PML/RAR alpha(+) hypergranular acute promyelocytic leukemia (M3) developing into an M3 acute myelocytic leukemia without PML/RAR alpha.

The case of an adult with PML/RARalpha(+) hypergranular acute promyelocytic leukemia (M3) that evolved into a rapidly fatal M3 acute myelocytic leukemia without PML/RARalpha after a complete and molecular remission had been achieved, is presented. Only 7 such cases have been published in the literature. The possible origin of this either leukemic relapse or secondary malignancy is briefly discussed, focusing on the fact that this diagnosis could only be defined by adequate molecular biology studies in the leukemic cells.