Risk of symptomatic brain tumor recurrence and neurologic deficit after radiosurgery alone in patients with newly diagnosed brain metastases: results and implications.
OBJECTIVE
A single-institution experience using primary stereotactic radiosurgery (SRS) alone in the management of newly diagnosed brain metastases was analyzed to identify the risk of symptomatic brain tumor recurrence (BTR) and neurologic deficit associated with such a treatment strategy.


METHODS
Thirty-six patients were treated for newly diagnosed single/multiple brain metastases using SRS alone followed by planned observation. SRS minimum tumor dose ranged from 8 to 25 Gy (median: 20 Gy). Factors evaluated in analysis of treatment outcome included number of metastases, site of metastasis, primary tumor site, histology, extent of intracranial and extracranial disease, and interval to diagnosis of brain metastasis.


RESULTS
Median and 1-year survival for the entire group was 9 months and 36%, respectively. BTR anywhere in the brain occurred in 47% (17/36) of patients. Forty-seven percent of BTR (8/17) recurred at the site of original metastasis; 35% (6/17) recurred at both original [corrected] and distant sites in the brain, and 18% (3/17) recurred at distant only [corrected] brain sites. Seventy-one percent (12/17) of the patients were symptomatic at the time of recurrence, and 59% (10/17) had an associated neurologic deficit. Multivariate analysis found that only the extent of disease was a predictor of BTR. Patients who had disease limited to the brain only had a BTR rate of 80% (8/10) vs. 35% (9/26) who had disease involving the brain, primary site, and/or other extracranial metastatic sites (p = 0.03).


CONCLUSIONS
Use of primary SRS alone in this setting is associated with an increasingly significant risk of BTR with increasing survival time. In addition, the majority of such recurrences are symptomatic and associated with a neurologic deficit, a finding not analyzed in recently reported experiences withholding whole brain radiation therapy as part of the primary treatment of brain metastasis.
Regine
William F
WF
Department of Radiation Medicine, University of Kentucky, Lexington, KY 40536-0084, USA. wilregi@pop.uky.edu
Huhn
Jennifer L
JL
Patchell
Roy A
RA
St  Clair
William H
WH
Strottmann
James
J
Meigooni
Ali
A
Sanders
Michael
M
Young
A Byron
AB
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001932:Brain Neoplasms / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009422:Nervous System Diseases / Q000209:etiology; D016634:Radiosurgery / Q000379:methods*; D011879:Radiotherapy Dosage; D016879:Salvage Therapy; D016019:Survival Analysis; D016896:Treatment Outcome