Radiation Therapy Dose Escalation for Glioblastoma Multiforme in the Era of Temozolomide

Journal Article · Sat Nov 15 04:00:00 EST 2014 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2014.07.014· OSTI ID:22420477

Badiyan, Shahed N.; Markovina, Stephanie; Simpson, Joseph R.; Robinson, Clifford G.; DeWees, Todd ^[1]; Tran, David D.; Linette, Gerry ^[2]; Jalalizadeh, Rohan ^[1]; Dacey, Ralph; Rich, Keith M.; Chicoine, Michael R.; Dowling, Joshua L.; Leuthardt, Eric C.; Zipfel, Gregory J.; Kim, Albert H. ^[3]; Huang, Jiayi ^[1]

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1. Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri (United States)
2. Division of Medical Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri (United States)
3. Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri (United States)

Purpose: To review clinical outcomes of moderate dose escalation using high-dose radiation therapy (HDRT) in the setting of concurrent temozolomide (TMZ) in patients with newly diagnosed glioblastoma multiforme (GBM), compared with standard-dose radiation therapy (SDRT). Methods and Materials: Adult patients aged <70 years with biopsy-proven GBM were treated with SDRT (60 Gy at 2 Gy per fraction) or with HDRT (>60 Gy) and TMZ from 2000 to 2012. Biological equivalent dose at 2-Gy fractions was calculated for the HDRT assuming an α/β ratio of 5.6 for GBM. Results: Eighty-one patients received SDRT, and 128 patients received HDRT with a median (range) biological equivalent dose at 2-Gy fractions of 64 Gy (61-76 Gy). Overall median follow-up time was 1.10 years, and for living patients it was 2.97 years. Actuarial 5-year overall survival (OS) and progression-free survival (PFS) rates for patients that received HDRT versus SDRT were 12.4% versus 13.2% (P=.71), and 5.6% versus 4.1% (P=.54), respectively. Age (P=.001) and gross total/near-total resection (GTR/NTR) (P=.001) were significantly associated with PFS on multivariate analysis. Younger age (P<.0001), GTR/NTR (P<.0001), and Karnofsky performance status ≥80 (P=.001) were associated with improved OS. On subset analyses, HDRT failed to improve PFS or OS for those aged <50 years or those who had GTR/NTR. Conclusion: Moderate radiation therapy dose escalation above 60 Gy with concurrent TMZ does not seem to improve clinical outcomes for patients with GBM.

• OSTI ID: 22420477
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 4 Vol. 90; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BIOPSY
COMPARATIVE EVALUATIONS
DIAGNOSIS
DOSE EQUIVALENTS
GLIOMAS
MULTIVARIATE ANALYSIS
PATIENTS
RADIATION DOSES
RADIOTHERAPY
REVIEWS