Reduce size of tumour - CD117 Negative

i am suffering from tumour in my abdomen,which has been identified as gist by couple of doctors of various hospitals.this tumour is CD117 Negative and blood vessels are also stuck into it.Now the doctors say that first the size of the tumour has to be reduced then only it can be operated.As regard to reduction of size they don't have any other treatment except kemotherapy.For kemotherapy also they are not sure that it can give a satisfactory result.
Please help ASAP.

[CalGal]

There is a c-kit tyrosine kinase inhibitor imatinib (Glivec/Gleevec) that has been used and found to be helpful in treating GISTs. However, whether this can be used may depend on the phenotype - so that may need to be addressed first. I'm not sure whether anyone except a specialist will know what the treatment duration should be or if this could be used. In those who GISTs are resistant to this drug, studies have suggested that the multiple tyrosine kinase inhibitor sunitinib (marketed as Sutent) may be effective.

But again, you're back to the fact that you need to be working with someone who is very familiar with GISTs and with the current drugs. No one will be able to tell you definitively, however.