Background: Accurate nodal staging in intermediate- to high-risk prostate cancer is crucial for treatment decisions. While extended pelvic lymph node dissection (ePLND) is the standard, it is invasive and has a low diagnostic yield. A 2019 analysis suggested that non-invasive imaging techniques, such as PSMA-PET/CT and ferumoxtran-enhanced MRI (m-MRI), are cost-effective but less effective than ePLND, based on limited evidence. Recent Phase 3 trials have provided new data, prompting a reevaluation. Methods: We adapted a Markov model to simulate lifetime outcomes for men with intermediate- to high-risk prostate cancer from the perspective of a German insurer, with costs updated to 2025 euros. Diagnostic accuracy data were obtained from recent multicenter trials. Costs and QALYs were calculated using a 3% discount rate. Sensitivity analyses examined uncertainties. A practical, interactive tool is provided for clinical decision-making and research purposes, capable of incorporating various types of input data. Results: Both imaging options were dominant over ePLND (€35,155; 18.61 QALYs). PSMA-PET/CT was €6,609 cheaper and gained 0.31 QALYs; m-MRI was €8,759 cheaper and gained 0,49 QALYs. m-MRI was superior, saving €2,150 and gaining 0.18 QALYs over PSMA-PET/CT. The probabilistic analysis showed that m-MRI was optimal over 95% of the time at an €80,000/QALY threshold; the probability of PSMA-PET/CT being optimal was less than 5%. Conclusions: An imaging-first approach outperforms routine ePLND, with m-MRI as a cost-effective option. PSMA-PET/CT's low sensitivity limits its usefulness, though it’s still cheaper than ePLND. These results support the inclusion of m-MRI in guidelines for initial staging.