Cost-effectiveness of the implementation of [68Ga]Ga-PSMA-11 PET/CT at initial prostate cancer staging

Insights into Imaging

Table 2 Yearly input parameters of the lifetime state transition model

Parameter	Value	Distribution (SE)	Source
Lifetime state transition model probabilities
Probability BCR in the NEOD-N1 (pBCR)	0.45 (Gompertz; Rate 0.66, shape -0.38)	Normal	Mandel et al. [21]
Percentage with BCR to salvage	0.63	Beta (0.063)	De Bruycker et al. [22]
N1-NEOD to salvage	pBCR * Percentage with BCR to salvage
N1-NEOD to palliative	pBCR * (1-Percentage with BCR to salvage)
Salvage to palliative	0.31	Beta (0.031)	Decaestecker et al. [23]
Cancer mortality (palliative)	0.032	Beta (0.0032)	Tumati et al. [24]
Cancer mortality (false palliative)	0.032	Beta (0.0032)	Assumption: equals Cancer Mortality
All-Cause mortality	Standard mortality rates age 69 and higher	Fixed	CBS [25]
[⁶⁸Ga]Ga-PSMA-11 PET/CT probabilities
pN0 to palliative (FP)	0	Fixed	PSMA PET/CT indicates multiple LNMs in N0 patients
pN1_lim to palliative (FP)	0.027	Beta (0.027)	PSMA PET/CT indicates multiple LNMs in N1_lim
Costs (€)
NEOD-N0 and N1	108	Gamma (€11)	De Rooij et al. [26]
(False) palliative	4,613¹	Gamma (€1,153)	Schwenk et al. [27] FK [28]
Salvage	8,022²	Gamma (€802)	Schwenk et al. [27]
Palliative to death (transition cost)	16,720	Gamma (€1,672)	Tien et al. [29]
Utilities (QALY)
NEOD-N0 and N1	0.81³	Beta (0.081)	Versteegh et al. [30]
Scholte et al. [10]
(False) palliative	0.67	Beta (0.067)	Stewart et al. [31]; Asymptomatic spread
Salvage	0.77	Beta (0.077)	Heijnsdijk et al. [32]; RT

All-cause mortality was derived from the Dutch public data [25] regarding mortality rates for age 69 and higher in 2019. The transition parameters BCR from NOED N1, salvage to palliative and palliative to death (Cancer mortality) were determined by fitting a Gompertz or exponential distribution on the Kaplan Meier curves, using webplotdigitizer [33]. All other transitions were derived from literature. BCR biochemical recurrence, CBS centraal bureau voor statistiek (Dutch national price index), FP false positive, LNM lymph node metastases, N0 no lymph node metastasis, N1_lim limited lymph nodes metastasis defined as less than or equal to four pelvic lymph node metastasis, NOED No evidence of disease, pBCR probability on biochemical recurrence, SE standard error, PET/CT positron emission tomography/computed tomography, PSMA prostate specific membrane antigen.
¹Cost of palliative therapy was assumed to be the costs of 66Gr Radiotherapy and 4 shots Goserilin
²Cost of salvage treatment was assumed to be the mean cost of all radiotherapy options described in Schwenk et al. [27]
³Utility was estimated using the mean utility for men aged 70–80 and a fixed correction for long-term primary treatment complications as calculated by Scholte et al. [10]