S847
Clinical - Lung
ESTRO 2026
Digital Poster Highlight 4578
SUNSET.
Twelve-month radiographic disease control by Green criteria independently predicts survival after hypofractionated radiotherapy for NSCLC hebatalla abdelaal 1 , Ala Elwasila 1 , Hitesh Mistry 2 , Nashwah Ismail 1 , Corinne Faivre-Finn 1,2 1 cllinical oncology, the Christie NHS foundation trust, Manchester, United Kingdom. 2 division of cancer sciences, the university of Manchester, Manchester, United Kingdom Purpose/Objective: For over two decades, RECIST has been the standard for assessing radiological tumour response. However, post-radiotherapy CT interpretation in lung cancer is often confounded by fibrosis and volume changes. The Green criteria provide an alternative, defining disease control as complete disappearance of disease or stable residual abnormalities on CT at 3 months that remain unchanged at 6 and 12 months after radiotherapy1. This study evaluated whether 12- month disease control (DC12m) by adapted Green criteria independently predicts overall survival after curative-intent hypofractionated radiotherapy. Material/Methods: A retrospective study was conducted at a single academic UK centre, Inclusion criteria were: NSCLC histology, stage 1-3, treatment with curative-intent hypofractioned radiotherapy alone (55 Gy in 20 fractions), availability ≥ 2 post-radiotherapy CT scans. DC12m was defined as stable/decreased abnormality on ≥ 2 CT scans post-radiotherapy (DC) versus progression or death within 12 months (NoDC); patients lost-to-follow-up were coded as missing. OS was measured from start of radiotherapy. Intercurrent events (death or initiation of new therapy within 12 months) were addressed using an estimand framework accounting for intercurrent events and missing imaging. OS was compared between groups using Kaplan–Meier and log-rank tests. Multivariable Cox models adjusted for gross tumour volume (GTV, modelled with restricted cubic splines), clinical stage, smoking, underlying lung disease, and performance status. Results: A total of 446 lung cancer patients treated between January 2019-December 2021, 293 met inclusion criteria for OS analysis.104 patients had 2 CT scans, and 189 patients had 3 CT scans post-RT. Patients and tumour characteristics are summarised in table 1. At 12 months, 123 patients (41.9 %) achieved DC12m, and 144 (49.1 %) had NoDC. Two-year unadjusted OS was 89% for DC vs 32% for NoDC (log-rank χ² = 98.3, p< 10 ⁻ ¹⁶ ). In multivariable Cox analysis adjusting for known prognostic factors, DC12m remained a strong independent predictor of OS (adjusted HR = 3.97, 95%
Conclusion: These findings suggest that SABR lung studies, including SOURCE, buck the trend of non-age-inclusive clinical studies by enrolling patients reflective of the real-world population. Accrual to date on the SOURCE study demonstrates that older adults are willing to consent to participate in research when these opportunities are accessible. The diversity of participants across age and functional status should increase relevance of the SOURCE study findings, once published, to real world clinical practice. References: Sedrak MS, et al. Cancer and Aging Research Group (CARG). Older adult participation in cancer clinical trials: A systematic review of barriers and interventions. CA Cancer J Clin. 2021 Jan;71(1):78- 92. Ayodele O, et al. Comparing attitudes of younger and older patients towards cancer clinical trials. J Geriatr Oncol. 2016 May;7(3):162-8Giuliani, M., et al. Stereotactice Radiation for Ultra-Central Non-Small Cell Lung Cancer: A Safety and Efficacy Trial (SUNSET) Clin Lung Cancer. 2018 19(4):e529-e532 Levy A, Adebahr S, Hurkmans C, et al. Stereotactic Body Radiotherapy for Centrally Located Inoperable Early- Stage NSCLC: EORTC 22113-08113 LungTech Phase II Trial Results. J Thorac Oncol. 2024 Sep;19(9):1297- 1309. Keywords: Geriatric, Inclusion, SABR.
Made with FlippingBook - Share PDF online