ESTRO 2023 - Abstract Book

S492

Sunday 14 May 2023

ESTRO 2023

Conclusion The occurrence and location of BM were similar between HA-PCI and standard PCI. In a longitudinal assessment, the percentage of patients with clinically relevant self-reported cognitive impairment was high and did not differ between HA PCI and PCI. OC-0608 Do patients with lung cancer and a genetic risk for rheumatoid arthritis have increased toxicity? A. McWilliam 1 , S. Kerns 2 , D. Marshall 3 , D. Azria 4 , J. Chang-Claude 5 , A. Choudhury 1 , S. Gutiérrez-Enríquez 6 , M. Lambrecht 7 , T. Rancati 8 , D. De Ruysscher 9 , P. Seibold 10 , C. Talbot 11 , A. Vega 12 , L. Veldeman 13 , A. Webb 14 , K. Banfill 1 , C. Faivre-Finn 1 , B. Rosenstein 15 , C. West 16 1 The University of Manchester, Division of Cancer Science, Manchester, United Kingdom; 2 Medical College of Wisconsin, Radiation Oncology, Wisconsin, USA; 3 Mount Sinai, Icahn School of Medicine , New York, USA; 4 University Montpellier, Federation Universitaire d’oncologie radiothérapie d’Occitanie Méditerranée, Montpellier, France; 5 German Cancer Research Centre, Division of Cancer Epidemiology, Heidelburg, Germany; 6 Vall d’Hebron Barcelona Hospital Campus, Hereditary Cancer Genetics Group, Barcelona, Spain; 7 Leuvens Kanker Instituut, Department of Radiotherapy-oncology, Leuven, Belgium; 8 Fondazione IRCCS Istituto Nazionale dei Tumori, Prostate Cancer Program, Milian, Italy; 9 Maastricht University Medical Center, Department of Radiation Oncology, Maastricht, The Netherlands; 10 Germant Cancer Research Centre, Division of Cancer Epidemiology, Heidelburg, Germany; 11 University of Leicester, Leicester Cancer Research Centre, Leicester, United Kingdom; 12 Grupo de Medicina Xenómica, Fundación Pública Galega de Medicina Xenómica,, Santiago de Compostela, Spain; 13 Ghent University Hospital and Ghent University, Department of Radiation Oncology, Ghent, Belgium; 14 University of Leicester, Department of Genetics and Genome Biology, Leicester, United Kingdom; 15 Department of Radiation Oncology Mount Sinai, Department of Genetics and Genomic Sciences, New York, USA; 16 The University of Manchester, Division of Cancer Sciences, Manchester, United Kingdom Purpose or Objective Overlapping genes are involved with rheumatoid arthritis (RA) and DNA repair pathways. Therefore, we hypothesised that patients with a high polygenic risk score (PRS) for RA will have an increased risk of radiotherapy (RT) toxicity. Materials and Methods Data from 530 patients with lung cancer were available from the multicentre prospective REQUITE study. Germline DNA was genotyped using Illumina OncoArray-500K BeadChips and imputed using the 1000 Genomes Project Phase 3. PRS and weighted-PRS (wPRS) were calculated for RA (101 SNPs) and analysed as continuous variables and using a >90th percentile cut-off. Univariable and multivariable linear regression models analysed relationships with: 1) acute and late standardised total averaged toxicity (STAT) scores; and 2) individual toxicity end points. Acute toxicity was defined as max reported toxicity within 90 days of RT and late toxicity defined as max reported after 90 days for cough, dyspnoea, pneumonitis, dysphagia, and oesophagitis. Multivariable analyses included the following pre-selected adjustment variables: gender, age, smoking history, chemotherapy, forced expiratory volume (FEV), lung v20, oesophagus v35, prescription dose (biologically equivalent dose), and diagnosis of chronic obstructive pulmonary disease (COPD). Results No significant association was found between PRS or wPRS with acute or late STAT. Smoking history, (p=0.03), lung v20 (p=0.008), oesophagus v35 (p=0.02) and COPD (p=0.01) showed a significant association with STAT acute. Lung v20 (p=0.03), oesophagus v35 (p=0.01) and COPD (p < 0.01) were associated with STAT late. Patients with >90th percentile for PRS showed a beta coefficient of 0.17, p=0.06 associated with worse late STAT. Patients >90th percentile for wPRS showed no association with worse STAT late. Analysing individual toxicity end points identified that patients >90th percentile for wPRS experienced significantly worse acute (coefficient 0.18, p=0.05) and late (coefficient 0.2, p = 0.03) oesophagitis. Smoking history (p=0.01), FEV (p=0.02) and COPD (p=0.05) increased risk of acute oesophagitis. FEV (p=0.02) and higher oesophagus v35 (p=0.03) were also significantly associated with worse late oesophagitis, table 2.