FLT3 mutation and response to intensive chemotherapy in young adult and elderly patients with normal karyotype.

The prognostic impact of FLT3 mutations on the outcome of patients with diploid AML, treated with intensive chemotherapy, was analyzed. In 176 patients, the frequency of single ITD was 30% (<61 years: 37%, >60 years: 23%), single D835 mutation 2.3%, and both 2.3%. There was no association between ITD and CR rate. ITD-positive patients <61 years had a higher frequency of resistant disease. ITD was adversely associated with CR duration and survival in both younger and elderly patients treated with comparable chemotherapy but the effect was less in the elderly. Presence of both ITD and D835 heralded the least favorable outcome.