Small bowel cancer can be diagnosed in different ways. You may see your GP about symptoms such as pain, weight loss or tiredness caused by anaemia. They will examine you and arrange some blood tests or x-rays. Your GP can then refer you to a specialist at the hospital for more tests and treatment if necessary.
https://www.macmillan.org.uk/cancer-information-and-support/bowel-cancer/small-bowel-cancer