gms | German Medical Science

27th German Cancer Congress Berlin 2006

German Cancer Society (Frankfurt/M.)

22. - 26.03.2006, Berlin

First patients with NF1 and malignant peripheral nerve sheath tumors treated with imantinib. Start of an open labelled phase II study

Meeting Abstract

  • corresponding author presenting/speaker Victor-Felix Mautner - Department of Maxillofacial Surgery, University Hospital Hamburg, 20246 Hamburg, Germany, Deutschland
  • Nikola Holtkamp - Institute for Neuropathology, Charité University Hospital Berlin, 13353 Berlin, Germany
  • R. Straeter - Department of Pediatric Haematology, University Hospital Münster, 48149 Münster. Germany
  • Marcos Tatagiba - Department of Neurosurgery, University Hospital Tübingen, 72076 Tübingen, Germany
  • Reinhard Friedrich - Department of Maxillofacial Surgery, University Hospital Hamburg, 20246 Hamburg, Germany
  • Maike de Wit - Department of Oncology; University Hospital Hamburg, 20246 Hamburg, Germany

27. Deutscher Krebskongress. Berlin, 22.-26.03.2006. Düsseldorf, Köln: German Medical Science; 2006. DocPO459

The electronic version of this article is the complete one and can be found online at:

Published: March 20, 2006

© 2006 Mautner et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Malignant peripheral nerve sheath tumors (MPNST) are aggressive malignancies with extremely poor prognosis. Although rare in the general population (incidence of 0.001), MPNST arise in 8-13% of patients with NF1 being the main cause for mortality in NF1 patients. Therapeutic options beside surgery are unsatisfying. Recently we showed that the expression of PDGFRA was present in 21 out of 28 (MPNST) patients. Two patients carried somatic PDGFRA mutations in exon 4 and 10 leading to amino acid exchanges. Several polymorphisms were detected in PDGFRA. PDGFRA were amplified in tumors from 6 NF1 patients and KIT in tumors from 4 NF1 patients. Both genes were amplified in an MPNST cell culture. This is why it was suggested that MPNST patients may benefit from imantinib treatment. An open label phase II study will determine the safety and efficacy of imantinib in patients with unresectable or metastatic MPNST without chemotherapy or followingprogression after chemotherapy. The primary objective is the response. The secondary objective is the time to progression and overall survival. The treatment consists of the oral drug imantinib, applied once daily with a starting dose of 400 mg. After 6 weeks, a first evaluation of the tumor progress is necessary. This is performed by MRI as well as FDG-PET. In case of progress further treatment will be decision of the responsible physician.If tumor volume is stable during therapy with imantinib accompanied by a good clinical condition, the dose will be increased to 800 mg imantinib. In case of tumor regression, surgical options can should be proven. If surgery is not possible, treatment will be continued until progression. So far 2 NF1 patients with MPNST and NF1 were treated with imantinib with different outcome. In an 18 year old patient the medication did not show any effect during a follow up of 2 months with tumor progression, whereas stable disease was achieved in a 22 year old man during treatment of three months.