Radiosurgery for cranial base chordomas and chondrosarcomas.
OBJECTIVE
To evaluate the efficacy and toxicity of radiosurgery in the treatment of cranial base chordoma and chondrosarcoma.


METHODS
We reviewed 29 patients with cranial base chordoma (n = 25) or chondrosarcoma (n = 4) who underwent stereotactic radiosurgery between September 1990 and December 2002. The median patient age was 45 years (range, 10-81 yr). Nineteen patients also had radiation therapy before or in conjunction with radiosurgery (median dose, 50.4 Gy). The median tumor volume was 14.4 cm3 (range, 0.6-65.1 cm3). The median tumor margin dose was 15 Gy (range, 10-20 Gy); the median maximum radiation dose was 30 Gy (range, 20-40 Gy). Median clinical and imaging follow-up periods were 4.8 and 4.5 years, respectively.


RESULTS
Seven chordoma patients (28%) had tumor progression (in-field, n = 3; out-of-field, n = 4), whereas 18 had stable disease or tumor shrinkage. No patient with a chondroid chordoma had tumor enlargement. The actuarial tumor control rates were 89 and 32% at 2 and 5 years, respectively. All 4 patients with chondrosarcoma had tumor control. Clinically, 7 patients (24%) had improvement of pretreatment symptoms, 16 (55%) remained stable, and 6 (21%) worsened. Three patients with tumor progression died. Ten patients (34%) had radiation-related complications. Complications included cranial nerve deficits (n = 6), radiation necrosis (n = 5), and pituitary dysfunction (n = 3). Patients having radiosurgery alone had no toxicity.


CONCLUSIONS
Cranial base chordomas and chondrosarcomas remain a formidable management challenge. Radiosurgery as an adjunct to surgical resection provides in-field tumor control for some patients, but radiation-related complications are relatively high, especially when radiosurgery is combined with fractionated radiation therapy.
Krishnan
Sunil
S
Division of Radiation Oncology, Department of Oncology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
Foote
Robert L
RL
Brown
Paul D
PD
Pollock
Bruce E
BE
Link
Michael J
MJ
Garces
Yolanda I
YI
D002813:Chondrosarcoma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D002817:Chordoma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery; D012189:Retrospective Studies; D019292:Skull Base Neoplasms / Q000601:surgery*; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome