What are the symptoms of gastrointestinal stromal tumour?

A gastrointestinal stromal tumour, or GIST, is a tumour that develops in the supporting tissues of the digestive tract, often in the stomach or small intestine. A small tumour may cause no symptoms and can be found during an examination for another reason. As it grows, it can bleed into the digestive tract, causing visible blood in the stool or black, tar-like stool, and may contribute to tiredness from blood loss. It can also cause abdominal pain, a lump, nausea, vomiting, early fullness, or changes in eating. These symptoms have several possible causes and do not establish a diagnosis on their own.

Arrange medical review for ongoing abdominal pain, unexplained fullness, recurrent nausea or vomiting, black stools, visible blood in the stool, or tiredness without a clear explanation. The clinician may ask about digestion and bleeding, examine the abdomen, and arrange blood tests or imaging. Endoscopy or a biopsy may be used when a mass needs closer assessment. If GIST is diagnosed, treatment can include tumour removal surgery or targeted therapy depending on its location and features.

Seek urgent help for vomiting blood, black stools with weakness or dizziness, heavy rectal bleeding, fainting, severe or rapidly worsening abdominal pain, persistent vomiting, or a swollen abdomen with inability to pass stool or gas. These symptoms can signal significant bleeding or blockage and need immediate evaluation.

Ask what could explain the pain or bleeding, which tests are needed, and whether a biopsy is appropriate. If a GIST is found, ask where it began, whether it can be removed, how targeted therapy works, and which symptoms should lead you to seek urgent help.