Should Small Renal Masses Be Biopsied?

Over the last few decades, the incidence of renal cell carcinomas (RCCs) has been steadily increasing. This is primarily due to an increase in detection of small renal masses (SRMs) as a result of widespread utilization of abdominal imaging. Interestingly, up to 30% of incidentally discovered SRMs (solid lesions measuring <= 4 cm) are benign, and consequently, the definitive treatment of all SRMs is associated with a considerable risk of overtreatment. To decrease the overtreatment rate, renal tumour biopsy (RTB) has been advocated as a safe alternative to identify the pretreatment histology of these SRMs. Although initially fraught with high non-diagnostic rates, more recent series from centres of experience have demonstrated that RTB is safe, reliable and accurate. The future of SRM management will combine pathological, molecular and genetic information to improve our ability to predict the behaviour of these lesions and herald riskadapted personalized treatment.