An ETV6-ABL1 fusion in a patient with chronic myeloproliferative neoplasm: Initial response to Imatinib followed by rapid transformation into ALL.
We report the case of a 26 year-old patient presenting with a persistent leukocytosis and CML-like marrow but no evidence of a BCR/ABL1 fusion. Molecular cytogenetics revealed that a portion of the ETV6 locus was inserted into the ABL1 locus. An ETV6/ABL1 fusion transcript could subsequently be confirmed. The patient was started on imatinib and went into complete cytomorphological remission. QRT-PCR measurements showed a 4 log reduction of the ETV6/ABL1 fusion. 15 months later, the disease transformed into ALL and the patient expired. Thus, an ETV6/ABL1 fusion positive MPN has the potential to transform very rapidly into ALL.
Department of Molecular Medicine and Pathology, The University of Auckland, Auckland, New Zealand.
Purvi M
PM
Kakadia
Department of Internal Medicine, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München (LMU), Munich, Germany.
Ralf
R
Schmidmaier
Department of Internal Medicine, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München (LMU), Munich, Germany.
Andreas
A
Völkl
Laboratory for Leukemia Diagnostics, Department of Medicine III, University of Munich Hospital, Campus Grosshadern, Munich, Germany.
Irene
I
Schneider
Laboratory for Leukemia Diagnostics, Department of Medicine III, University of Munich Hospital, Campus Grosshadern, Munich, Germany.
Natalia
N
Huk
Laboratory for Leukemia Diagnostics, Department of Medicine III, University of Munich Hospital, Campus Grosshadern, Munich, Germany.
Stephanie
S
Schneider
Center for Human Genetics, Philipps University, Marburg, Germany.
Gerda
G
Panzner
Center for Human Genetics, Philipps University, Marburg, Germany.
Ulrike
U
Neidel
Center for Human Genetics, Philipps University, Marburg, Germany.
Barbara
B
Fritz
Laboratory for Leukemia Diagnostics, Department of Medicine III, University of Munich Hospital, Campus Grosshadern, Munich, Germany.
Karsten
K
Spiekermann
Department of Molecular Medicine and Pathology, The University of Auckland, Auckland, New Zealand.
Stefan K
SK
Bohlander
ALL; CML; ETV6/ABL1 fusion; MRD assay; TKI treatment