A discussion of pediatric therapy-related acute myeloid leukemia with a rare t(8;16) translocation

Abstract

Abstract Introduction/Objective Secondary acute myeloid leukemia is a type of blood cancer that arises after a previous myeloid neoplasm or after exposure to chemotherapy. Certain genetic mutations and chromosomal abnormalities can occur as a result of said cytotoxic drug-related effects. Here, we discuss a case of secondary acute myeloid leukemia with a rare translocation following hemophagocytic lymphohistiocytosis Etoposide treatment in a 13-year-old female. After less than a year into her initial treatment, the patient presented to the emergency department with severe bone pain. A full hematologic workup was performed, including bone marrow biopsy, flow cytometry analysis, and subsequent genetic studies. A diagnosis of therapy-related acute myeloid leukemia was made. Genetic studies revealed a rare t(8;16) translocation which presents with a unique morphology and prognosis that will be discussed here. Methods/Case Report A 13-year-old female presented to the emergency department for evaluation of fever, myalgia, and swelling in her clavicle. The patient’s history was notable for hemophagocytic lymphohistiocytosis with subsequent Etoposide chemotherapy treatment which she received less than a year prior to her visit. CBC was notable for low white blood cell count, low hemoglobin, increased neutrophilic bands, and decreased lymphocytes. Given her past medical history and worsening pain without a clear reason, hematology was consulted. Results (if a Case Study enter NA) A blast count of 61.8% was reported via flow cytometry with the cells seen in the dim CD45+, moderate to bright side-scatter region, co-expressing CD4, CD14 (dim, heterogeneous), CD15, CD16 (dim), CD64, HLA-DR, and MPO. The bone marrow biopsy was described as hypercellular with the predominant cell type as blasts at 66.4%. Numerous hemophagocytic blasts were noted as well. Acute leukemia next generation sequencing panel revealed a t(8;16)(p11;p13.3) KATA6A::CREBBP fusion without other abnormalities in the evaluated genes. This workup as a whole rendered the diagnosis of acute myeloid leukemia with KAT6A::CREBBP. Conclusion Diagnosing acute myeloid leukemia with KATA6A::CREBBP is important for prognostic factors. Knowing the patient’s history regarding her prior chemotherapy with Etoposide is also imperative for distinguishing a de novo presentation of this rare subtype, versus a therapy-related myeloid neoplasm. The patient was started on chemotherapy for her acute myeloid leukemia shortly thereafter the diagnosis.