Combination of photon and proton radiation therapy for chordomas and chondrosarcomas of the skull base: the Centre de Protonthérapie D'Orsay experience

Int J Radiat Oncol Biol Phys. 2001 Oct 1;51(2):392-8. doi: 10.1016/s0360-3016(01)01634-0.


Purpose: Prospective analysis of local tumor control, survival, and treatment complications in 44 consecutive patients treated with fractionated photon and proton radiation for a chordoma or chondrosarcoma of the skull base.

Methods and materials: Between December 1995 and December 1998, 45 patients with a median age of 55 years (14-85) were treated using a 201-MeV proton beam at the Centre de Protonthérapie d'Orsay, 34 for a chordoma and 11 for a chondrosarcoma. Irradiation combined high-energy photons and protons. Photons represented two-thirds of the total dose and protons one-third. The median total dose delivered within the gross tumor volume was 67 cobalt Gray equivalent (CGE) (range: 60-70).

Results: With a mean follow-up of 30.5 months (range: 2-56), the 3-year local control rates for chordomas and chondrosarcomas were 83.1% and 90%, respectively, and 3-year overall survival rates were 91% and 90%, respectively. Eight patients (18%) failed locally (7 within the clinical tumor volume and 1 unknown). Four patients died of tumor and 2 others of intercurrent disease. In univariate analysis, young age at time of radiotherapy influenced local control positively (p < 0.03), but not in multivariate analysis. Only 2 patients presented Grade 3 or 4 complications.

Conclusion: In skull-base chordomas and chondrosarcomas, the combination of photons with a proton boost of one-third the total dose offers an excellent chance of cure at the price of an acceptable toxicity. These results should be confirmed with a longer follow-up.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Bone Neoplasms / mortality
  • Bone Neoplasms / radiotherapy*
  • Chondrosarcoma / mortality
  • Chondrosarcoma / radiotherapy*
  • Chordoma / radiotherapy*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Photons / therapeutic use*
  • Prospective Studies
  • Proton Therapy*
  • Radiation Injuries / complications
  • Skull Base Neoplasms / mortality
  • Skull Base Neoplasms / radiotherapy*
  • Survival Analysis
  • Treatment Failure


  • Protons