Cost-effectiveness of [¹¹C]Choline PET/CT as first-line imaging in primary hyperparathyroidism

Purpose We performed a cost-utility analysis, using prospectively gathered trial data, comparing two imaging strategies for localizing parathyroid adenomas in primary hyperparathyroidism (pHPT) to determine the most cost-effective approach. Additionally, we provide customizable open-source R-script enabling other centres to identify their optimal imaging strategy based on local diagnostic accuracy and cost data. Methods An evaluation of the diagnostic accuracy was performed for five imaging modalities: first-line cervical ultrasound (cUS) and [ 99m Tc]Tc-methoxy isobutyl isonitrile-single-photon-emission-computed- tomography/computed-tomography (MIBI SPECT/CT), and second-line [¹¹C]choline positron-emitting-tomography/CT (PET/CT), [¹¹C]methionine PET/CT, and 4 dimensional (4D)-CT. A decision-tree-model, constructed in R-studio, compared two diagnostic pathways: (1) The comparator pathway: a stepwise approach starting with cUS and MIBI SPECT/CT escalating to one of three second-line imaging modalities if needed, and (2) use of only one second-line imaging. Costs and quality-adjusted life years (QALYs) were evaluated across pathways, and cost-utility ratios (€/QALY) were calculated for a centre specific perspective with a 24-year time horizon based on life expectancy. In addition, to test the joint parameter uncertainty of the model, a probabilistic Monte-Carlo analysis was performed. One- and two-way sensitivity analyses were conducted to assess model robustness. Results [¹¹C]choline PET/CT had a total costs of €10,394 and a QALY gain of 16.66. In contrast, the current standard, cUS + MIBI SPECT/CT with, when necessary, second-line imaging, costs €10,907 and yields 16.63 QALYs. The incremental cost-utility ratio (ICUR) for [¹¹C]choline PET/CT was -€18,846/QALY, indicating dominance with lower cost and greater effectiveness. Sensitivity analyses showed that cost-effectiveness was most sensitive to variations in costs of [¹¹C]choline PET/CT. Conclusion This centre-specific model supports first-line [¹¹C]choline PET/CT as a cost-effective first-line strategy for localization of parathyroid adenomas, depending on [¹¹C]choline PET/CT costs. Additionally, the provided cost-utility model, enables other centres to determine their optimal imaging strategy.