Stereotactic radiosurgery for well-circumscribed fibrillary grade II astrocytomas: an initial experience.
OBJECTIVE
To examine the role of stereotactic radiosurgery in the management of patients with progressive, well-circumscribed grade II fibrillary astrocytomas.


METHODS
During a 13-year interval, 12 patients (median age: 25 years) required multimodality management for recurrent or unresectable World Health Organization (WHO) grade II fibrillary astrocytomas. Tumors involved the brainstem (n = 4), thalamus (n = 1), cerebellum (n = 1), frontal lobe (n = 4), temporal lobe (n = 1), and parietal lobe (n = 1). Diagnosis was confirmed by stereotactic biopsy (n = 5), partial resection (n = 5), and near total resection (n = 2). Multimodality management of patients prior to radiosurgery included fractionated radiation therapy (n = 4), stereotactic cyst drainage (n = 1), and ventriculoperitoneal shunt placement (n = 2). Tumor volumes varied from 1.2 to 45.1 cm(3). The median radiosurgical dose to the tumor margin was 16 Gy.


RESULTS
After radiosurgery, serial imaging showed complete tumor resolution in 1 patient, reduced tumor volume in 4, stable tumor volume in 3, and delayed tumor progression in 4 (3 patients with increase in cyst size only). Therapy after radiosurgery included additional cytoreductive surgery (n = 1) for recurrence of a higher grade tumor, stereotactic cyst aspiration (n = 1), and stereotactic intracavitary irradiation (n = 1). All patients were alive at a median follow-up of 52 months after radiosurgery and 103 months after diagnosis. In 8 patients, follow-up lasted more than 60 months.


CONCLUSIONS
Stereotactic radiosurgery is a potential alternative or adjunctive strategy in the management of selected patients with WHO grade II fibrillary astrocytomas.
Hadjipanayis
Constantinos G
CG
Department of Neurological Surgery, University of Pittsburgh Medical Center, Pa 15213, USA.
Niranjan
Ajay
A
Tyler-Kabara
Elizabeth
E
Kondziolka
Douglas
D
Flickinger
John C
JC
Lunsford
L Dade
LD
D000293:Adolescent; D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000175:diagnosis / Q000601:surgery*; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery / Q000379:methods* / Q000706:statistics & numerical data