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.
Signs and symptoms of small intestine adenocarcinoma
The symptoms of small bowel tumors are often vague. In one study, it took more than 6 months from the time of the first symptom until the diagnosis was made. The most common symptoms are:
- Pain in the abdomen (belly)
- Weight loss
- Weakness and fatigue
Often, the first symptom is pain in the stomach area. This pain may start or get worse after you eat. As the tumor gets larger, it can start to block the passage of digested food. This can lead to increased pain -- it may be more intense and last longer. The tumor can cause a condition called obstruction. When this happens, the intestine is completely blocked and nothing can move through. This leads to pain with severe nausea and vomiting.
Rarely, a cancer will cause a hole in the wall of the intestine, letting the contents of the intestine spill into the abdominal cavity. This is condition is known as perforation. Symptoms of perforation include sudden severe pain, nausea, and vomiting.
Sometimes a tumor will start bleeding into the intestine. If the bleeding is slow, it could lead to anemia (a low red blood cell count). Symptoms of anemia include weakness and fatigue. If the bleeding is rapid, the stool can become black and tarry from digested blood and the patient may feel lightheaded or even pass out.
Medical history and physical exam
When a doctor takes your medical history, you will be asked questions about symptoms and risk factors you may have. 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) measures the cells in the blood, such as the red blood cells, white blood cells, and platelets. Small intestine cancer often causes 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, also known as a barium swallow, is a way to look at the upper part of the digestive tract. For this test, the patient drinks the barium solution and then x-rays are taken. The barium travels through the esophagus and stomach, and then into the first part of the small intestine. If the rest of the small intestine is to be looked at, this test may be 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. For this procedure, 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 travels through the small bowel.
- 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 is 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 are also helpful in staging cancer after it has been diagnosed. They can help tell if your cancer has spread into your lungs, liver, or other organs. They show the lymph nodes and organs where metastatic cancer might be present.
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 are also used to guide a biopsy needle precisely into a suspected metastasis. 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.
This test uses an endoscope − a flexible lighted tube with a video camera on the end. The patient is usually first given medicine to make him or her sleepy. 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). The tissue can be looked at under the microscope to find out if cancer is present and what kind of cancer it is.
Upper endoscopy (also called esophagogastroduodenoscopy or EGD) is used to look at the esophagus, stomach and duodenum (the first part of the small intestine). It is not a good way to look at the rest of the small intestine because the small intestine is so long and has many turns and loops. Newer methods, such as capsule endoscopy and double balloon endoscopy, are more helpful in looking at this area.
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 that is worn around the person's waist while he or she goes 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
Regular 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. First the inner tube, which is an endoscope, goes forward about a foot, 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 keeps being 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 can take a biopsy of anything abnormal. This procedure is done after the patient is given drugs to make him or her sleepy.
A test finds a mass (tumor), but the only way to know if it is cancer 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. This may be done if the tumor cannot be reached with an endoscope.
Last Medical Review: 02/04/2013
Last Revised: 02/04/2013