Table 1.

NTCP and TCP model parameters in calculating NTCP and TCP values for all investigated treatment plans and in risk-adaptive optimization as its input parameters instead of physical dose.

Structures	D50 [Gy]	Gamma(γ50) or m & n	References
Organs-at-risk (OAR)
Bladder	80.0	m = 0.11 & n = 0.5	Kutcher and Burman [29]
Unspecific Pelvic Normal tissue	55.0	m = 0.13 & n = 0.15	Kutcher and Burman [29]
Rectum (1)	81.9	m = 0.19 & n = 0.23	Rancati et al [30]
Rectum (2)*	75.7	m = 0.14 & n = 0.24	Rancati et al [30]
Rectum (3)*	55.9	m = 0.16 & n = 1.03	Tucker et al [31]
Tumor Subvolume classification
Intermediate risk (M)	72.8	γ50 = 2	Levegrün et al [25]
Very high risk (H+)	82.3	γ50 = 2
Selected D50 and γ50 Combination
H+-M22	Nodule : Very high risk (H+), γ50 = 2 rPTV :Intermediate risk (M), γ50 = 2

Abbreviations: D₅₀ = the dose yielding a 50% dose-response for a specific end point to either normal tissue complications or tumor control, γ₅₀ = the normalized dose-response gradient, m = the parameter is related to the slope of the dose-response curve $\left(m=\stackrel{1}{}/\underset{\sqrt{2\pi }{\gamma }_{50}}{}\right)$, n = the volume effect (cf. no volume effect has been assumed for individual normal tissue voxels when optimizing risk-adaptive optimization [5]),

^*= They were added to minimize NTCP model parameter dependency when calculating NTCP values (no use in an optimization process for risk-adaptive optimization).