The types of small bowel cancer may include:¹

• Adenocarcinoma - Starts in the epithelial cells (cells that release mucus) lining the inside of the small bowel
• Sarcoma - Begins in the connective tissue (supports and connects the organs and structures of the body)
• Neuroendocrine (carcinoid) tumours (NETs) - Develop in neuroendocrine cells inside the small bowel. Neuroendocrine cells are in the nerves and glands within the small bowel and are responsible for making hormones, which are released into the bloodstream as part of normal body functioning
• Lymphoma - Form in lymph tissue within the small bowel. Lymph tissue is part of the body’s immune system

Small bowel cancer may present with no symptoms or with symptoms that may be similar in other conditions. This can make it difficult to diagnose.¹

Symptoms may include:¹

• Blood in stool or on the toilet paper
  
• Unexplained weight loss
• A lump in the abdomen
• Abdominal pain
• Nausea and vomiting
• Change in bowel habits including diarrhoea or constipation,
• Tiredness and weakness, caused by a low red blood cell count (anaemia)
• Yellowing of the skin and eyes (jaundice).

If you experience any of these symptoms or have concerns, please contact your general practitioner (GP).

The cause of small bowel cancer is not known. Several factors may increase the risk of developing small bowel cancer including:¹

• Genetic factors - There are some rare, inherited diseases that may put people at a higher risk of developing small bowel cancer
• Some small bowel cancers may be associated with autoimmune diseases such as Crohn’s disease and coeliac disease
• Eating large amounts of animal fat and protein, such as processed meat and red meat

A range of tests may be performed to analyse symptoms, to diagnose small bowel cancer. Following a physical examination, further tests may include:¹

• Blood tests - Are performed to measure white blood cells, red blood cells, and platelets. A liver function test may also be undertaken to measure chemicals in your liver. Sometimes a chromogranin A (CgA) blood test is performed as a way to help diagnose a carcinoid or other neuroendocrine tumour
• Endoscopy - This is where a tube with a camera on the end is used to look down your throat and into your stomach. You will be sedated during an endoscopy
• Capsule endoscopy - This is where you swallow a small capsule. Within the capsule is a very small camera that will take images of your digestive system. The camera will be passed in your stools after roughly 24 hours
• Imaging scans - These may include a computed tomography (CT) scan, magnetic resonance imaging (MRI) scan, positron emission tomography (PET) scan or a Barium X-ray.
• Biopsy - If your doctor sees anything unusual or abnormal, they may remove a small sample for closer examination.

Surgery is usually used to treat early-stage small bowel cancer. Your doctor will discuss with you the type of surgery you will have, depending on the location and stage of the tumour.

Chemotherapy is an approach to cancer therapy which involves the administration of medicine, usually orally or by injection, which is intended to kill cancer cells or minimise their growth and spread,

Chemotherapy can be used in conjunction with other cancer treatments,

Radiation therapy uses high energy rays to treat cancer and can be used at all stages of small bowel cancer.

• Immunotherapy is a type of treatment that is intended to help your immune system fight cancer
• There are different types of immunotherapy for cancer that work in different ways

All cancer treatments may have side effects. The type and severity of side effects will vary between individuals. You can ask your doctor for detailed information about the side effects which you may experience with any treatment recommended for you.