This is a phase II, multi-center (Israeli), open label, non-randomized trial for every patient with the specified tumors expressing c-kit or PDGFR. Expression of these kinases will be investigated in tumor samples obtained at the time of diagnosis or from the time of recurrent disease. Every patient with positive expression of either of the kinases will be evaluated for quantitative and qualitative evidence of disease prior to entry into the study, and if possible, no other treatment will be given concomitantly, to allow evaluation of the net effect of Glivec on tumor growth kinetics, searching for measurable evidence of response.

Glivec is supplied to the study investigators by Novartis Pharmaceutical. Patients will receive Glivec 400mg-800mg p.o./day for an exposure period of up to 12 months provided that in the opinion of the investigator the patient is benefiting from treatment with Glivec, and in the absence of any safety concern. For patients with brain tumors who are not receiving concomitant enzyme inducing anti-convulsant drugs, the recommended dose of Glivec is 800mg/day.