Joseph JP, Potretzke TA, Packiam V, et al. - Researchers explored the safety as well as the diagnostic yield of percutaneous core-needle biopsy (PCNB) for upper tract urothelial carcinoma (UTUC) in a sample of 42 patients who had PCNB prior to radical nephroureterectomy (RNU) for UTUC. The median tumor size was 3.8 cm and the origin of all lesions occurred from the pelvicalyceal system. In 52% (n = 22) and in 48% (n = 20), the use of CT-guidance and ultrasound-guidance, respectively, was done. Histologic concordance was shown by 95% of PCNBs vs RNU pathology. In 69% (n = 29) of PCNBs, histologic grade was granted, with a 90% (n = 26) concordance with surgical pathology. They found no cases of radiographic tract seeding at a median follow up of 28.2 months following biopsy. Findings are suggestive of the safety of PCNB as a diagnostic modality with high histologic yield and grade concordance in patients undergoing RNU for UTUC.