Study protocol for the SARON trial: a multicentre, randomised controlled phase III trial comparing the addition of stereotactic ablative radiotherapy and radical radiotherapy with standard chemotherapy alone for oligometastatic non-small cell lung cancer

Abstract
Introduction Following growing evidence to support the
safety, local control (LC) and potential improvement in
overall survival (OS) in patients with oligometastatic nonsmall
cell lung cancer (NSCLC) that have been treated
with local ablative therapy such as stereotactic ablative
radiotherapy (SABR) and stereotactic radiosurgery (SRS),
we initiate the SARON trial to investigate the impact and
feasibility of adding SABR/SRS and radical radiotherapy
(RRT) following standard chemotherapy on OS.
Methods and analysis SARON is a large, randomised
controlled, multicentre, phase III trial for patients with
oligometastatic EGFR, ALK and ROS1 mutation negative
NSCLC (1–3 sites of synchronous metastatic disease,
one of which must be extracranial). 340 patients will be
recruited over 3 years from approximately 30 UK sites
and randomised to receive either standard platinumdoublet
chemotherapy only (control arm) or standard
chemotherapy followed by RRT/SABR to their primary
tumour and then SABR/SRS to all other metastatic sites
(investigational arm). The primary endpoint is OS; the
study is powered to detect an improvement in median
survival from 9.9 months in the control arm to 14.3
months in the investigational arm with 85% power and
two-sided 5% significance level. The secondary endpoints
are LC, progression-free survival, new distant metastasisfree
survival, toxicity and quality of life. An early feasibility
review will take place after 50 randomised patients.
Patients requiring both conventional thoracic RT to the
primary and SABR to a thoracic metastasis will be included
in a thoracic SABR safety substudy to assess toxicity
and planning issues in this subgroup of patients more
thoroughly.
Ethics and dissemination All participants are given a
SARON patient information sheet and required to give
written informed consent. Results will be submitted for
presentation at local and international conferences and
expected to be published in a peer-reviewed journal.
Trial registration number NCT02417662.
Sponsor reference UCL/13/0594.