ESOU18: Alternative Approaches for Characterization of Renal Tumors - Conventional and Optical Renal Mass Biopsy

Amsterdam, The Netherlands ( The European Association of Urology (EAU) guidelines recommend performing a renal biopsy only before ablative therapy and systemic therapy without previous pathology. The guidelines also state to consider a biopsy in select patients who are considered for active surveillance (AS). Unfortunately, CT and MRI scans are sensitive in detecting renal masses, but lack specificity in distinguishing renal masses. Renal mass biopsy (RMB) is highly accurate but with a high non-diagnostic rate as well. Importantly, 20-40% of renal masses are benign.

Optical Coherence Tomography (OCT) is an advanced imaging modality based on the back scattering of near-infra red light. It has high axial resolution with a penetration depth of 2-3 mm. It is the optical equivalence of ultrasound.

Dr. Reijke reported on a study attempting to determine the accuracy and diagnostic yield of OCT and RMB for the differentiation of renal masses. All patients included in the study were adults (>18) with enhancing, solid renal mass on cross sectional imaging, and candidates for active treatment. The study intervention included a percutaneous OCT performed during RMB.

Overall, 95 patients were enrolled. The diagnostic yield of the RMB was 79% with very high sensitivity, specificity, positive predictive values (PPV) and negative predictive value (NPV). The OCT demonstrated sensitivity, specificity, PPV, and NPV of 92%, 67%, 95%, and 55%, respectively, to differentiate oncocytoma from renal cell carcinoma (RCC) and a benign mass from RCC.

The authors concluded that compared to RMB, OCT has a higher diagnostic yield, and OCT successfully distinguishes benign renal masses from RCCs, and Oncocytomas from RCC. OCT could serve as an add-on to RMB in order to reduce the relatively high non-diagnostic rate of RMB.

Speaker: Theo M. de Reijke MD, Uro-oncology European Organization for Research and Treatment of Cancer – Genito Urinary group (EORTC-GU), Academic Medical Center, Urology Amsterdam, The Netherlands

Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at The 15th Meeting of the EAU Section of Oncological Urology ESOU18 - January 26-28, 2018 - Amsterdam, The Netherlands