Vienna, Austria

ESTRO 2023

Session Item

May 13
16:45 - 17:45
Plenary Hall
Palliation - Oligometastases
Mateusz Spałek, Poland;
Vincent Khoo, United Kingdom
Proffered Papers
17:25 - 17:35
Early toxicity of SBRT for oligometastatic cancer patients in the EORTC/ESTRO OligoCare cohort


Early toxicity of SBRT for oligometastatic cancer patients in the EORTC/ESTRO OligoCare cohort

Filippo Alongi1, Umberto Ricardi2, Marta Scorsetti3, Lorenzo Livi4, Panagiotis Balermpas5, Yolande Lievens6, Pètra Braam7, Barbara Alicja Jereczek-Fossa8, Karin Stellamans9, Ivica Ratosa10, Joachim Widder11, Heike Peulen12, Piet Dirix13, Luc Verbeke14, Sara Ramella15, Hossein Hemmatazad16, Kaouthar Khanfir17, Xavier Geets,18, Paul Jeene19, Thomas Zilli20, Beatrice Fournier21, Catherine Fortpied22, Felix Boakye Oppong23, Piet Ost24, Matthias Guckenberger25

1 IRCCS Sacro Cuore Don Calabria Hospital & University of Brescia, Advanced Radiation Oncology, Negrar (Verona), Italy; 2Università degli Studi di Torino, Torino, Italy, Radiation Oncology, Torino, Italy; 3Humanitas University, Department of Biomedical Sciences, Pieve Emanuele (Milan), Italy; 4Azienda Ospedaliero-Universitaria Careggi , Radiation Oncology, Florence, Italy; 5University Hospital Zürich, University of Zürich , Radiation Oncology, Zurich, Switzerland; 6Radiation Oncology Department, Ghent University Hospital and Ghent University, Radiation Oncology, Ghent, Belgium; 7Radboud University Medical Center Nijmegen, Radiation Oncology, Nijmengen, The Netherlands; 8European Institute of Oncology and University of Milan, Oncology and Hemato-oncology department, Milan, Italy; 9Campus Kennedylaan, AZ Groeninge Kortrijk , Kortrijk , Belgium; 10Istitute Of Oncology, Radiation Oncology, Ljubljana, Slovenia; 11Universitaetsklinikum Wien, Radiation Oncology, Wien, Austria; 12 Catharina Ziekenhuis, Radiation Oncology, Eindhoven, The Netherlands; 13 Iridium Network, Radiation Oncology,, Wilrijk , Belgium; 14 Onze-Lieve-Vrouw Ziekenhuis, Radiation Oncology, Aalst, Belgium; 15Policlinico Universitario Campus Bio-Medico- Oncology Center, Policlinico , Radiation Oncology, Roma, Italy; 16Bern University Hospital (Inselspital), Radiation Oncology, Bern, Switzerland; 17Hopital de Sion, Hopital du Valais , Radiation Oncology, Sion, Switzerland; 18 Cliniques Universitaires Saint-Luc, -, Brussels, Belgium; 19Radiotherapiegroep, -, Deventer, The Netherlands; 20Hôpitaux universitaires de Genève - HUG - site de Cluse-Roseraie, , Radiation Oncology, Geneve, Switzerland; 21European Organisation for Research and Treatment of Cancer (EORTC) , Headquarters, Brussels, Belgium; 22 European Organisation for Research and Treatment of Cancer (EORTC) , Headquarters, Brussels, Belgium; 23 (European Organisation for Research and Treatment of Cancer (EORTC) , Headquarters, Brussels, Belgium; 24Iridium Network, Radiation Oncology, Wilrijk, Belgium; 25University Hospital Zürich, University of Zürich, Radiation Oncology, Zürich, Switzerland

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Purpose or Objective

Several randomized phase II trials have reported improved outcome if local ablative therapies were added to standard-of-care treatment of oligometastatic cancer patients with very low rates of toxicity. In this analysis, based on the first patients included in the ongoing ESTRO/EORTC E²-RADIatE OligoCare cohort, we report on the early toxicity for patients treated with SBRT for oligometastatic cancer.

Material and Methods

The analysis is based on a snapshot of the database on October 10th 2022 including only the first 1100 enrolled patients. A total of n=1002 were included in this analysis after exclusion of non-eligible patients or patients with incomplete data. The current update reports the patient characteristics and adverse events observed within 6 months of the start of SBRT, using the CTCAE v5 scale. Only events of grade 3 or higher related to radiotherapy are reported.


Patients were treated with SBRT at 32 centers across 9 European countries for oligometastatic breast (n=163), colorectal (n=183), non-small cell lung (n=198) or prostate cancer (n=458). The majority of patients had a good performance status (WHO 0-1: 82.4%). In 97% of cases, less than 4 metastases were irradiated, with most patients receiving radiotherapy for a single metastasis (67.2%). The most common organ sites irradiated were non-vertebral bones (22.9%), lung (20.8%), non-regional lymph nodes (18.3%) and spine lesions (15.8%). The median clinical target volume was 3.7cc (Q1-Q3: 1.2-12.8cc). The median number of fractions was 5 (range 1-11) with a median dose of 9.4 Gy per fraction (Q1-Q3: 7.5-12.2Gy). The median dose per fraction was highest for metastases from colorectal primaries at 13.1Gy per fraction, followed by NSCLC (10.2Gy), breast (8.6Gy) and prostate cancer (8.5Gy). The median BED, using an α/β of 10, delivered was 73 Gy (Q1-Q3 (59.7-104.4). SBRT was delivered in combination with systemic therapy in 38.3% of cases.
There were only 0.5% of patients with grade 3 or higher adverse events reported. In total 4 cases of grade 3 toxicity were reported (pain: 1, empyema: 1, pneumonia: 1, decreased appetite: 1) and 1 grade 5 toxicity (pneumonitis). In total, 6 patients (0.6%) were diagnosed with a new primary malignancy and 27 patients died (2.7%) within the first 6 months of follow-up.


Very few grade 3 or higher toxicity are being observed in the OligoCare cohort, with the vast majority of patients being alive at 6 months follow-up. Up-to-date data will be presented at the ESTRO congress.