FIP1L1-PDGFRA in eosinophilic disorders: Prevalence in routine clinical practice, long-term experience with imatinib therapy, and a critical review of the literature

A. Pardanani, R. P. Ketterling, C. Y. Li, M. M. Patnaik, A. P. Wolanskyj, M. A. Elliott, J. K. Camoriano, J. H. Butterfield, G. W. Dewald, A. Tefferi

Research output: Contribution to journalArticle

107 Scopus citations


We previously studied clinico-pathologic features of 89 consecutive adult patients with moderate-to-severe eosinophilia, and reported a FIP1L1-PDGFRA prevalence of 12%. In that series, all 11 FIP1L1-PDGFRA+ patients receiving imatinib achieved a complete response. We now extend our observations through a study of 741 unselected patients with eosinophilia for FIP1L1-PDGFRA, and present longer term follow up data for the imatinib-treated cohort. We also include data for three previously unreported FIP1L1-PDGFRA+ patients. Among the 741 requests, only 21 (3%) were found to carry the FIP1L1-PDGFRA mutation. While all 14 FIP1L1-PDGFRA+ patients receiving imatinib achieved a complete response, the 4 patients who attempted to discontinue imatinib all relapsed. We also find that it is possible to maintain patients in clinical remission with an empirically derived schedule of low-dose (50-100 mg), intermittent (once daily to once weekly) imatinib. Lastly, we present a comprehensive review of the literature pertaining to FIP1L1-PDGFRA in order to address several key aspects of this mutation from a clinical standpoint.

Original languageEnglish (US)
Pages (from-to)965-970
Number of pages6
JournalLeukemia Research
Issue number8
StatePublished - Aug 1 2006



  • Eosinophilia
  • Imatinib
  • Mutation
  • Prevalence

ASJC Scopus subject areas

  • Hematology
  • Oncology
  • Cancer Research

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