PML and acute myeloid leukemia: According to the current WHO criteria, the presence of t(15;17)(q22;q12), hence of the promyelocytic leukemia protein (PML)-RARA gene fusion, allows an AML to be classified as APL, but other variant RARA translocations with other partner genes are not only considered distinct, but not all have typical APL features and indeed, some patients show resistance to ATRA (Arber et al., 2016).