Radiotherapy Added to Standard Care Delays Lung Cancer Progression
In the SARON trial, adding radiotherapy to standard treatment kept an advanced form of lung cancer from progressing 56 percent longer, results presented at ESMO 2026 show.
Patients with an advanced form of lung cancer lived 56 percent longer without their disease progressing when radiotherapy was added to standard whole-body treatment, according to initial results of the SARON trial presented at the 2026 European Society for Medical Oncology (ESMO) Congress.
The trial is funded by Cancer Research UK and sponsored by University College London. Dr Fiona McDonald, a consultant thoracic clinical oncologist at The Royal Marsden NHS Foundation Trust and chief investigator, presented the findings. The study covers oligometastatic non-small cell lung cancer, where the disease has spread to a small number of secondary sites by the time of diagnosis. For these patients, standard care is systemic treatment: chemotherapy, immunotherapy or both.
How the trial worked
The phase II randomised controlled trial enrolled 140 patients at 19 UK centres, each with between one and five metastases in no more than three organs. Half received standard systemic treatment alone. The other half also had local consolidation radiotherapy, high-dose treatment aimed at controlling the cancer, delivered to every known site of disease: the primary lung tumour, nearby lymph nodes and secondary tumours elsewhere. Depending on a tumour's size and location, this could involve stereotactic ablative radiotherapy (SBRT), a highly accurate method for small, well-defined tumours.
After a median follow-up of 37.4 months, the cancer did not progress for an average of 13.9 months in the radiotherapy group, against 8.9 months with systemic treatment alone. Within 12 months, the original disease sites had progressed in 13 percent of patients who had radiotherapy, compared with 39.5 percent of those on standard treatment alone.
Median overall survival was 31 months in the radiotherapy arm and 28 months in the control arm. The trial radiotherapy was well tolerated, with no significant reduction in patients' quality of life.
Until now, randomised evidence on adding radiotherapy to systemic treatment for these patients has been limited. McDonald said SARON provides important data, "demonstrating a significant improvement in progression-free survival without compromising quality of life".
One participant, 69-year-old Julie Moran from Buckinghamshire, was diagnosed with oligometastatic lung cancer after a CT scan in September 2020 and was referred to The Royal Marsden, where she joined the trial. She had immunotherapy followed by radiotherapy. "The treatment worked remarkably well and, six years later, I'm still stable," she said. She returned to work and, now retired, spends more time with her grandchildren and great-grandchild.
The CyberKnife at The Royal Marsden, a machine that delivers SBRT to some SARON patients, was funded by The Royal Marsden Cancer Charity.