CORE: A randomised trial of COnventional care versus radioablation (stereotactic body radiotherapy) for extracranial oligometastases - Khoo, V; Ahmed, M; McDonald, F; Kirby, A; Van As, N; Hawkins, M; Syndikis, I; Franks, K; Jain, S; Tree, A; Eaton, D; Patel, R; et al. (Lung Cancer, 2017)