Aleukemic Extramedullary Blast Crisis as an Initial Presentation of Chronic Myeloid Leukemia with E1A3 BCR-ABL1 Fusion Transcript

Intern Med. 2022 Apr 1;61(7):1049-1054. doi: 10.2169/internalmedicine.8319-21. Epub 2021 Sep 11.

Abstract

Right neck swelling and pain occurred in a 49-year-old man. A Blood count showed a slight increase in platelet count without leukemoid reaction. After a biopsy of the cervical mass and bone marrow aspiration, a diagnosis of extramedullary blast crisis (EBC) of chronic myeloid leukemia (CML) was made. Fluorescence in situ hybridization (FISH) analysis showed a BCR-ABL1 fusion signal, but results of real-time polymerase chain reaction (RT-PCR) for major and minor BCR-ABL1 transcripts were negative. We identified a rare e1a3 BCR-ABL1 fusion transcript. Administration of dasatinib resulted in disappearance of the extramedullary tumor. This is the first reported case of CML-EBC with e1a3 transcript. An aleukemic extramedullary tumor can be the initial presentation of CML.

Keywords: BCR-ABL1; Philadelphia (Ph) chromosome; e1a3; extramedullary blast crisis.

Publication types

  • Case Reports

MeSH terms

  • Blast Crisis* / genetics
  • Blast Crisis* / pathology
  • Dasatinib / therapeutic use
  • Fusion Proteins, bcr-abl / genetics
  • Humans
  • In Situ Hybridization, Fluorescence
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive* / diagnosis
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive* / drug therapy
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive* / genetics
  • Male
  • Middle Aged

Substances

  • Fusion Proteins, bcr-abl
  • Dasatinib