gms | German Medical Science

48th Meeting of the Particle Therapy Co-Operative Group

Particle Therapy Co-Operative Group (PTCOG)

28.09. - 03.10.2009, Heidelberg

Spot-scanning proton radiation therapy for extra-cranial chordoma

Meeting Abstract

  • H. P. Rutz - Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
  • A. Staab - Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
  • B. Timmermann - Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
  • C. Ares - Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
  • A. Lomax - Center for Proton Therapy, Paul Scherrer Institute, Villigen, Schweiz
  • G. Goitein - Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
  • E. Hug - Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland

PTCOG 48. Meeting of the Particle Therapy Co-Operative Group. Heidelberg, 28.09.-03.10.2009. Düsseldorf: German Medical Science GMS Publishing House; 2009. Doc09ptcog167

DOI: 10.3205/09ptcog167, URN: urn:nbn:de:0183-09ptcog1672

Published: September 24, 2009

© 2009 Rutz et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

Text

Background: Extra-cranial chordomas (ECC) require high dose radiotherapy to achieve local control (LC). Tumor proximity to critical Organs at risk poses significant dose constraints. Proton-Radiotherapy (PT) has been employed at the Center for Proton Radiation Therapy at Paul Scherrer Institue (PSI).

Material and methods: Between 1999–2005, 40 patients with Chordoma of C-, T-, L-spine and Sacrum underwent PT. Eighteen patients had gross residual disease deemed not to be amenable to further resection (GTV, range: 13–495 ml). Twenty-one patients had undergone prior surgical stabilization (SS) of the axial skeleton. Median total dose was 72 Gy. Median follow-up time was 43 months.

Results: At 5 years, overall LC rate was 62%. One failure occurred in 19 patients without SS after 6 years, resulting in actuarial LC rate at 5 years of 100%. Twelve failures were diagnosed in 21 patients with SS, yielding a 5 year LC rate of 30% (p=0.0003). Five-year OS for the entire cohort was 80%. Differences in LC did not yet impact on OS. No high grade neurotoxicity was observed.

Conclusion: Spot scanning based PT at PSI delivered subsequently to function-preserving surgery is safe and highly effective in ECC patients without major surgical instrumentation. Results of a reduced LC rate in patients with SS prompted a detailed cause-analysis. This investigation is currently still in progress.