Acute Lymphocytic Leukemia With KMT2A-ELL Fusion Mutation in a Patient With Untreated Chronic Lymphocytic Leukemia: A Case Report and Literature Review

Background: The concurrent of chronic lymphocytic leukemia (CLL) and acute myeloid leukemia (AML) in a patient is a rare situation, and has caused obstacles in clinical management. Case presentation: In the current study, we described a 64-year old female who was characterized by intermittent fatigue, edema of both lower limbs, dyspnea, and occasionally fever up to 39°C. The admission blood routine detections and the flow cytometry showed the patient was impaired by both CLL and AML. In RT-qPCR molecular detection, KMT2A-ELL fusion gene t (11:10) (q23:p13.1) was detected, which was verified by FISH detections. The next-generation sequencing (NGS) revealed a missense mutation of p.V157F in the coding sequence of TP53 gene, and frameshift mutations of p.V220fs and p.A382fs in the coding sequence of WT1. Conclusions: Collectively, the patient reported in this case was simultaneously impaired by CLL and AML. Our findings also inferred that the concurrent of CLL and AML might be attributed to the fusion mutation in KMT2A-ELL gene.