Endoscopic ultrasound-guided fine-needle aspiration for the diagnosis of kidney lesions: A review

Abstract
Traditionally, treatment of renal lesions is indicated based only on imaging features. Although controversy exists about tissue sampling from small renal masses, renal biopsy is indicated in some cases. In this review, we discuss the rationale for endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and summarize the recent advances in this field, providing recommendations for the practicing clinician. The use of EUS-FNA appears to be a safe and feasible means of confirming or excluding malignancy. EUS allows assessment and biopsy of masses or lesions within both kidneys and related complications are rare. The main advantages of EUS-FNA are that it can be done as an outpatient procedure, with good results, minimal morbidity and a short hospital stay. Nevertheless, EUS-FNA of renal masses should be indicated only in selected cases, in which there is potential to decrease unnecessary treatment of small renal masses and to best select tumors for active surveillance and minimally invasive ablative therapies. Additionally, some renal lesions may be ineligible for EUS-guided biopsy because of anatomical limitations. EUS-FNA renal biopsy will probably be best applied to central anterior renal masses, while tumors on the posterior aspect of the kidney, percutaneous access will probably be superior.