Background: Most patients with oesophageal cancer (OC) present with incurable disease; 80% of new cases, and deaths, occur in low and middle income nations. Median survival for advanced disease is 3-5 months, a majority requiring intervention for dysphagia. Insertion of self expanding metal stents is the commonest way of palliating, but dysphagia may recur within three months owing to tumour progression. Evidence reviews have called for trials of combination treatment for OC dysphagia. The ROCS study (funding - UK NIHR programme) examined effectiveness of palliative radiotherapy, following stent, in maintaining swallow. It also examined impact on quality of life, bleeding events, and survival. Methods: A multicentre RCT with follow up monthly for a year. Patients referred for stent insertion as primary management of dysphagia related to incurable OC were recruited in secondary care, with all planned follow up at home. Patients were randomised 1:1 to stent insertion alone or stent insertion plus palliative radiotherapy at a dose of 20Gy in five fractions or 30Gy in ten fractions. Primary outcome was difference in proportions of participants with recurrent dysphagia at 12 weeks, defined as deterioration of 11 points or more in the dysphagia scale of the EORTC QLQ-OG25 questionnaire. Secondary outcomes included quality of life, bleeding risk, survival. Results: 220 patients were randomised Dec 2013-Aug 2018 at 23 UK sites. Addition of radiotherapy did not reduce the proportion of primary events at 12 weeks: 49% in control arm vs 45% in the intervention, adjusted OR 0.82 (95%CI 0.40-1.68; p = 0.587) and it was less cost effective. Sensitivity analyses did not alter the results. Dysphagia deterioration-free survival was similar in both arms: adjusted HR 0.92 (95%CI 0.68-1.26; p = 0.618). Median survival was 19.7 weeks in control arm and 18.9 weeks in the intervention. Those in the radiotherapy arm had significantly fewer bleeding events (18.6% compared to 10.3%), giving a number needed to treat of 12. Conclusions: Palliative external beam radiotherapy is widely accessible to patients with advanced cancer. ROCS is the largest trial assessing its role in combination with stenting for OC dysphagia, and is the first to prospectively assess impact on bleeding risk. It demonstrates no reduction in risk of dysphagia recurrence at 12 weeks, nor impact on survival. Reductions in bleeding events should be considered in the context of patient described trade offs of fatigue and burdens of attending hospital. Clinical trial information: NCT01915693.