S964
Clinical - Oligometastatic cancer
ESTRO 2026
3 Stereotactic and MR-Linac Radiotherapy Department, GenesisCare UK, Leeds, United Kingdom. 4 Stereotactic and MR-Linac Radiotherapy Department, GenesisCare UK, London, United Kingdom. 5 Stereotactic and MR- Linac Radiotherapy Department, GenesisCare UK, Birmingham, United Kingdom Purpose/Objective: Stereotactic ablative body radiotherapy (SABR) has shown survival benefits in oligometastatic disease (OMD) (1-3), but its role in oligo-progressive (OPD), recurrent (ORD) and persistence (OPeD) disease, particularly in delaying systemic therapy (ST) switch, remains under evaluation. This study evaluates real- world clinical outcomes and tolerability of SABR in OMD, aiming to support a treatment paradigm that seeks to chronify metastatic cancer. Material/Methods: We retrospectively analysed a multicentre single- institution OMD cohort treated with SABR for ≤ 5 active OMD (OPD/ORD/OPeD) and performance status (ECOG) 0–2. ST was held before SABR to avoid interactions from concurrent treatment. Data on patient demographics, tumour histology, prior treatments, SABR dose/fractionation, and ST were collected. Endpoints were local control (LC), ST switch- free survival, overall survival (OS), and SABR-related toxicity (Common Terminology Criteria for Adverse Events – CTCAE- v5.0). Results: Between 2020-2025, 61 patients underwent 113 SABR courses to 168 metastases (median age: 64.5 years; 43% male). Predominant primary tumours: 24 lung (39%); 12 breast (19.7%); 11 colorectal (18%). Most (97,4%) had metastatic history before the analysed OMD-SABR (Table 1) (4).
(95%CI 56.8%–80.7%). Commonest acute side effect was fatigue (16%) and only two late grades ≥ 3 toxicity were observed. Conclusion: SABR for OMD is well-tolerated and achieves excellent LC, with potential to delay systemic therapy changes. These findings support the integration of SABR into personalized multimodal strategies. References: 1. Palma DA, et al . SABR-COMET Phase II Randomized Trial. J Clin Oncol. 2020 Sep 1;38(25):2830- 2838. 2.Phillips R, et al. ORIOLE phase 2 randomized clinical trial. JAMA Oncol 2020;6:650–9.3. Schellenberg D, et al. Randomized phase II STOP trial. Int J Radiat Oncol2023;117(2, Suppl):S58. 4.Guckenberger M, et al. Characterisation and classification of oligometastatic disease: a ESTRO and EORTC consensus recommendation. Lancet Oncol. 2020 Jan;21(1):e18- e28. Keywords: SABR/SBRT; OMD; OPD Continuation of first-line systemic therapy with radiotherapy in oligoprogressive hepatocellular carcinoma: a phase Ⅱ trial (NCT06261047) Fang Shi 1 , Haohua Wang 1 , Yongjing Yang 2 , Lijuan Ding 3 , Yi Ding 4 , Yuqin Zhang 4 , Mian Xi 5 , Yanli Qu 6 , Zhongjie Chen 7 , Yi Lu 8 , Yong qiang Yang 9 , Luying Liu 10 , Jinbo Yue 1 1 Radiation Oncology, Shandong Cancer Hospital and Institute, Jinan, China. 2 Radiation Oncology, Jilin Cancer Hospital, jilin, China. 3 Radiation Oncology, The First Hospital of Jilin University, Jilin, China. 4 Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China. 5 Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou, China. 6 Radiation Oncology, Cancer Hospital of China Medical University, Liaoning Cancer Hospital & Institute, Cancer Hospital of Dalian University of Technology, Shenyang, China. 7 Radiation Oncology, Tianjin Medical University Cancer Institute and Proffered Paper 748 Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, China. 8 Radiation Oncology, The Affiliated Lihuili Hospital of Ningbo University, Ningbo, China. 9 Radiation Oncology, The Second Affiliated Hospital of Soochow University, Soochow, China. 10 Radiation Oncology, Zhejiang cancer hospital, Hangzhou, China Purpose/Objective: Due to the limited efficacy of current second-line systemic therapy for hepatocellular carcinoma, there is a need for an effective and well-tolerated treatment strategy to avoid premature transition to SLST, particularly for patients with oligoprogressive
Median time from primary diagnosis to first OMD- SABR was 30 months (range 4-248 months). Most common SABR-regimens were 40Gy/5# (n21) and 55Gy/5# (n19). Most common SABR-target locations were bones (n36), lung (n36) and mediastinal nodes (n20). With a median follow-up of 15.2 months from OMD-SABR, 52.5% of patients were alive and 1- and 2- year LC were 86.5% and 79.2%, respectively. 1- and 2- year OS were 58% (95%CI 44-71%) and 40% (95%CI 27- 54%). The estimated 6- and 12-months ST-switch free interval were 85% (95%C I65.3% –87.2%) and 77%
Made with FlippingBook - Share PDF online