KIR2DL1 and acute myeloid leukemia: The authors of the above-mentioned study proposed that the impaired cytotoxicity associated with a lower expression of these receptors can represent the risk factor of secondary malignancies.42 In studies presented by Mi et al,43 in patients with MDS and AML, CD158a expression was significantly lower than in the control group, whereas there was no difference in the CD158b expression.