ESTRO 2025 - Abstract Book

S1557

Clinical – Mixed sites & palliation

ESTRO 2025

3389

Digital Poster Analysis of local control and pain relief of rib metastases treated with Stereotactic Body Radiotherapy Chiara Mattioli 1 , Gabriele Simontacchi 1 , Mauro Loi 1 , Pietro Garlatti 1 , Michele Aquilano 2 , Daniela Greto 1 , Emanuela Olmetto 1 , Vieri Scotti 1 , Monica Mangoni 1 , Viola Salvestrini 1 , Pierluigi Bonomo 1 , Alessandra Galardi 1 , Silvia Calusi 3 , Cinzia Talamonti 3 , Ilaria Morelli 1 , Andrea Romei 1 , Carolina Orsatti 1 , Ilaria Bonaparte 1 , Luca Burchini 1 , Cecilia Petruccioli 1 , Luisa Caprara 1 , Doruntina Cela 1 , Lorenzo Livi 1 1 Radiation Oncology, Azienda Ospedaliero Universitaria Careggi, Università di Firenze, Firenze, Italy. 2 CyberKnife Center, Istituto Fiorentino di Cura e Assistenza (IFCA), Firenze, Italy. 3 Medical Physics Unit, AOU Careggi, Firenze, Italy Purpose/Objective: Recent reports highlighted the efficacy of Stereotactic Body Radiotherapy (SBRT) in treating vertebral metastases 1 , leading to an increased use of SBRT also in non-spinal bone metastases 2-5 . However, the treatment of rib metastases (RM) has been traditionally limited due to concerns about the risk of iatrogenic fractures, which could negatively impact pain management. This study aims to assess pain control and local failure rates in RM patients treated with SBRT. Material/Methods: We retrospectively analyzed data from RM patients treated with SBRT between January 2010 and December 2023. Inclusion criteria required a minimum dose of 16, 21 and 25 Gy in 1, 3 and 5 fractions, respectively. Clinical and treatment-related data were collected. Pain control (PC) was defined as the absence of pain or pain reduction sufficient to decrease painkillers use without subsequent relapse. Local control (LC) was calculated between SBRT treatment and the appearance of local progression on follow-up imaging. We performed both univariable analysis using the log-rank test and multivariable analysis using the Cox model to identify predictors of PC and LC. Results: We included data from 87 patients with 103 RM (Table 1). The median age was 69.5 years (range 35 – 89). The most common primary tumours were prostate cancer (44%, n=45) and non-small cell lung cancer (17%, n=18). Prior to SBRT, 37 (36%) lesions were painful, with 12 (12%) requiring daily opioid use. SBRT was delivered using Volumetric Arc Radiotherapy (57%, n=59) or robotic-arm Linac (43%, n=44).