Table 2.

Normal tissue complication probabilities for dose-optimized plans and reductions achieved by biological effectiveness guided optimization

OAR, Endpoint	Group	Mean (range) NTCP(DRBE)/%	Mean (range) ΔNTCP(DRBE) to DOSEopt/percentage points
		DOSEopt	TEopt	LETopt	DDopt	DRBEopt
Brainstem, necrosis
	All	6.6 (0.7–18.0)	3.0* (0.5–8.6)	2.6* (0.4–8.0)	2.5* (0.6–6.0)	2.2* (0.2–7.0)
	Dpres ≤ 54	2.6 (0.7–4.8)	1.5 (0.5–2.3)	1.4 (0.5–2.3)	1.4 (0.6–2.1)	1.0 (0.2–2.2)
	Dpres > 54	10.6 (1.0–18.0)	4.5 (0.5–8.6)	3.8 (0.4–8.0)	3.6 (0.7–6.0)	3.5 (0.5–7.0)
Chiasm, blindness
	All	16.8 (11.0–22.0)	8.8* (4.5–16.9)	7.7* (2.0–16.8)	9.5* (4.5–16.2)	10.7* (1.0–18.4)
	Dpres ≤ 54	16.3 (11.0–21.0)	6.1 (4.6–16.9)	6.1 (2.0–16.8)	5.7 (4.5–16.2)	7.1 (2.0–16.2)
	Dpres > 54	17.2 (12.0–22.0)	7.8 (4.5–10.7)	5.7 (2.3–8.0)	8.6 (4.9–10.9)	11.9 (1.0–18.4)
Opticus R, blindness
	All	9.7 (0.2–20.0)	5.3* (0.2–9.0)	5.3* (0.2–10.4)	4.9* (0.2–10.0)	3.7* (0.1–16.5)
	Dpres ≤ 54	5.4 (0.2–9.3)	2.0 (0.2–3.0)	2.8 (0.2–6.1)	2.8 (0.2–5.4)	1.7 (0.1–3.0)
	Dpres > 54	13.0 (5.4–20.0)	6.2 (3.0–9.0)	5.6 (2.9–10.4)	6.4 (3.6–10.0)	9.2 (2.8–16.5)
Opticus L, blindness
	All	11.2 (1.0–30.0)	5.2* (0.5–15.0)	4.8* (0.5–15.0)	4.9* (0.6–13.0)	6.0* (1.0–17.3)
	Dpres ≤ 54	13.5 (6.2–30.0)	6.5 (2.8–15.0)	6.6 (3.6–15.0)	6.4 (2.8–13.0)	5.7 (2.8–13.0)
	Dpres > 54	9.3 (1.0–27.0)	4.2 (0.5–12.0)	3.3 (0.5–8.0)	3.8 (0.6–9.0)	6.2 (1.0–17.3)

^*p < 0.05 tested for group ‘all patients’, D_pres prescription dose, NTCP normal tissue complication probability, D_RBE variable RBE-weighted dose, R right, L left, DOSEopt dose-only optimization, TEopt track-end optimization, LETopt dose-averaged linear energy transfer (LET_d) optimization with dose threshold, DDopt dirty dose optimization, DRBEopt variable RBE-weighted dose optimization