Philadelphia chromosome‐positive mature B‐cell (Burkitt cell) leukaemia

Abstract

Summary. Philadelphia chromosome-positive (Ph + ) acute leukaemia usually shows lymphoblastic morphology and a B-precursor phenotype. The bone marrow aspirate of a 9-year-old boy showed a L3 blast cell morphology in 90% of cells; immunophenotyping revealed a mature B-blast population. The translocation t(9;22) (q34;q11) was seen in 45 out of 50 metaphases, and expression of the corresponding bcr1/abl fusion transcripts, but no IgH/myc co-localization or splitting of c-myc, was demonstrated. Chemotherapy according to the Berlin-Frankfurt-Munster non-Hodgkin's lymphoma (NHL-BFM 95) protocol with maintenance according to the BFM acute lymphoblastic leukaemia (ALL-BFM 90) protocol resulted in continuing complete remission of 54 months. The occurrence of Ph + Burkitt's leukaemia might reflect multiple-step cancer development.

Precursor B-Cell Acute Lymphoblastic Leukemia/Lymphoma with L3 Morphology, Philadelphia Chromosome, MYC Gene Translocation, and Coexpression of TdT and Surface Light Chains: A Case Report

“…Coexpression of surface light chains and TdT has been previously reported in ALL [2, 3]. Presence of the Philadelphia chromosome, although described rarely in mature lymphomas [4], further supports the diagnosis of ALL and portends a worse prognosis. A MYC gene rearrangement is most frequently associated with Burkitt lymphoma yet has been reported in other mature and immature B-cell neoplasms [5, 6].…”