Tumour control and normal tissue complication probability (TCP and NTCP)

Tumour control probability models take the linear-quadratic survival of clonogenic cells and ask how likely it is that none survive a given dose, producing a sigmoid dose-response; normal tissue complication probability models, from Lyman's 1985 formulation to the Lyman-Kutcher-Burman and relative seriality models, do the same for organs, incorporating how much of the organ is irradiated. The QUANTEC reviews of 2010 gathered clinical NTCP data for each organ into the constraints planners use today, and biological plan comparison and dose-painting rest on these curves. Their parameters carry wide uncertainty and immune and vascular effects are absent.