TABLE II.

A summary of TCP and NTCP models and parameters for CTV _prostate, bladder, and rectum used in this work. Note, conventionally TCP or NTCP values are calculated for a PTV or PRV volume. Here, TCP or NTCP are computed for the base CTV or OAR volumes during the coverage simulations, yielding distributions of the parameters.

TCP: Poisson model (Refs. 27–30)
Equation	$\begin{array}{c}\begin{array}{c}\text{TCP}=exp\left(-\frac{ln2}{N}\sum _{i}exp\left[2\frac{{\gamma }_{50}}{ln2}\left(1-\frac{{\mathrm{BED}}_i}{D_{50}}\right)\right]\right)\text{or}\hfill \\ =exp\left(-ln2\cdot exp\left[2\frac{{\gamma }_{50}}{ln2}\left(1-\frac{\text{gBEUD}}{D_{50}}\right)\right]\right)\hfill \end{array}\hfill \\ \text{where }{\mathrm{BED}}_i=D_i\cdot \left[1+\frac{D_i/n}{\left(\alpha /\beta \right)}\right]\text{ and gBEUD}={\left(\sum _i{\nu }_i\cdot {\mathrm{BED}}_i^a\right)}^{1/a}\hfill \end{array}$
Parameters	D50 (dose producing 50% tumor control), γ50 (slope parameter), a (EUD parameter), α/β (BED parameter)
CTVprostate (Ref. 31)	D50 = 67.5 Gy, γ50 = 2.2, a = 0.16, α/β = 3 Gy
NTCP: Lyman–Kutcher–Burman model (Refs. 32 and 33)
Equation	$\begin{array}{c}\text{NTCP}=\frac{1}{\sqrt{2\pi }}{\int }_{-\infty }^{t}duexp\left(-u^2/2\right)\hfill \\ \text{where }t=(\text{gBEUD}-T{D}_{50})\text{/}\left(mT{D}_{50}\right),\hfill \\ \text{gBEUD}={\left(\sum _i{\nu }_i\cdot {\mathrm{BED}}_i^a\right)}^{1/a}{\text{ and BED}}_i=D_i\cdot \left[1+\frac{D_i/n}{\left(\alpha /\beta \right)}\right]\hfill \end{array}$
Parameters	TD50 (the tolerance dose producing a 50% complication probability), m (slope parameter), a (gBEUD parameter), α/β (BED parameter)
Bladder (Refs. 34 and 35)	TD50 = 80 Gy, m = 0.11, a = 20, α/β = 5 Gy
Rectum (QUANTEC)	TD50 = 76.9 Gy, m = 0.13, a = 11.1, α/β = 5 Gy