Figure 5

Scatterplot of V65 (%) for the rectum vs. normal tissue complication probability (NTCP, %) for LKB and logistic models ((a) and b) respectively). Patients with gastrointestinal (GI) toxicity are plotted as open red circles, the patients free from GI toxicity are represented as open black circles. For the LKB model the region with NTCP < 26% had a lower incidence of GI toxicity than the rest of the region, while for logistic model the region with a lower incidence of GI toxicity is that down NTCP value of 39%.