Objective: Acute promyelocytic leukemia (APL) with variant RARA translocation, eg, t(11;17), is not sensitive to all-trans retinoic acid and requires distinct chemotherapy. However, there are some leukemic entities that may mimic aspects of the clinical and/or laboratory picture of APL and cause confusion because of karyotype nomenclature. Therefore, recognition of such entities may be of therapeutic and prognostic significance.
Methods: We present 2 cases of acute myeloid leukemia (AML) with t(11;17) that were clinically concerning for APL based primarily on clinical presentation but were ultimately diagnosed as AML with monocytic differentiation.
Results: Both leukemias harbored KMT2A translocations, one located near but not involving RARA and the other with SEPT9.
Conclusion: In leukemias that clinically and/or immunophenotypically mimic APL, identification of specific gene translocations can lead to the correct diagnosis and may carry therapeutic/prognostic implications.
Keywords: RARA variants; acute myeloid leukemia; acute promyelocytic leukemia; fluorescence in situ hybridization; genetic sequencing; karyotype; molecular diagnostics.
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