Imatinib mesylate in the treatment of c-kit-positive acute myeloid leukemia: is this the real target?

We report on our experience in 36 cases of c-kit-positive AML, not amenable to conventional chemotherapy, who were treated with imatinib. Median dose was 600 mg/d, for a median of 31 days. Six patients died while on therapy, and other 15 died during follow-up, mainly for disease progression. No patient achieved a complete or a partial remission, in only 2 cases disease was stable. No significant “in vivo” inhibition of c-kit was found, thus suggesting that multiple gene aberrations are responsible for leukemic proliferation, and that c-kit activity may be useful but not necessary for AML blast survival and proliferation.