver) to see if they are cancer.
Last Medical Review: 04/30/2014
Last Revised: 05/08/2014