Poor-Prognosis Patients Affected by Glioblastoma: Retrospective Study of Hypofractionated Radiotherapy with Simultaneous Integrated Boost and Concurrent/Adjuvant Temozolomide
Fabiana Gregucci, Alessia Surgo, Ilaria Bonaparte, Letizia Laera, Maria Paola Ciliberti, Roberta Carbonara, Maria Annunziata Gentile, David Giraldi, Roberto Calbi, Morena Caliandro, Nicola Sasso, Salvatore D’Oria, Carlo Somma, Gaetano Martinelli, Giammarco Surico, Giuseppe Lombardi, Alba Fiorentino
Abstract
BACKGROUND: Glioblastoma (GBM) is a very poor-prognosis brain tumor. To date, maximal excision followed by radiochemotherapy, in 30 fractions, is the standard approach. Limited data are present in the literature about hypofractionated radiotherapy (hypo-RT) in GBM poor prognosis patients. Thus, this retrospective study was conducted to evaluate efficacy and toxicity of hypo-RT with simultaneous integrated boost (SIB) in association with temozolomide (TMZ) in this patient setting. METHODS: Poor-prognosis GBM patients underwent surgery (complete, subtotal or biopsy) followed by SIB-hypo-RT and concomitant/adjuvant TMZ. The prescription dose was 40.05 Gy (15 fractions) with a SIB of 52.5 Gy (3.5 Gy/fraction) on surgical cavity/residual/macroscopic disease. Volumetric modulated arc therapy was performed. RESULTS: From July 2019 to July 2021, 30 poor-prognosis patients affected by GBM were treated by SIB-hypo-RT; 25 were evaluated in the present analysis due to a minimum follow up of 6 months. The median age and KPS were 65 years and 60%, respectively. At the median follow-up time of 15 months (range 7-24), median and 1-year overall survival and progression-free survival were 13 months and 54%, and 8.4 months and 23%, respectively. No acute or late neurological side effects of grade ≥ 2 were reported. Grade 3-4 hematologic toxicity occurred in three cases. CONCLUSION: SIB-hypo-RT associated with TMZ in poor-prognosis patients affected by GBM is an effective and safe treatment. Prospective studies could be warranted.