The role of stereotactic radiosurgery in the treatment of malignant skull base tumors.
OBJECTIVE
To determine the efficacy and toxicity of stereotactic radiosurgery in the treatment of malignant skull base tumors.


METHODS
Thirty-two patients with 35 newly diagnosed or recurrent malignant skull base tumors < or = 33.5 cm3 were treated using the Leksell Gamma unit. Tumor histologies included: adenoid cystic carcinoma [12], basal cell carcinoma [1], chondrosarcoma [1], chordoma [8], nasopharyngeal carcinoma [3], osteogenic sarcoma [2], and squamous cell carcinoma [8].


RESULTS
After a median follow-up of 2.3 years, 83% +/- 15% (+/-95% confidence interval) of patients experienced a symptomatic response to treatment. Local control at the skull base was 95 +/- 9% at 2 years and 78 +/- 23% at 3 years. Local-regional control above the clavicles was 75 +/- 15% at 1 year and 51 +/- 20% at 2 years. Overall and cause specific survival were identical, 82 +/- 13% at 1 year, 76 +/- 14% at 2 years, and 72 +/- 16% at 3 years. One patient developed a radiation-induced optic neuropathy 12 months after radiosurgery.


CONCLUSIONS
Stereotactic radiosurgery using the Leksell Gamma Unit can provide durable tumor control and symptomatic relief with acceptable toxicity in the majority of patients with malignant tumors 4 cm or less in size involving the skull base. Further evaluation of more patients with longer follow-up is warranted.
Miller
R C
RC
Division of Radiation Oncology, Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA.
Foote
R L
RL
Coffey
R J
RJ
Gorman
D A
DA
Earle
J D
JD
Schomberg
P J
PJ
Kline
R W
RW
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000601:surgery*; D016634:Radiosurgery; D019292:Skull Base Neoplasms / Q000601:surgery*; D014786:Vision Disorders / Q000209:etiology