Distinctive Flow Cytometric and Mutational Profile of Acute Myeloid Leukemia With t(8;16)(p11;p13) Translocation

Area of Science:

• Hematology
• Oncology
• Genetics

Background:

• Acute Myeloid Leukemia (AML) with t(8;16) is a rare and aggressive subtype.
• This specific AML subtype results in the KAT6A-CREBBP gene fusion.
• It presents significant diagnostic challenges due to its unique features.

Purpose of the Study:

• To investigate the immunophenotype and genomic features of AML with t(8;16).
• To identify diagnostic markers and common mutations in this rare AML subtype.

Main Methods:

• Retrospective review of 5 AML cases with t(8;16) from two medical centers.
• Analysis of immunophenotypic and genomic profiles using flow cytometry and next-generation sequencing.
• Cytogenetic and single nucleotide polymorphism microarray analysis.

Main Results:

• Four of five cases were therapy-related AML.
• Leukemic blasts exhibited bright CD45 expression and high side scatter, complicating initial identification.
• Commonly observed mutations included ASXL1 (2/4 cases) and FLT3-TKD (2/4 cases).
• t(8;16) was the sole cytogenetic abnormality in 3 patients; 7q deletion was found in one case.

Conclusions:

• AML with t(8;16) has a distinctive immunophenotype and morphology that pose diagnostic challenges.
• Mutations in ASXL1 or FLT3-TKD are frequently observed in this leukemia subtype.
• Understanding these features aids in the diagnosis and management of this rare AML.