(UroToday.com) The 2023 GU ASCO annual meeting included an oral abstract session on renal cell carcinoma (RCC), featuring a presentation by Dr. Brian Shuch discussing results from ZIRCON, a phase 3 study of 89Zr-DFO-girentuximab for PET/CT imaging of clear cell RCC. The increasing detection of renal masses presents a significant patient management challenge. Diagnostic options include cross-sectional imaging, which cannot reliably differentiate benign and malignant renal masses, and biopsy, which is invasive and subject to sampling errors. Furthermore, 20-30% of resected small renal masses are benign, and clear cell RCC is 75% of RCC and causes ~90% of deaths. These limitations highlight the unmet need for accurate noninvasive method for pre-treatment risk stratification, similar to the recent advancements in PSMA imaging in prostate cancer. Girentuximab is a monoclonal antibody that targets carbonic anhydrase IX, an enzyme highly expressed in clear cell renal carcinoma. Radiolabeled 89Zr-DFO-girentuximab (TLX250-CDx) is highly specific for carbonic anhydrase IX and can aid differentiation between clear cell RCCs and other renal lesions: