Rearrangements in Leukemia Patients: A Case Series From a Single Institution.

Background: The three best-known rearrangements found in leukemia (, and ) are associated with treatment resistance and poor prognosis. Mouse experiments have shown that rearrangements alone are insufficient for leukemogenesis; therefore, the identification of concurrent mutations is important for accurate assessment and tailored patient management. Here, we characterized the demographic characteristics and concurrent mutations in patients harboring rearrangements.

Methods: To identify patients with rearrangements, RNA-sequencing results of diagnostic bone marrow aspirates were retrospectively studied. Concurrent targeted next-generation sequencing results, patient demographics, karyotypes, and flow cytometry information were also reviewed.

Results: In total, 11 patients harboring rearrangements were identified, among whom four had , three had , and four had . All -positive patients were diagnosed as having AML. In patients carrying and , T-lymphoblastic leukemia was the most common diagnosis (50%, 4/8). Concurrent gene mutations were found in all cases. mutations were the most common (45.5%, 5/11), followed by (27.3%, 3/11), (27.3%, 3/11), -internal tandem duplication (27.3%, 3/11), (18.2%, 2/11), and (18.2%, 2/11) mutations. Two patients represented the second and third reported cases of -positive AML.

Conclusions: We examined the characteristics and concurrent test results, including gene mutations, of 11 leukemia patients with rearrangement. We hope that the elucidation of the context in which they occurred will aid future research on tailored monitoring and treatment.