Scholarlink

<p>Myeloid/Lymphoid Neoplasms with Eosinophilia and Tyrosine Kinase Gene Fusions (MLN-eo-TK) represent a distinct and heterogeneous group of hematologic malignancies characterized by recurrent gene fusions involving tyrosine kinases, such as <i>PDGFRA</i>,<i> PDGFRB</i>,<i> FGFR1</i>,<i> JAK2</i>,<i> FLT3</i>,<i> ETV::ABL1</i> and other partner genes/variants. Among these, gene rearrangements involving <i>PCM1::JAK2</i> are rare and may present diagnostic challenges, particularly when manifesting as acute lymphoblastic leukemia (ALL). We describe a case of a patient who presented with B-cell acute lymphoblastic leukemia (B-ALL) with a <i>JAK2</i> rearrangement. After the induction therapy, strong myeloid proliferation in bone marrow without evidence of residual lymphoblasts was observed and <i>JAK2</i> rearrangement was recognized to be a consequence of translocation t(8;9)(p22;p24)] resulting in <i>PCM1::JAK2</i> fusion. This finding indicated the presence of an underlying chronic myeloid/lymphoid neoplasm, meeting criteria for MLN-eo-TK. Following an inadequate response to standard chemotherapy, salvage regimens incorporating targeted agents (JAK2 and BCL-2 inhibitors) and allogeneic bone marrow transplantation were administered, all of which unfortunately resulted in short-lived clinical benefit. The case highlights the importance of distinguishing de novo lymphoid malignancies from MLN-eo-TK, especially when <i>JAK2</i> rearrangements are detected. Recognition of the clonal myeloid component during or after lymphoid-directed therapy has important diagnostic and therapeutic implications, supporting the use of targeted JAK2 inhibition in addition to standard chemotherapy.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

A case report and a literature review of Myeloid/Lymphoid Neoplasm with Eosinophilia and PCM1::JAK2 rearrangement representing as B-cell acute lymphoblastic leukemia B-ALL

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年1月14日

查看全文
  • Luka Čemažar,
  • Klara Šlajpah,
  • Njetočka Gredelj Šimec,
  • Helena Podgornik

摘要

Myeloid/Lymphoid Neoplasms with Eosinophilia and Tyrosine Kinase Gene Fusions (MLN-eo-TK) represent a distinct and heterogeneous group of hematologic malignancies characterized by recurrent gene fusions involving tyrosine kinases, such as PDGFRA, PDGFRB, FGFR1, JAK2, FLT3, ETV::ABL1 and other partner genes/variants. Among these, gene rearrangements involving PCM1::JAK2 are rare and may present diagnostic challenges, particularly when manifesting as acute lymphoblastic leukemia (ALL). We describe a case of a patient who presented with B-cell acute lymphoblastic leukemia (B-ALL) with a JAK2 rearrangement. After the induction therapy, strong myeloid proliferation in bone marrow without evidence of residual lymphoblasts was observed and JAK2 rearrangement was recognized to be a consequence of translocation t(8;9)(p22;p24)] resulting in PCM1::JAK2 fusion. This finding indicated the presence of an underlying chronic myeloid/lymphoid neoplasm, meeting criteria for MLN-eo-TK. Following an inadequate response to standard chemotherapy, salvage regimens incorporating targeted agents (JAK2 and BCL-2 inhibitors) and allogeneic bone marrow transplantation were administered, all of which unfortunately resulted in short-lived clinical benefit. The case highlights the importance of distinguishing de novo lymphoid malignancies from MLN-eo-TK, especially when JAK2 rearrangements are detected. Recognition of the clonal myeloid component during or after lymphoid-directed therapy has important diagnostic and therapeutic implications, supporting the use of targeted JAK2 inhibition in addition to standard chemotherapy.