ESTRO 36 Abstract Book

S327 ESTRO 36 _______________________________________________________________________________________________

PO-0626 Quality of life: result from a randomized trial that compared WBRT with radiosurgery of tumor cavity L. Kepka 1 , D. Tyc-Szczepaniak 2 , K. Osowiecka 1 , A. Sprawka 3 , B. Trabska-Kluch 4 , B. Czeremszyńska 1 , M. Olszyna-Serementa 2 1 Independent Public Health Care Facility of the Ministry of the Interior and Warmian & Mazurian Oncology Centre, Radiotherapy, Olsztyn, Poland 2 Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Radiotherapy, Warsaw, Poland 3 Centre of Oncological Diagnostics and Therapy, Radiotherapy, Tomaszów Mazowiecki, Poland 4 Medical University of Lodz, Radiotherapy, Lodz, Poland Purpose or Objective Recently published randomized trial (NCT01535209) demonstrated no difference in neurocognitive function between stereotactic radiotherapy of the tumor bed (SRT- TB) (15Gy/1 fraction or 25Gy/5 fractions) and whole brain radiotherapy (WBRT) (30Gy/10fractions) in patients with resected single brain metastasis. Patients treated with SRT-TB had lower overall survival compared with WBRT arm due to the excess of neurological deaths. We compared study arms for health-related quality of life (HR-QoL). Material and Methods A self-assessed questionnaire was used to assess the QoL (EORTC QLQ-C30 with -BN20 module) at baseline prior to RT, 2 months after RT and every 3 months thereafter. QoL results were presented as mean scores and compared between arms and time points using the Wilcoxon rank sum test. Results Of 59 randomized patients, 37 (64%) were eligible for QoL analysis; 15 received SRT-TB and 22 had WBRT. There was no difference in global health status QoL/main function scales/symptoms (except for drowsiness which was worse in WBRT arm 2 months after RT [p=0.048]) between arms. Global health status QoL decreased 2 and 5 months after RT, but significantly only for SRT-TB (p=0.025). Physical function decreased significantly 5 months after SRT-TB (p=0.008). Future uncertainty worsened after RT, but significantly only for SRT-TB arm at 2 months (p=0.036). Patients treated with WBRT had significant worsening of appetite, drowsiness, and hair loss after treatment. Visual disorders improved after RT, significantly for WBRT; constipation worsened after RT, significantly for SRT-TB arm (figures: 1 and 2).

increased antigen load allowing for stronger immune reaction toward mutant clones. Larger series and translational research is needed to elucidate this finding. PO-0625 Accelerated-hypofractionated IMRT plus Temozolomide in Glioblastoma:a phase I dose- escalation study M. Ferro 1 , G. Macchia 1 , F. Deodato 1 , S. Cilla 2 , A.C. Melone 1 , P. Pagnano 1 , M. Ferro 1 , M. Boccardi 1 , A. Ianiro 2 , A. Arcelli 3,4 , S. Cammelli 3 , A. Farioli 5 , G.P. Frezza 4 , M. Ciuffreda 6 , G. Sallustio 6 , S. Chiesa 7 , M. Balducci 7 , V. Valentini 7 , A.G. Morganti 3 1 Fondazione di Ricerca e Cura “Giovanni Paolo II”, Radiotherapy Unit, Campobasso, Italy 2 Fondazione di Ricerca e Cura “Giovanni Paolo II”, Medical Physics Unit, Campobasso, Italy 3 University of Bologna, Radiation Oncology Center- Department of Experimental- Diagnostic and Specialty Medicine - DIMES, Bologna, Italy 4 Ospedale Bellaria, Radiotherapy Department, Bologna, Italy 5 University of Bologna, Department of Medical and Surgical Sciences - DIMEC, Bologna, Italy 6 Fondazione di Ricerca e Cura “Giovanni Paolo II”, Radiology Unit, Campobasso, Italy 7 Policlinico Universitario “A. Gemelli”- Università Cattolica del Sacro Cuore, Department of Radiotherapy, Rome, Italy Purpose or Objective We performed a dose-escalation trial to determine the maximum tolerated dose (MTD) of Volumetric Modulated Arc Therapy (VMAT) with standard concurrent and sequential-dose temozolomide (TMZ) in patients with resected glioblastoma multiforme. Material and Methods Histological proven glioblastoma patients underwent VMAT dose escalation. VMAT was delivered over 5 weeks with the simultaneous integrated boost (SIB) technique to the two planning target volumes (PTVs) defined by adding 5-mm margin to the respective clinical target volumes (CTVs). CTV1 was defined by adding a 10-mm isotropic margin to the tumor bed plus any MR enhancing residual lesion; CTV2 was defined as the CTV1 plus 20-mm isotropic margin. Radiation dose was escalated to the PTV1 with the SIB-VMAT strategy. Two dose levels were planned: Level 1 (PTV2: 45/1.8Gy; PTV1: 72.5/2.9Gy) and Level 2 (PTV2: 45/1.8Gy; PTV1: 75/3Gy). All treatments were delivered in 25 fractions. Patients were treated in cohorts of between three and six per group using a Phase I study design. The recommended dose was exceeded if two of the six patients in a cohort experienced dose-limiting toxicity within 3 months from treatment. Concurrent and sequential TMZ chemotherapy was administered according to Stupp’s protocol. Results Seventeen consecutive glioblastoma patients [male/female: 7/10; median age: 58 years) were treated. Six patients were treated at first dose level, with one of them experiencing a dose-limiting toxicity (DLT) (grade 3 neurological toxicity with seizures requiring hospitalization). Being the MTD not exceeded, the PTV1 dose was escalated to the highest planned dose level (75/3 Gy) and 11 patients were treated without any further DLT. After a median follow-up time of 7 months, no grade >2 late neurological toxicity was recorded. Conclusion The SIB-VMAT technique was found to be feasible and safe at the recommended doses of 45Gy to PTV2 and 75Gy (biological effective dose – BED - of 150 Gy, alpha/beta 3) to PTV1 in the postoperative treatment of patients with glioblastoma.