[Clinical and genetic features of a patient with myeloid neoplasm in association with PDGFRA and EVI1 gene rearrangements].

ABSTRACT

OBJECTIVE: Todelineate the clinical and genetic features of a patient with myeloproliferative neoplasm (MPN) in association with PDGFRA and EVI1 genes rearrangements. METHODS: Clinical data of the patient was collected. Conventional cytogenetics, fluorescence in situ hybridization (FISH) and nested PCR were carried out for the patient. RESULTS: The patient has featured recurrent rash, joint pain, and intermittent fever. Laboratory tests showed hyperleukocytosis and marked eosinophilia. Physical examination revealed splenomegaly. His karyotype was 46,XY,t(3;5)(q26;q15)[6]/46,XY[10]. FISH assay showed that both PDGFRA and EVI1 genes were rearranged. Molecular studies of the mRNA suggested that there was a in-frame fusion between exon 12 of the PDGFRA gene and exon 9 of the FIP1L1 gene. Imatinib was initiated at a dosage of 200 mg, and after 10 months, the signal of the FIP1L1-PDGFRA fusion gene was undetectable in bone marrow sample. However, the expression of EVI1 mRNA was stable, with no significant difference found between the patient and 10 healthy controls. CONCLUSION: MPN in association with PDGFRA and EVI1 genes rearrangements have unique clinical and genetic features. Genetic testing is helpful for early diagnosis. Imatinib may be effective for the treatment.