Canadian guidelines for the management of small renal masses (SRM).

The incidence of SRMs has increased with the widespread use of imaging and this, in turn, has increased the incidence of RCC. Mortality rates are not increasing, despite the rising incidence and increased treatment.6,7 The established standard treatment for localized RCC has been radical nephrectomy.8 More recently, partial nephrectomy has become the recommended treatment.9,10 Results of surgical therapy are excellent, with over 90% disease-specific survival for stage T1a.11 Probe ablation and active surveillance are alternative management strategies with similar efficacy.12 SRMs are frequent in the elderly and infirm, in whom the risk of treatment must be weighed against life expectancy and malignant potential of the tumour.5 About 20% to 25% of SRMs are benign.13 Even if SRMs are malignant, most of them grow slowly. Most studies have reported that the rates of malignant pathology, higher grade, higher pathological stage, growth and the risk of metastasis increase with tumour size.14 Small RCCs may be associated with metastatic disease at diagnosis in up to 8% of cases, so initial staging of all SRM patients is essential.15 Based on current data, initial active surveillance (AS) with delayed treatment for local progression appears to be a relatively safe initial management strategy.