Radiobiological model-based approach to determine the potential of dose-escalated robust intensity-modulated proton radiotherapy in reducing gastrointestinal toxicity in the treatment of locally advanced unresectable pancreatic cancer of the head

Table 1 Normal tissue complication probability (NTCP) LKB model parameters used in biological evaluation of IMRT and ro-IMPT plans

Gastrointestinal OAR (Reference)	TD₅₀ (Gy) (range)	m (range)	n (range)	Endpoint
Stomach wall (Pan et al.) [26]	62	0.30	0.07	Gastric bleed
Stomach wall (Burman et al.) [27]	65	0.14	0.15	Ulceration/Perforation
Duodenum (Pan et al.) [26]	180	0.49	0.12	Gastric bleed
Duodenum (Holyoake et al.) [28]	299.1	0.51	0.193	Grade ≥ 3 GI toxicity
Small bowel loops (Burman et al.) [27]	55	0.16	0.15	Obstruction/Perforation
StoDuo (Pan et al.) [26]	52.5	0.35	0.21	Gastric bleed

Abbreviations: OAR organ at risk, TD₅₀(Gy) dose at which there is 50% chance of complication, m slope of dose-response curve, n dose-volume relationship

ISSN: 1748-717X