title: Proton beam therapy: the context, future direction and challenges become clearer.
authors.affiliation: NHS England National Clinical Lead Proton Beam Therapy, UK; St James's Institute of Oncology, Leeds Teaching Hospitals NHS Trust, Leeds, UK. Electronic address: Adrian.crellin@leedsth.nhs.uk.
authors.forename: A M
authors.initials: AM
authors.lastname: Crellin
authors.affiliation: University of Cambridge Department of Oncology, Cambridge Biomedical Campus, Addenbrooke's Hospital, Cambridge, UK; NCRI Clinical and Translational Radiotherapy Research Working Group (CTRad), UK.
authors.forename: N G
authors.initials: NG
authors.lastname: Burnet
mesh_terms: D006801:Humans; D009313:National Health Programs; D009369:Neoplasms / Q000532:radiotherapy*; D061766:Proton Therapy / Q000191:economics / Q000379:methods* / Q000639:trends; D011879:Radiotherapy Dosage; D006113:United Kingdom