Presentation Authors: Jason Joseph*, Amir Toussi, Theodora Potretzke, Tanner Miest, Thomas Atwell, Bradley Leibovich, Matthew Tollefson, Aaron Potretzke, Rochester, MN
Introduction: Short of surgical extirpation, ureteropyeloscopy with endoscopic biopsy remains the standard for establishing a histologic diagnosis of upper tract urothelial carcinoma (UTUC). Endoscopic biopsy is safe and affords visualization; however, it is not always feasible, and its diagnostic accuracy is debated. We report our experience with percutaneous image-guided core-needle biopsy (CNB) for UTUC to better understand safety and diagnostic accuracy.
Methods: We retrospectively reviewed 444 patients undergoing radical nephroureterectomy (RNU) for UTUC at Mayo Clinic between 2009 and 2017. Forty-two patients undergoing CNB prior to RNU were identified. Clinical notes, imaging, and pathology reports were reviewed. Major complications were those grade 3 or higher according to the Common Terminology Criteria for Adverse Events.
Results: Median age at biopsy was 72.8 years (37.8-91.5). All lesions were intrarenal. Median tumor size was 3.2 cm (1.2-8.3). CT-guidance was utilized in 52.4% (n=22), ultrasound-guidance in 47.5% (n=20). Relative to RNU pathology, rate of histologic diagnosis by CNB was 95.2% (n=40). When CNB provided histologic grade (n=29, 69%), rate of concordance with surgical pathology was 86.2% (n=25). Minor and major complication rates were 14.3% (n=6) and 2.4% (n=1) respectively. At a median biopsy-to-interval imaging time of 26.2 months (1.2-76.5), no cases of CNB tract seeding were identified.
Conclusions: In our cohort undergoing RNU for UTUC, CNB was a safe and effective diagnostic tool. To our knowledge, this represents the largest reported experience with CNB for diagnosis of UTUC. Additional studies are underway to compare the diagnostic accuracy of CNB to that of endoscopic biopsy.