title: MLL duplication in a pediatric patient with B-cell lymphoblastic lymphoma.
abstract: Lymphoblastic lymphoma is the second most common type of non-Hodgkin lymphoma seen in children. Approximately, 90% of lymphoblastic lymphomas arise from T cells, with the remaining 10% being B-cell-lineage derived. Although T-cell lymphoblastic lymphoma most frequently occurs in the anterior mediastinum (thymus), B-cell lymphoblastic lymphoma (B-LBL) predominates in extranodal sites such as skin and bone. Here, we describe a pediatric B-LBL patient who presented with extensive abdominal involvement and whose lymphoma cells displayed segmental duplication of the mixed lineage leukemia (MLL) gene. MLL duplication/amplification has been described primarily in acute myeloid leukemia and myelodysplastic syndrome with no published reports of discrete MLL duplication/amplification events in B-LBL. The MLL gene duplication noted in this case may represent a novel mechanism for tumorigenesis in B-LBL.
authors: Department of Pediatrics, Duke University, Durham, NC, USA. david.vanmater@duke.edu
authors: David Van
authors: DV
authors: Mater
authors: Barbara K
authors: BK
authors: Goodman
authors: Endi
authors: E
authors: Wang
authors: Ana M
authors: AM
authors: Gaca
authors: Daniel S
authors: DS
authors: Wechsler
mesh_terms: D002648:Child; D020732:Cytogenetic Analysis; D005434:Flow Cytometry; D020440:Gene Duplication; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D008297:Male; D051788:Myeloid-Lymphoid Leukemia Protein / Q000235:genetics*; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy / Q000235:genetics*; D014057:Tomography, X-Ray Computed
chemical_list: C497422:KMT2A protein, human; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase