Chemoradiation is the standard of care for the treatment of anal canal cancer, with surgery reserved for salvage. For tumours with uninvolved inguinal nodes, it is standard to irradiate the inguinal nodes prophylactically, resulting in large field sizes, which contribute to acute and late toxicity. The aim of this single-centre retrospective study was to determine if, in selected cases, prophylactic inguinal nodal irradiation could be avoided.