ESTRO 2021 Abstract Book

S183

ESTRO 2021

Conclusion In NSCLC patients at high risk of irradical resection according to the Rasing score, CRT results in inferior survival compared to surgery. Therefore, a choice of CRT instead of surgery cannot solely be based on the Rasing risk score. Since patients who end up receiving a R1-2 resection do have detrimental outcomes compared to primary CRT, the treatment decision should be based on additional information not covered by the Rasing score, such as imaging features and the surgeon’s confidence in achieving a R0 resection. PH-0274 NLR & ALC as prognostic markers in patients treated with curative intent radiotherapy for NSCLC C. Hiley 1,2 , A. Punjabi 3 , E. Barrett 3 , A. Cheng 4 , A. Mulla 3 , G. Walls 5 , D. Johnston 6 , J. McAleese 6 , K. Moore 7 , J. Hicks 7 , K. Blyth 7 , M. Denholm 8 , L. Magee 8 , D. Gilligan 8 , S. Silverman 2 , M. Qureshi 9 , H. Clinch 10 , M. Hatton 9 , L. Philips 11 , S. Brown 12 , M. O'Brien 11 , F. Macdonald 11 , C. Faivre-Finn 13,14 , M. Evison 3 1 University College London, CRUK Lung Cancer Centre of Excellence, London, United Kingdom; 2 University College London Hospital, Oncology, London, United Kingdom; 3 Manchester University NHS Foundation Trust, Wythenshawe Hospital, Manchester, United Kingdom; 4 Manchester University NHS Foundation Trust, , Wythenshawe Hospital, London, United Kingdom; 5 Queen’s University Belfast, Oncology, Belfast, United Kingdom; 6 Cancer Centre Belfast City Hospital, Oncology, Belfast, United Kingdom; 7 NHS Greater Glasgow & Clyde, Oncology, Glasgow, United Kingdom; 8 Cambridge University Hospitals NHS Trust, Oncology, Cambridge, United Kingdom; 9 Weston Park Hospital, Oncology, Sheffield, United Kingdom; 10 The University of Sheffield Medical School, Oncology, Sheffield, United Kingdom; 11 Royal Marsden Hospital, Oncology, London, United Kingdom; 12 The University of Manchester, Oncology, Manchester, United Kingdom; 13 The University of Manchester, CRUK Lung Cancer Centre of Excellence, Manchester, United Kingdom; 14 The Christie NHS Foundation Trust, Clinical Oncology, Manchester, United Kingdom Purpose or Objective Neutrophil-Lymphocyte ratio (NLR) and absolute lymphocyte count (ALC) have been proposed as prognostic markers in non-small cell lung cancer (NSCLC). The objective of this study was to examine the association of NLR/ALC pre and post curative-intent radiotherapy (RT) for NSCLC on disease recurrence and overall survival. Materials and Methods A retrospective study of consecutive patients who underwent curative-intent RT for NSCLC across 9 sites in the UK from 01/10/2014 to 01/10/2016. A multivariate analysis was performed to assess the ability of pre- treatment NLR/ALC, post-treatment NLR/ALC and change in NLR/ALC, adjusted for co-founding factors using the Cox proportional hazards model, to predict disease recurrence and overall survival (OS) within 2 years of treatment.