Cost-Effectiveness of Incorporating [ ⁸⁹ Zr]Zr-Girentuximab PET-CT for Characterizing Small Renal Masses

The phase-3 ZIRCON trial demonstrated the diagnostic utility of [ 89 Zr]Zr-girentuximab positron emission tomography-computed tomography (TLX250-CDx) for detecting clear-cell renal cell carcinoma. We evaluated the cost-effectiveness of incorporating TLX250-CDx for small renal mass (SRM) management. We developed a decision-analytic Markov model to estimate the costs and health outcomes of competing management strategies for patients age 65 years diagnosed with an incidental SRM: empiric partial nephrectomy (reference arm), renal mass biopsy (option 1), and TLX250-CDx, followed by biopsy to confirm benign tumors (option 2). We assessed life years, quality-adjusted life years (QALYs), and direct medical costs from a US Medicare payer perspective over a lifetime horizon. We assessed incremental cost-effectiveness ratios against a $100,000/QALY willingness-to-pay threshold. Scenario and probabilistic sensitivity analyses were conducted. Option 2 achieved the lowest risk of untreated malignant tumors (0.8%) besides the reference arm (0% by default; 2.7% for option 1) and a high probability of leaving benign tumors untreated (67.7%, vs 0% for reference, 70.8% for option 1). Option 2 avoided biopsy for 57.2% of patients. Option 2 was the most cost-effective strategy. It nominally dominated option 1 and had an incremental cost-effectiveness ratio of $55,779/QALY vs the reference arm. The results were robust across sensitivity analyses. Using TLX250-CDx to characterize SRMs followed by confirmatory biopsy of negative cases helps avoid biopsy for nearly 60% of patients and treatment of over two-thirds of benign tumors, minimizes the risk of untreated malignancy (<1%), and is likely cost-effective compared with current conventional practices.