Brief report: activity of imatinib in a patient with platelet-derived-growth-factor receptor positive malignant solitary fibrous tumor of the pleura.
Malignant solitary fibrous tumor (MSFT) of the pleura is a rare neoplasm, with unpredictable biologic behavior and a low sensitivity to chemotherapy. To the authors' knowledge, no other effective medical treatment is available for this disease. Imatinib mesylate is a tyrosine kinase inhibitor targeting the platelet-derived growth factor (PDGFR-alpha and PDGFR-beta), the BCR-ABL, and c-KIT receptors. We report the first evidence of the activity of imatinib in a symptomatic patient with a chemo- and radio-resistant advanced MSFT, who obtained a 21-months lasting major clinical benefit with a consistent reduction in tumor metabolism. Immunostaining of tumor cells demonstrated the positivity for PDGFR-alpha and PDGFR-beta and the absence of c-KIT over-expression, in the absence of c-KIT and PDGRFR mutations; all the cells strongly and diffusely expressed the ligand PDGF A in the cytoplasm. This profile suggests that the observed tumor response was mediated through the inhibition of the tyrosine kinase activity of PDGFR. Treatment with imatinib should be considered for patients with recurrent or unresectable MSFTs with PDGFR expression.
De Pas
Tommaso
T
New Drugs Development Unit, European Institute of Oncology, Milan, Italy. tommaso.de-pas@ieo.it
Toffalorio
Francesca
F
Colombo
Piergiuseppe
P
Trifirò
Giuseppe
G
Pelosi
Giuseppe
G
Vigna
Paolo Della
PD
Manzotti
Michela
M
Agostini
Monica
M
de Braud
Filippo
F
D000328:Adult; D001549:Benzamides; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D007124:Immunoenzyme Techniques; D010879:Piperazines / Q000627:therapeutic use*; D010997:Pleural Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000601:surgery; D011013:Pneumonectomy; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D011743:Pyrimidines / Q000627:therapeutic use*; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000037:antagonists & inhibitors / Q000378:metabolism*; D020797:Receptor, Platelet-Derived Growth Factor beta / Q000037:antagonists & inhibitors / Q000378:metabolism*; D054363:Solitary Fibrous Tumor, Pleural / Q000188:drug therapy* / Q000378:metabolism / Q000601:surgery; D014057:Tomography, X-Ray Computed
D001549:Benzamides; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases; D019009:Proto-Oncogene Proteins c-kit; D020796:Receptor, Platelet-Derived Growth Factor alpha; D020797:Receptor, Platelet-Derived Growth Factor beta