Small Bowel Tumours and Cancer

The small bowel, also known as the small intestine, is a portion of the digestive tract. The small bowel extends between the stomach and the large bowel (colon). It has three distinct regions – the duodenum, jejunum, and ileum.

Types of Cancer

There are four main types of small bowel cancer. They are named after the cells where they develop:

Adenocarcinoma starts in glandular cells in the lining of the small intestine and is the most common type of small intestine cancer. Usually, this type of tumours occur in the part of the small intestine near the stomach. If left untreated, they may grow and block the intestine.

Sarcoma of the intestine originates in the submucosa and grows longitudinally, attacking the intestinal wall to such an extent that it is transformed into a rigid, inflexible tube. It is an extremely rare disease, with very few cases reported and little information available to patients.

Neuroendocrine (carcinoid) cancers or tumours of the small bowel tend to occur in the ileum. Carcinoid tumours are among the most common small bowel cancers.

Lymphoma of the small intestine starts in the lymph tissue of the small bowel and usually occurs in the jejunum.

Occasionally, small bowel cancer may actually be metastatic cancer, meaning that it has spread to the small bowel from a primary cancer located elsewhere in the body.

Symptoms of small bowel cancer

When tumours develop, they may ulcerate, leading to pain and bleeding. Sometimes these common symptoms of small bowel cancer include:

  • Nausea and vomiting
  • Mass in the abdomen
  • Cramping pain
  • Acid reflux
  • Unexplained or unintentional weight loss
  • Blood in the stool
  • Constipation
  • Dark or black stools (bowel motions), due to bleeding in the small bowel
  • Diarrhoea
  • Anaemia (a low number of red blood cells), due to blood loss

Tumours may develop in the periampullary and ampullary portions of the duodenum. This is the area where bile enters the small intestine. Tumours in this location often present with jaundice.

Causes and Risk Factors

In some cases, intestinal cancer may occur due to genetic abnormalities. However, certain lifestyle and nutrition choices appear to increase the risk for duodenal and small bowel cancer significantly.

These include:

  • A diet rich in fat but low in nutrients
  • Exposure to carcinogens, especially in the form of viruses, radiation and chemicals
  • Smoking
  • A history of gastrointestinal conditions


Intestinal cancer does not present any symptoms until the tumour is big enough to bleed or cause a blockage. This makes it difficult for doctors to diagnose the condition at an early stage, when treatment is likely to be most effective.

It is always important to get any intestinal anomalies checked, to provide for early detection of any existent small bowel cancer. Tests may include endoscopies, x-rays, CT or MRI scans. Doctors may also need to collect tissue samples (biopsy) from the affected area for laboratory analysis.


Surgery is the main treatment for cancer of the small bowel. The affected section of the bowel is removed and the healthy bowel is joined back together. Radiotherapy or chemotherapy may be used before and /or after surgery, or used in combination (chemo radiation).