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

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.