Juvenile myelomonocytic leukemia with t(3;5)(q25;q35), Auer rods and marked myelodysplasia.
Juvenile myelomonocytic leukemia (JMML) is a rare aggressive childhood leukemia characterized by an excess proliferation of cells of granulocytic and monocytic lineages. The WHO classifies JMML with the myelodysplastic/myeloproliferative neoplasms. Myelodysplasia in JMML is usually minimal to mild. Auer rods have never been reported in JMML. We present a 2-year-old boy with splenomegaly, leukocytosis, thrombocytopenia, anemia, and excess myeloblasts with easily seen Auer rods, and marked dysgranulopoiesis and dyserythropoiesis. Conventional cytogenetic analysis showed a sole abnormality of t(3;5)(q25;q35). Microarray analysis showed a terminal 21 Mb region of copy-neutral loss of heterozygosity on 19q. Disease-related somatic NRAS mutation was detected. This case represents an unusual JMML with Auer rods and marked myelodysplasia. These unusual histopathologic features may be related to the t(3;5)(q25;q35). A t(3;5) with variable breakpoints has been reported in a small proportion of acute myeloid leukemias and myelodysplastic syndromes. To our knowledge, this is the first JMML case reported with this translocation.
Pathology, research and practice
Child, Preschool; Chromosomes, Human, Pair 3; Chromosomes, Human, Pair 5; Humans; Leukemia, Myelomonocytic, Juvenile; Male; Translocation, Genetic
19q LOH; Auer rods; Juvenile myelomonocytic leukemia; Myelodysplasia; t(3; 5)
Li W, Cooley LD, August K. Juvenile myelomonocytic leukemia with t(3;5)(q25;q35), Auer rods and marked myelodysplasia. Pathol Res Pract. 2018;214(6):919-923. doi:10.1016/j.prp.2017.11.024