PDGFRalpha/FIP1L1-positive chronic eosinophilic leukemia presenting with retro-orbital localization: efficacy of imatinib treatment.

Abstract

INTRODUCTION:

The fusion protein between the platelet-derived growth factor receptor alpha (PDGFRalpha, P) gene and the Fip1-like1 (FIP1L1, F) may be identified in 14 to 60% of HES and it indicates a clonal hypereosinophilic syndrome called F/P-positive CEL. We herein report a case of F/P-positive CEL with retro-orbital localization, who was successfully treated with imatinib.

CASE REPORT:

A 53-year-old male presented an absolute eosinophil count of 25,000/mm(3), anemia (Hb 10.2 g/dl) and a moderate increase in the platelet count (571,000/mm(3)). A clinical examination revealed left exophthalm, associated with diffuse hypoesthesia and diplopia. A CT scan of orbits showed a lesion located in the lachrymal fossa of the left orbit with intra- and extra-conical extension. Molecular analysis excluded the presence of bcr/abl transcript while a F/P fusion tyrosine kinase signal was documented. Imatinib mesylate (IM) was started and, after 7 days of treatment eosinophil count significantly declined along with a dramatic reduction of the left exophthalm. IM dosage was increased up to 300 mg/day. The drug was well tolerated with an initial modest haematological toxicity. The left exophthalm, as well as hypoesthesia and diplopia, disappeared after IM therapy. MRI showed a clear reduction of the intra- and extra-conical growth process. BM molecular signal of the F/P fusion gene resulted undetectable after 4 weeks of treatment.

CONCLUSION:

In our case, the diagnosis of FIPIL1-PDGFRA-positive CEL and IM therapy has allowed the patient to experience an excellent clinical therapeutic result, avoiding surgical treatment of the retro-orbital mass.

• Authors: Ernesto Vigna, Eugenio Lucia, Massimo Gentile, Carla Mazzone, Maria Grazia Bisconte, Carlo Gentile, Antonio Armentano, Emanuela Ottaviani, Michela Rondoni, Giovanni Martinelli, Fortunato Morabito
• Journal: Cancer chemotherapy and pharmacology (Cancer Chemother Pharmacol) Vol. 61 Issue 4 Pg. 713-6 (Apr 2008) ISSN: 0344-5704 [Print] Germany
• PMID: 17549478 (Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents
• Benzamides
• Oncogene Proteins, Fusion
• Piperazines
• Pyrimidines
• mRNA Cleavage and Polyadenylation Factors
• Imatinib Mesylate
• FIP1L1-PDGFRA fusion protein, human
• Receptor, Platelet-Derived Growth Factor alpha

Topics

• Antineoplastic Agents (therapeutic use)
• Benzamides
• Humans
• Hypereosinophilic Syndrome (drug therapy, genetics)
• Imatinib Mesylate
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Oncogene Proteins, Fusion (metabolism)
• Orbital Neoplasms (drug therapy, genetics)
• Piperazines (therapeutic use)
• Pyrimidines (therapeutic use)
• Receptor, Platelet-Derived Growth Factor alpha (metabolism)
• Reverse Transcriptase Polymerase Chain Reaction
• Tomography, X-Ray Computed
• mRNA Cleavage and Polyadenylation Factors (metabolism)