Stepwise multicenter introduction of intensity modulated radiation therapy for anal cancer in the United Kingdom: From consensus guidance to large-scale prospective audit, prior to future clinical trials - Gilbert, D; Drinkwater, K; O'Cathail, S; Adams, R; Glynne-Jones, R; Harrison, M; Hawkins, M; Sebag-Montefiore, D; Muirhead, R (Elsevier, 2016)