Salvage stereotactic radiosurgery for recurrent glioblastoma multiforme with prior radiation therapy.
BACKGROUND
Glioblastoma multiforme (GBM) carries a poor prognosis with high recurrence rates. Salvage stereotactic radiosurgery (SRS) may be an effective treatment option.


METHODS
We retrospectively reviewed 34 patients (41 lesions) treated with salvage SRS for recurrent GBM between 2004 and 2012. Initial surgical treatments were gross total resection (58%), subtotal resection (STR) (24%), and biopsy (18%). All patients were treated with prior radiation therapy. Recurrent disease was treated with salvage SRS with a median dose and fractions of 23.4 Gy (range, 12-30) and 3 (range, 1-3), respectively. Cox proportional hazards regression was conducted to establish predictive factors (P ≤ 0.05) Results: Median follow-up from salvage SRS was 10.8 months (interquartile range [IQR], 7.0-15.6). The median time from initial radiation therapy to salvage SRS was 13.7 months (IQR, 2.9-25.0). The 6- and 12-month overall survival from salvage SRS were 84.9% and 42.5%, respectively. On univariate analysis, STR was associated with inferior survival from salvage SRS (P ≤ 0.05). The 6- and 12-month local control (LC) estimates were 63.1% and 16.4%, respectively. On univariate analysis, higher biological effective dose and prior temozolomide were associated with superior LC. Concerning toxicity, there were 4 (12%) grade 2 and 1 (3%) grade 3 adverse events within this patient series. No grade 4 or grade 5 toxicities were observed.


CONCLUSIONS
Our outcomes suggest that SRS is a feasible treatment option with acceptable salvage survival rates, given the poor prognosis of this disease.
Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA.
Douglas E
DE
Holt
Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA.
Mark E
ME
Bernard
Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA.
Kimmen
K
Quan
Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA.
David A
DA
Clump
Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
Johnathan A
JA
Engh
Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA.
Steven A
SA
Burton
Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA.
Dwight E
DE
Heron
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor; D001932:Brain Neoplasms / Q000235:genetics / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D003131:Combined Modality Therapy; D005260:Female; D005909:Glioblastoma / Q000235:genetics / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009364:Neoplasm Recurrence, Local; D011401:Promoter Regions, Genetic; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods; D018714:Radiotherapy, Adjuvant / Q000009:adverse effects / Q000379:methods; D016879:Salvage Therapy; D016019:Survival Analysis; D016896:Treatment Outcome
D014408:Biomarkers, Tumor