Cooper S, et al. - In this retrospective study involving 195 patients, researchers compared diagnostic yield and complication rate in needle biopsy (NB) of renal hilar and cortical masses. For this investigation, they recorded operator years of experience, biopsy technique (coaxial or successive), needle gauge (22-gauge fine-needle aspiration, 18-gauge core-needle, or both), number of passes, postprocedural complication and histopathologic diagnoses. According to findings, the percutaneous biopsy of renal hilar masses is technically feasible with a diagnostic yield similar to that of cortical masses, but more frequently with postprocedural bleeding than cortical masses. No association was found between diagnosis and operator years of experience, biopsy technique, needle gauge, or the number of passes.