In the group of 89 patients, whose initial tumor mutational status was evaluated, 58.4% of GISTs had an exon 11 KIT mutation, 16.9% had an exon 9 KIT mutation, 13.5% had PDGFRA gene mutation (11 of 12 cases had D842V mutation) and in 11.2% of tumors we have not detected any mutations (wild-type). Here, PDGFRA is linked to neoplasm.