Ultrasound-guided Core Biopsy of Small Renal Masses: Diagnostic Rate and Limitations

US-guided core biopsy is a feasible and safe procedure for histologic diagnosis of a SRM. However, nondiagnostic rates may increase when a cystic mass is biopsied, a mass is located in an upper pole mass, a mass is 2 cm or less, and three cores or fewer are sampled.