 A small subgroup of patients with hypereosinophilic syndrome (HES) demonstrates imatinib-sensitive fusion transcript-the FIP1L1-PDGFRA (F/P+).     ///    Clinical characteristics of patients with chronic eosinophilic leukaemia (CEL) harbouring FIP1L1-PDGFRA fusion transcript--results of Polish multicentre study..     ///    "In this paper, we screened 77 patients to estimate the frequency of FIP1L1-PDGFRA transcript among patients with unexplained, long-term hypereosinophilia exceeding 1.5 x 10(9)/L and to analyse the clinical and serological features in F/P+ CEL population. "    ///    The FIP1L1-PDGFRA chimeric protein was detectable in 16 (14 males and 2 females) out of 77 examined HES patients (20%) by RT-PCR. 