FLT3 mutations in myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML).

6597 Background: FLT3 mutations occur in one third of acute myeloid leukemia (AML) patients (pts) and predict poor outcome. The incidence and impact of FLT3 in MDS/ CMML is unknown. Methods: We conducted a retrospective review at MDACC to identify FAB MDS/ CMML pts with FLT3 mutations at diagnosis. Results: From 1996 to 2010; 2052 MDS/ CMML pts had mutation analysis. 45 (2.2%) had FLT3 mutations (internal tandem duplication-ITD or D835) at diagnosis. 29 pts had MDS and 16 had CMML. Median (Med) age was 64 years (21 to 83) and 69% were males. FAB groups: 3 pts with refractory anemia (RA), 11 pts with refractory anemia-excess blasts (RAEB), 18 pts with refractory anemia-excess blasts in transformation (RAEB-T) and 13 pts with CMML. IPSS: 3 in Low (7%), 16 in Int-1 (36%), 11 in Int-2 (24%), and 15 in High (33%). Med white count, hemoglobin, platelet count and marrow blast percent at diagnosis were 5.2 x 109/l (1.2 to 211), 10.0 g/l (6.8 to 14.9), 78 x 109/l (8 to 429), and 14% (1 to 28), respectively. FLT3 I...