ESTRO 2024 - Abstract Book

S917

Clinical - CNS

ESTRO 2024

2501

Digital Poster

Update of a real-world study on regorafenib in GBM relapse: does treatment volume impact on toxicity?

Ciro Mazzarella 1 , Antonella Martino 1 , Serena Bracci 1 , Francesco Beghella Bartoli 1 , Giorgio D'Alessandris 2 , Simona Gaudino 3 , Silvia Mariani 1 , Elisabetta Lepre 1 , Roberta Bertolini 1 , Nicola Dinapoli 1 , Loredana Dinapoli 1 , Fabio Marazzi 1 , Alessandro Olivi 2 , Luca Tagliaferri 1 , Maria Antonietta Gambacorta 1 , Silvia Chiesa 1 1 Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC Radioterapia, Dipartimento Diagnostica per Immagini, Radioterapia Oncologica ed Ematologia, Rome, Italy. 2 Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC Neurochirugia, Dipartimento di neuroscienze, Organi di Senso e Torace, Rome, Italy. 3 Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC Neuroradiologia, Dipartimento Diagnostica per Immagini, Radioterapia Oncologica ed Ematologia, Rome, Italy

Purpose/Objective:

The treatment of recurrent glioblastoma (GBM), despite multidisciplinary management in first-line approach, remains a challenge. In the phase 2 REGOMA trial, regorafenib improved overall survival (OS) at first progression after chemo-radiotherapy. Some real-world evidences showed similar impact on OS but a higher rate of adverse events than in REGOMA trial. The aim of this observational study was to assess the safety and the tolerability of regorafenib in our real-life clinical practice and the potential impact of radiotherapy treatment volume on toxicity outcomes, particularly for neurological toxicity.

Material/Methods:

Consecutive patients with GBM treated with regorafenib at recurrence were included in a retrospective observational evaluation. Data collected were: patient demographics, diagnosis, performance status (PS), number of previous lines of treatment, number of regorafenib cycles, toxicities, treatment discontinuation, survival data, radiotherapy parameters and Clinical Target Volume (CTV) in cc. OS and Progression-Free Survival (PFS), defined as the time from first administration of regorafenib to tumour progression, were estimated using the Kaplan-Meier method

Results:

Sixty-one patients were included (25 males and 36 females). Median age was 55 years (range 24-76). All patients had a PS between 0-2. Fifty-eight (98.2%) patients received regorafenib as second-line treatment; 3 (1.8%) patients as third-line due to a recurrence occurred before January 2018. Surgery at the time of recurrence was done in 15 (9,1%) patients. MGMT status was methylated for 29 (47.5%), unmethylated for 23 (37.7%), while in 9 (14.7%) patients the data was not available. The median number of cycles received was 3 (range 1-14). All the patients received radiotherapy and median CTV was 181 cc. The most common adverse events grade 1-2 were fatigue (70%), rash and desquamation (14.1%), hand-foot skin reaction (9.2%), hypertension (15%), hyperbilirubinemia (3%), hypertransaminasaemia (18%) and seizure (8%). The most common grade 3 or 4 were oedema (14%), rash (4.8%),