A rare condition in which cancerous tumors develop in the small bowel. The most common types include adenocarcinoma, lymphoma, sarcoma, and carcinoids. All of these tumors have the potential to invade the bowel wall, spread into adjoining lymph nodes, and metastasize.
In developed nations, adenocarcinomas are most common whereas in developing countries, lymphomas are much more common. At the start of the 21st century, doctors in the US were diagnosing only about 1,200 malignant small intestine tumors each year – a very small number compared to the frequency of tumors in other parts of the GI tract.
Put another way, cancer is 50 times more common in your large bowel than in your small bowel. This may be due to several factors, such as the liquid nature of the contents of the small intestine (less irritation), the rapid transit time (less exposure time to toxic agents), the low bacteria count, or the alkaline pH.
Risk factors include the following:
Symptoms of advanced disease include fatigue, weight loss, iron deficiency anemia, visible blood loss (vomiting blood or a material that looks like coffee grounds, or black stools), severe nausea and vomiting (because of the blockage caused by the cancer in the small bowel), jaundice (when the cancer involves the upper small intestine and blocks the bile ducts draining the liver).
Doctors frequently diagnose small intestine cancer during surgery for unexplained bowel obstruction. If cancer is suspected, doctors usually choose to perform a barium contrast study of the small intestine. Upper GI tract endoscopy may be useful in detecting areas of concern in the immediate upper GI tract, and a CT scan of the abdomen or an abdominal ultrasound may help to visualize bulky tumors and to rule out any spread of the cancer to adjacent lymph nodes and distant organs such as the liver. A colonoscopy may help diagnose tumors involving the lower areas of the small bowel.
Surgical removal is the primary treatment for cancer of the small intestine. Chemotherapy or radiation therapy may be useful if the cancer is widespread; radiation therapy also may be helpful if there is widespread disease or if local tumors come back. Surgery may relieve symptoms when the cancer has caused a bowel obstruction. In this case, doctors may perform a bypass procedure or limited tumor removal.
Fewer than 35% of people who have adenocarcinoma of the small bowel have a live more than 5 years after diagnosis. Survival chances are better if the cancer is limited to the inner walls of the small intestine and the lymph nodes are not involved. Chances are better still if the patient has a carcinoid tumor or lymphoma of the small bowel – these malignancies tend to respond better to chemotherapy and radiation treatment when doctors cannot completely remove the tumor. The prognosis is poor, however, if there is a small bowel lymphoma alongside celiac disease or a weakened immune system.
Adenocarcinoma of the small bowel is associated with Crohn's disease, which usually occurs in the lower part of the small intestine (the ileum). The inflammation extends deep into the lining of the affected organ, causing pain and making the intestines empty frequently, resulting in diarrhea. For those with Crohn's disease, the risk of developing small intestinal cancer is 6 times greater than for those without it. Additional risk factors for those with Crohn's disease include:
Your body is a highly complex, interconnected system. Instead of guessing at what might be wrong, let us help you discover what is really going on inside your body based on the many clues it is giving.
Our multiple symptom checker provides in-depth health analysis by The Analyst™ with full explanations, recommendations and (optionally) doctors available for case reviews and answering your specific questions.