Skin biopsy revealed proliferation of CD30(+) T cells consistent with lymphomatoid papulosis (LyP), whereas molecular analysis of peripheral blood mononuclear cells demonstrated the presence of the FIP1L1/PDGFRA fusion gene.     ///     Fip1-like 1/platelet-derived growth factor receptor-alpha (FIP1L1/PDGFRA)-positive hypereosinophilic syndrome is a rare disorder with a poor prognosis if untreated and for which treatment with imatinib mesilate is highly effective. 