Gastrointestinal stromal tumours (GIST) are mesenchymal tumours of the gastrointestinal tract. They are rare and represent about 1% of all malignancies in this area. They can occur anywhere in the gastrointestinal tract. Establishing a diagnosis is challenging as GIST usually do not show any specific signs or symptoms. Characteristically, they express the CD117 protein which is also an important target for treatment with imatinib mesylate. The treatment of choice for GIST is radical resection which is the only mode of treatment with a chance of survival. After the resection, there is a great chance of recurrent disease which is why new ways of treatment with tyrosine kinase inhibitors are being researched lately. In this article, we present a case report of a patient with anemia and was correctly diagnosed and treated for GIST after undergoing a extensive diagnostic approach to this disease.