Acute myeloid leukemia with NUP98::RARG rearrangement: a case report and review of the relevant literature

Abstract

We herein report a rare case of acute myeloid leukemia (AML) with t(11;12)(p15;q13) and NUP98::RARG, which seems to be involved in the development of AML. The morphological features were similar to those of classic acute promyelocytic leukemia (APL), but unlike classic APL, this leukemia was resistant to treatment with all-trans retinoic acid (ATRA). We decided to use standard chemotherapy for AML with monitoring of minimal residual disease (MRD) by qualitative reverse transcriptase-polymerase chain reaction (RT-PCR) analysis for NUP98::RARG mRNA. Although MRD disappeared after induction chemotherapy, it later reappeared, and hematological relapse occurred during subsequent chemotherapies. The patient received haploidentical hematopoietic stem cell transplantation while not in remission and achieved a second molecular remission. However, relapse occurred 4 months after transplantation. The specific mechanism of ATRA resistance in this unique case of AML remains unclear, and no standard treatment has been determined. This is the first case report of AML with NUP98::RARG rearrangement in Japan. Qualitative RT-PCR analysis for NUP98::RARG mRNA was helpful for the accurate diagnosis and evaluation of MRD to choose an adequate treatment for this type of AML.

Keywords: Acute promyelocytic leukemia; Haploidentical transplantation; NUP98; RARG.