Radiation Therapy Dose Escalation for Glioblastoma Multiforme in the Era of Temozolomide
Menée sur 209 patients atteints d'un glioblastome multiforme (âge inférieur à 70 ans), cette étude évalue, par rapport à une radiothérapie à dose standard et du point de vue des taux actuariels de survie sans progression et de survie globale à 5 ans, l'efficacité d'une radiothérapie à haute dose de rayonnements en combinaison avec une chimiothérapie concomitante par témozolomide
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.
http://www.redjournal.org/article/S0360-3016(14)03493-2/abstract