title: Linear accelerator-based stereotactic radiosurgery for brainstem metastases: the Dana-Farber/Brigham and Women's Cancer Center experience.
abstract: To review the safety and efficacy of linear accelerator-based stereotactic radiosurgery (SRS) for brainstem metastases. We reviewed all patients with brain metastases treated with SRS at DF/BWCC from 2001 to 2009 to identify patients who had SRS to a single brainstem metastasis. Overall survival and freedom-from-local failure rates were calculated from the date of SRS using the Kaplan-Meier method. Prognostic factors were evaluated using the log-rank test and Cox proportional hazards model. A total of 24 consecutive patients with brainstem metastases had SRS. At the time of SRS, 21/24 had metastatic lesions elsewhere within the brain. 23/24 had undergone prior WBRT. Primary diagnoses included eight NSCLC, eight breast cancer, three melanoma, three renal cell carcinoma and two others. Median dose was 13 Gy (range, 8-16). One patient had fractionated SRS 5 Gy ×5. Median target volume was 0.2 cc (range, 0.02-2.39). The median age was 57 years (range, 42-92). Follow-up information was available in 22/24 cases. At the time of analysis, 18/22 patients (82%) had died. The median overall survival time was 5.3 months (range, 0.8-21.1 months). The only prognostic factor that trended toward statistical significance for overall survival was the absence of synchronous brain metastasis at the time of SRS; 1-year overall survival was 31% with versus 67% without synchronous brain metastasis (log rank P = 0.11). Non-significant factors included primary tumor histology and status of extracranial disease (progressing vs. stable/absent). Local failure occurred in 4/22 cases (18%). Actuarial freedom from local failure for all cases was 78.6% at 1 year. RTOG grade 3 toxicities were recorded in two patients (ataxia, confusion). Linac-based SRS for small volume brainstem metastases using a median dose of 13 Gy is associated with acceptable local control and low morbidity.
authors.affiliation: Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center, Boston, MA 02115, USA. pkelly@lroc.harvard.edu
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Kelly
authors.forename: Yijie Brittany
authors.initials: YB
authors.lastname: Lin
authors.forename: Alvin Y C
authors.initials: AY
authors.lastname: Yu
authors.forename: Alexander E
authors.initials: AE
authors.lastname: Ropper
authors.forename: Paul L
authors.initials: PL
authors.lastname: Nguyen
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Marcus
authors.forename: Fred L
authors.initials: FL
authors.lastname: Hacker
authors.forename: Stephanie E
authors.initials: SE
authors.lastname: Weiss
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020295:Brain Stem Neoplasms / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods*