This study was conducted to determine prognostic factors for tumor response
and patient survival after stereotactic radiosurgery (SRS) for brain metas
tasis. Eighty-four patients with brain metastasis underwent SRS at a single
institution. After fixation of the head with a stereotactic frame, compute
d tomography treatment planning was performed. The metastatic lesion was tr
eated with multiple arcs to a median dose of 19 Gy. Forty-seven patients (5
6%) had a solitary brain lesion. Fifty-nine patients (70%) had evidence of
extracranial disease at the time of SRS. The median survival duration from
SRS was 7 months. Sixty-three percent of the patients had an objective radi
ographic response to SRS, which in turn was associated with superior centra
l nervous system control. Age, collimator size, number of arcs, tumor locat
ion, and histology did not influence objective response rates. Patients who
had a solitary lesion or who received treatment within 2 weeks after diagn
osis were more likely to have an objective response than were those who did
not (P < 0.05). Progressive brain disease accounted for 37% of the deaths.
Nineteen patients (23%) had an in-field relapse. Four severe complications
were attributed to SRS. This study confirms the role of SRS as an acceptab
le treatment option for patients with solitary or limited brain metastases,
(C) 2000 Wiley-Liss, Inc.