CD34 and leukemia: The incidences of LTLS in the traditional high risk groups were as follows: age >60 years 28.8%, primary AML 26.8%, secondary AML 25%; WBC >100x109/L 50%, LDH >2xULN 21.6%, CD34+ leukemias 16.3%, NPMI 27.2% and FLT3 gene mutation 33.3%.