Rectal cancer

Abstract Chapter 12 discusses rectal cancer, including its clinical background, diagnosis and staging, radiotherapy planning, therapeutic assessment, and follow-up. Initial imaging is able to accurately stage and restage disease and to guide therapy (total mesorectal excision ± neoadjuvant radiotherapy or chemoradiotherapy) which has contributed to improved rectal cancer outcome. Minimally invasive surgery, sphincter preservation in low rectal cancers rather than abdominoperineal resection, and non-surgical management may be appropriate in selected patients to preserve and improve quality of life following successful treatment. In patients with an initial complete response and on active surveillance, MRI with diffusion imaging has a role in the first two years in extraluminal disease detection.