Chordomas of the base of the skull and upper cervical spine. One hundred patients irradiated by a 3D conformal technique combining photon and proton beams.
To define the prognostic factors for local control and overall survival among 100 consecutive patients with chordoma of the base of skull or upper cervical spine treated by fractionated irradiation combining proton and photon beams. Between December 1993 and August 2002, 100 patients (median age: 53 years [8 - 85], M/F sex ratio: 3/2) were treated by a combination of high-energy photons and protons. The proton component was delivered at the Centre de Protonthérapie d'Orsay (CPO) by a 201 MeV beam. The median total dose delivered to the tumor volume was 67 GyECo. With a median follow-up of 31 months [range: 0 - 87], 25 tumours relapsed locally. The 2- and 4-year local control rates were 86.3% (+/-3.9%) and 53.8% (+/-7.5%), respectively. According to multivariate analysis, at least 95% of the tumor volume encompassed by the 95% isodose (p = 0.048; RR: 3.4 95%CI [1.01 - 11.8]) and a minimal dose delivered into the tumor volume <56 GyECo (p = 0.042; RR: 2.3 95%CI [1.03 - 5.2]) were independent prognostic factors of local control. Ten patients died. The 2- and 5-year overall survival rates were 94.3% (+/-2.5%) and 80.5% (+/-7.2%), respectively. According to multivariate analysis, local tumor control (p = 0.005; RR: 21 95%CI [2.2 - 200]) was a prognostic factor of overall survival. For chordomas of the base of the skull and upper cervical spine treated by surgery and irradiation combining photons and protons, the quality of irradiation, reflected by homogeneity of the dose into the tumor volume, is a major factor of local control. Close attention must be paid to minimize the underdosed areas close to critical organs. The role of surgical resection remains paramount, and a trial of dose escalation would have to consider an increase in the dose to critical organs, especially as current results indicate the low toxicity of this treatment.
Noël
Georges
G
Institut Curie-CPO batiment 101, University Campus, 91898 Orsay, Cedex, France. noel@ipno.in2p3.fr
Feuvret
Loic
L
Calugaru
Valentin
V
Dhermain
Frederic
F
Mammar
Hamid
H
Haie-Méder
Christine
C
Ponvert
Dominique
D
Hasboun
Dominique
D
Ferrand
Régis
R
Nauraye
Catherine
C
Boisserie
Gilbert
G
Beaudré
Anne
A
Gaboriaud
Geneviève
G
Mazal
Alexandre
A
Habrand
Jean-Louis
JL
Mazeron
Jean-Jacques
JJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002817:Chordoma / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017785:Photons / Q000627:therapeutic use; D011379:Prognosis; D061766:Proton Therapy; D020266:Radiotherapy, Conformal / Q000379:methods*; D019292:Skull Base Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D013125:Spinal Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D015996:Survival Rate; D016896:Treatment Outcome; D011522:Protons
D011522:Protons