Gastrointestinal Stromal Tumours

Depending on the symptoms (e.g. gastrointestinal bleeding or an abdominal mass), your doctor may use any of the following procedures to assess and diagnose a GIST tumour.

1. CT scan
This is usually the imaging method of choice to evaluate an abdominal mass to see where it arises from, the extent of the tumour, and to see if there is presence of disease spread. However, it may be difficult to determine the organ of origin when the mass is very large.


2. Endoscopy
This is usually the procedure of choice in patients who present with gastrointestinal bleeding. - This is a day surgery procedure performed under sedation whereby a long, thin flexible video camera is inserted into your digestive tract. A standard biopsy (obtaining tissue samples) may be inconclusive as the GIST originates from a deeper layer of the wall of the digestive tract and regular biopsies may be too superficial.


3. Endoscopic ultrasound
This is used to further characterise a GIST by identifying its layer of origin within the walls of the digestive tract. It also enables targeted, deeper tissue biopsies of the tumour. A diagnostic biopsy may not always necessary in the treatment of a GIST.

Your doctor may also order other investigations if deemed appropriate.