Small Intestinal Cancer

Small intestinal cancer occurs in the gastrointestinal (GI) tract or digestive tract. This cancer is less common than most other types of GI cancers. In fact, they account for fewer than 1 in 10 cancers of the GI tract, and fewer than 1 in 100 cancers overall.

Types & Stages

The small intestine is made up of many different types of cells, so different types of cancer can start here. The four major types of small intestinal cancers are:

• Adenocarcinomas. This type starts in the gland cells that line the inside of the intestine. They account for about 1 in 3 small intestinal cancers.
   
• Carcinoid tumors. A type of neuroendocrine tumor that tends to be slow growing and is the most common type of small intestinal tumor.
   
• Lymphomas. This type starts in immune cells called lymphocytes. Lymphomas can start almost anywhere in the body, including the small intestine.
   
• Sarcomas. This type starts in connective tissues, such as muscle. The most common sarcomas in the intestine are known as gastrointestinal stromal tumors (GISTs), which start from nerve cells in the wall of the gastrointestinal tract. Some are benign (not cancer). These tumors are most commonly found in the stomach and small intestine. 

Signs & Symptoms

The symptoms of small intestinal cancers are often vague and can have other, more common causes. Unfortunately, this means that it’s often at least several months from the time symptoms start until the cancer is diagnosed. Some of the more common symptoms of small intestinal cancer are:

• often the first symptom is pain in the stomach area; crampy and may not be constant
• nausea and vomiting
• unexplained weight loss
• weakness and feeling tired
• dark-colored stools (from bleeding into the intestine)
• low red blood cell counts (anemia)
• yellowing of the skin and eyes (jaundice)

Anyone experiencing these symptoms should speak with their primary care physician. If the tumor gets large enough, it can cause an obstruction, in which the intestine is completely blocked and nothing can move through. This leads to pain with severe nausea and vomiting.

Diagnosis

Small intestinal cancers are often found because of signs or symptoms a person is having (see above). But these symptoms aren’t usually enough to know for sure if you have a small intestinal cancer or some other type of health problem. If a tumor is suspected, your doctor will examine you, focusing on your abdomen looking for any swelling or sounds of the bowel trying to overcome a blockage.  

If your doctor suspects a small intestinal cancer, they will likely order some blood tests, such as a complete blood count (CBC), which measures the levels of red blood cells, white blood cells and platelets. Small intestinal cancer often causes bleeding into the intestines, which can lead to a low red blood cell count (anemia). So the doctor will also order blood chemistry tests to look for signs that a cancer might have spread to the liver or other problems.

They might also order imaging tests, which include:

• Upper GI series: For this test, you’ll be given a barium liquid to drink, and then X-rays are done to look at the upper part of the digestive tract (the esophagus, stomach and first part of the small intestine). 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 test gives more detailed pictures of the small intestine than the upper GI series with small bowel follow-through. A thin tube is passed down your 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 liquid moves through the small intestine.
   
• Barium enema (lower GI series): This is a way to look at the large intestine (colon and rectum). Before this test, the bowel needs to be cleaned out, so you’ll be given strong laxatives and enemas the night before and the morning of the exam. For this test, the barium solution is given into your large intestine through a flexible tube that is put into your anus (like an enema). For better pictures, air can also 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.

You might have computed tomography (CT) scans, which uses X-rays to make detailed cross-sectional images of your body. Unlike a regular X-ray, a CT scan creates detailed images of the soft tissues in the body. You might also need: 

• CT enteroclysis, which is sometimes used to get a better view of the intestine than a standard CT can provide. Before the scan, a thin tube is passed down your nose or mouth and down to the small intestine. A large volume of a liquid contrast agent is then put into the tube, which helps expand the intestine and makes it easier to see on a CT scan.   
   
• CT-guided needle biopsy uses a biopsy needle precisely into an abnormal area that could be cancer spread. For this procedure, you’ll stay on the CT scanning table while your doctor moves a biopsy needle through the skin and toward the location of the mass/tumor. CT scans are repeated until the needle is within the mass. Small samples of tissue are then removed and looked at under a microscope.

Your doctor might also do magnetic resonance imaging (MRI) to show detailed images of soft tissues in the body. This might include: 

• MR enteroclysis to get a better view of the intestine than a standard MRI can provide. Before the scan, a thin tube is passed down your nose or mouth and down to the small intestine. A large volume of a liquid contrast agent is then put into the tube, which helps expand the intestine and makes it easier to see on an MRI.     
   
• Endoscopy in which your doctor puts a flexible, lighted tube (endoscope) with a tiny video camera on the end into your body to see the inner lining of the GI tract. If abnormal areas are found, small pieces can be biopsied (removed) through the endoscope.
   
• Upper endoscopy, also called esophagogastroduodenoscopy or EGD, is used to look at the esophagus, stomach and duodenum (the first part of the small intestine). The endoscope is put in through your mouth, and then passes through your esophagus, into the stomach, and then into the first part of the small intestine. If your doctor sees any abnormal areas, small pieces of tissue can be removed to be looked at under a microscope to see if cancer is present.

All these tests are 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.

• Capsule endoscopy involves swallowing a capsule (about the size of a large vitamin pill) that has a light and a very small camera. The capsule goes through the stomach and into the small intestine. As it travels through the small intestine (usually over about eight hours), it takes thousands of pictures. The camera sends the images to a device that you wear around your waist while going about normal daily activities. The pictures can then be downloaded onto a computer, where your doctor can look at them as a video. The capsule passes out of your body during a normal bowel movement and is flushed away.

• Double-balloon enteroscopy (endoscopy) is useful because most of the small intestine can't be viewed with an upper endoscopy because it’s too long (about 20 feet) and has too many curves. Double-balloon enteroscopy gets around these problems by using a special endoscope that is made up of two tubes, one inside the other. 

  You’re given intravenous (IV) medicine to help you relax, or even general anesthesia (so that you are asleep). The endoscope is then inserted either through your mouth or anus, depending on if there is a specific part of the small intestine to be looked at. Once in the small intestine, the inner tube, which is an endoscope, is pushed forward a small distance, and then a balloon at its end is inflated to anchor it. Then the outer tube is pushed forward to near the end of the inner tube and 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. This test can sometimes be helpful when done with capsule endoscopy. An advantage of this test over capsule endoscopy is that the doctor can biopsy anything that looks abnormal.

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 looked at under a microscope. There are different ways to take biopsy samples of an intestinal tumor.

• A biopsy can be done during an endoscopy. When a tumor is found, your doctor can use biopsy forceps (pincers or tongs) through the tube to take small samples of the tumor. The samples are very small, but they can usually make an accurate diagnosis.
   
• For 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 thin, hollow needle to biopsy tumors in other organs (like the liver) to see if they are cancer.

Treatment    

Surgery is typically the main treatment for small intestinal cancer, though patients may also receive chemotherapy and radiation. The type of operation will depend on a number of factors, including the size and location of the tumor, and whether you have any serious health problems. Options include:

• Segmental resection: This operation removes (resects) the segment of intestine that has the tumor, as well as some of the normal tissue on either side of the tumor. The two cut ends of intestine are then attached back together. Some nearby tissue containing lymph nodes is also removed. Tumors in the end of the ileum (the last part of the small intestine) may require removing the right side of the colon (the first part of the large intestine). This surgery is called a hemicolectomy.

  Usually this surgery is done through a long cut made in the abdomen. Another option for some smaller cancers might be “keyhole” (laparoscopic) surgery, in which the operation is done through several small cuts using long, thin surgical tools. After surgery, it can take a few days before you can eat and drink normally. Removing a small piece of intestine usually doesn’t cause long-term problems with eating or bowel movements, but there are more likely to be issues if part of the colon is removed as well.

• Pancreaticoduodenectomy (Whipple procedure): This extensive operation can be used to treat cancers of the duodenum (the first part of the small intestine). It removes the duodenum, part of the pancreas, part of the stomach and nearby lymph nodes. The gallbladder and part of the common bile duct are also removed, and the remaining bile duct is then attached to the small intestine so that bile from the liver can continue to enter the small intestine. Stony Brook Cancer Center is a leader in this procedure for pancreatic cancer.

If the cancer can't be removed completely because it has spread too far, surgery might still be a good option to help prevent or relieve some symptoms from the cancer. This is known as palliative surgery. Often, these operations are done to relieve a blocked intestine, to decrease pain, nausea and vomiting, and allow you to eat normally. If possible, your surgeon will remove enough of the tumor and nearby intestine to allow digested food to pass through.

• Bypass surgery: Another option might be for your surgeon to leave the tumor in place and to reroute normal parts of the small intestine around the tumor to prevent or relieve a blockage.
   
• Stent or tube placement: If major surgery isn’t a good option, sometimes an endoscope can be used to pass a fairly rigid tube (called a stent) down the digestive tract and into the blocked part of the intestine. The stent is left in place to help keep the intestine open and allow digested food to pass.

If this can’t be done, a thin, flexible tube may be placed through the skin and into the stomach to drain it. The tube can be left in place to help prevent problems with nausea and vomiting.

Causes & Risk Factors

Factors that may increase the risk of small intestinal cancers include:

• Gender. They occur slightly more often in men than in women.
   
• Age. Cancers of the small intestine tend to occur more often in older people. They’re most often found in people in their 60s and 70s.
   
• Race/ethnicity. In the United States, Black people are affected more often by these cancers than people of other races/ethnicities.
   
• Smoking and alcohol use. Some studies have found an increased risk with either smoking or drinking alcohol, but not all studies have found this.
   
• Diet. Some research suggests that diets high in red meat and salted or smoked foods might raise the risk of small intestinal cancer.
   
• Celiac disease. For people with celiac disease, eating gluten (a protein that is found in wheat and some other types of grain) causes the body's immune system to attack the lining of the intestines. People with celiac disease have an increased risk of a certain kind of lymphoma of the intestine called enteropathy-associated T-cell lymphoma. They may also have an increased risk of small intestinal cancer.
   
• Colon cancer. People who have had colon cancer have an increased risk of getting cancer of the small intestine. This could be due to shared risk factors.
   
• Crohn's disease is a condition in which the immune system attacks the gastrointestinal (GI) tract. This disease can affect any part of the GI tract, but it most often affects the lower part of the small intestine. People with this condition have a much higher risk of small intestinal cancer (particularly adenocarcinoma). These cancers are most often seen in the ileum (the last part of the small intestine, near the colon).
   
• Inherited syndromes. People with certain inherited conditions have a higher risk of small intestinal cancer (mainly adenocarcinoma). These include familial adenomatous polyposis (FAP), Lynch syndrome (hereditary nonpolyposis colorectal cancer or HNPCC), Peutz-Jeghers syndrome (PJS), and MUTYH-associated polyposis.
   
• Cystic fibrosis (CF). Often, in someone with CF, the pancreas cannot make the enzymes that break food down so that it can be absorbed. People with CF have an increased risk of small intestinal cancer. A child must have two abnormal copies of the CFTR gene (one from each parent) to get this disease.

Screening

Because small intestine adenocarcinomas are rare, and no effective screening tests have been found for these cancers, routine testing for people without any symptoms isn’t recommended.  But for people who are increased risk for small intestinal cancers—because you have inherited genetic syndromes (see above)—your doctor might recommend regular tests to look for cancer early, especially in the duodenum (the first part of the small intestine). Tests that might be done include upper endoscopy (in which a long tube with a tiny video camera on the end is passed down the throat, through the stomach, and into the duodenum), CT scans and endoscopic ultrasound.