title: Transformation of an Unclassified Myeloproliferative Neoplasm with a Rare BCR-JAK2 Fusion Transcript Resulting from the Translocation (9;22)(p24;q11).
abstract: BCR-ABL1 negative myeloproliferative neoplasms (MPNs) are known to contain alterations of the tyrosine kinase JAK2 (located on 9p24) that result in constitutive activation of the encoded protein. JAK2 fusions are reported in acute and chronic leukemias of myeloid and lymphoid phenotypes. Here, we report an unclassified case of MPN (MPN-U) showing a t(9;22)(p24;q11), which generates a BCR-JAK2 fusion gene by fusing the BCR at intron 13 to JAK2 at intron 17 on the derivative chromosome 22. Most reported JAK2 fusions cases reveal an aggressive clinical course and long-term remissions have only been achieved after allogeneic stem cell transplantation (ASCT). To the best of our knowledge, this is the thirteenth case reported worldwide to describe a BCR-JAK2 fusion transcript in MPN-U. The present report revealed a sustained complete clinical, hematologic, and cytogenetic remission 35 months after diagnosis and ~24 months after ASCT. Regarding BCR-ABL1  negative MPN patients this case report provides strong support for a role of JAK2 activation in the oncogenesis and suggests a possible diagnostic and therapeutic target that should be investigated.
authors: Department of Clinical Hematology, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; Blood and Marrow Transplant Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: A N
authors: AN
authors: Chamseddine
authors: Molecular and Genetic Laboratory Department, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: P
authors: P
authors: Etancelin
authors: Molecular and Genetic Laboratory Department, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; INSERM U918 Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: D
authors: D
authors: Penther
authors: Molecular and Genetic Laboratory Department, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; INSERM U918 Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: F
authors: F
authors: Parmentier
authors: Molecular and Genetic Laboratory Department, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: C
authors: C
authors: Kuadjovi
authors: Department of Clinical Hematology, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; Blood and Marrow Transplant Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: V
authors: V
authors: Camus
authors: Department of Clinical Hematology, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; Blood and Marrow Transplant Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: N
authors: N
authors: Contentin
authors: Department of Clinical Hematology, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; Blood and Marrow Transplant Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: P
authors: P
authors: Lenain
authors: Molecular and Genetic Laboratory Department, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; INSERM U918 Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: C
authors: C
authors: Bastard
authors: Department of Clinical Hematology, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; Blood and Marrow Transplant Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; INSERM U918 Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: H
authors: H
authors: Tilly
authors: Department of Clinical Hematology, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; Blood and Marrow Transplant Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France ; INSERM U918 Unit, Henri Becquerel Cancer Center, 1 rue d'Amiens, 76038 Rouen, France.
authors: F
authors: F
authors: Jardin