Successful treatment of myeloid neoplasms associated with PDGFRA rearrangement with imatinib mesylate.

Hypereosinophilic syndromes (HES) constitute a rare and heterogeneous group of disorders, defined as persistent and marked blood eosinophilia associated with evidence of eosinophil-induced organ damage. Cardiac dysfunction is the most frequent result of end-organ damage and is the major cause of morbidity and mortality among patients with HES. Despite patients with FIP1-like-1-platelet-derived growth factor alpha (FIP1L1-PDGFRA) associated HES (myeloid neoplasms associated with PDGFRA rearrangement) have been shown to respond to low-dose imatinib with a complete and durable hematological and cytogenetic remission, influences of imatinib on clinical manifestations related to hypereosinophilia heart involvement are variable. Here we describe the case of a young male patient with severe heart involvement who had a prompt, clinical and hematological complete remission following administration of imatinib. However, as endomyocardial fibrosis and related loss of function are deteriorated after initiation of imatinib therapy, valvular replacement and tricuspid annuloplasty had to perform to restore his heart function. Our finding concurs with recent reports that severe heart involvement was irreversible with imatinib treatment.