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Rare Subtype May Have Prognostic Significance

Blood Cancer J; ePub 2017 Jul 14; Gong, et al

Though rare, the e1a2 transcript subtype appears to be a new high-risk factor for progression of chronic myeloid leukemia (CML), according to a study involving more than 2,300 individuals.

Participants had CML, carried a BCR-ABL1 subtype, and were receiving tyrosine kinase inhibitors. Investigators looked at the frequency of e1a2 transcript, risk of blastic transformation, treatment response, and outcomes. Among the results:

  • 98% had typical transcripts; most of the remainder had the e1a2 transcript.
  • Patients with the e1a2 transcript had a median time to complete cytogenetic remission (CCyR) of ~53 months, vs ~19 months for those with typical transcripts.
  • CCyR rates were 33% and 67%, respectively, at a median follow-up of 53 months.
  • The rates for achieving major molecular remission were 19% and 64%, respectively, at a median follow-up of ~60 months.
  • The differences remained significant when excluding patients with blast phase or additional chromosomal abnormalities (ACAs) initially, as well as those with unknown emerging time of ACAs.


Gong Z, Medeiros L, Cortes J, et al. Clinical and prognostic significance of e1a2 BCR-ABL1 transcript subtype in chronic myeloid leukemia. [Published online ahead of print July 14, 2017]. Blood Cancer J. doi:10.1038/bcj.2017.62.