Abstract
A 19-month-old female with a right temporal bone tumor was diagnosed
with diffuse large B-cell lymphoma by tumor biopsy. Leukemic conversion
occurred after chemotherapy for mature B-cell lymphoma. Additional
chemotherapy was unsuccessful and resulted in death of the patient owing
to disease progression. We detected the KMT2A-MLLT3 fused
transcript in the bone marrow of the patient with primary and recurrent
cancer. RNA sequencing of the bone marrow with recurrent cancer showed
similarities with KMT2A-rearranged leukemia, such as
overexpression of MEIS1 and MEF2C, which was attributable
to the aggressive course.