OBJECTIVES: Approximately 20% of metastatic renal cell carcinoma (mRCC) patients receiving 1st line (1LT) sunitinib experience disease progression (PD) identified by RECIST at 90 days post 1LT initiation. Earlier PD identification would minimize futile1LT, facilitating a switch to potentially more effective 2nd line therapy. Current research is evaluating biomarkers that identify rapid PD (rPD). This study’s goal was to estimate the economic impact of utilizing an angiogenesis-specific imaging (AI) biomarker for early PD identification. METHODS: An economic model for mRCC patients receiving 1LT sunitinib from a UK National Health System perspective was developed with a 90 day time horizon. Comparator arm used RECIST monitoring; the intervention arm an AI biomarker. Inputs included: timing of PD assessment (day 14 for AI; day 90 for RECIST); sunitinib costs (£1,569 for 14 days; £6,950 for 90 days); other 1LT costs (£468 for 14 days; £1,861 for 90 days); and rPD rate of 20%. Outcomes included incremental length of futile 1LT and costs for AI vs. RECIST.  RESULTS: For AI sensitivity of 50%, a 38 day reduction in futile 1LT could be achieved per rPD patient by using AI vs. RECIST (AI sensitivity of 75% or 100% yielded 57 and 76 fewer days). Incremental cost savings reflecting resources that could be freed up for AI utilization across all mRCC patients was £677, £1,016 and £1,355 per patient for AI sensitivity of 50%, 75% and 100%. CONCLUSIONS: Prolonged therapy exposes non-responding patients to risks without potential clinical benefit and results in misallocated healthcare resources which could be directed elsewhere. Results of this study suggest that a diagnostic test enabling early PD identification may reduce futile 1LT and its negative clinical/economic consequences. Further research should evaluate additional benefits of early PD identification, including improved patient quality of life and/or better clinical outcomes of subsequent therapies.