In an article by Patel et al published in BJUI (2012) the authors studied 234 patients with suspected renal cancer less than 4cms in size. 71 were treated by surveillance, 41 by radical nephrectomy and 90 by partial nephrectomy. After a median follow up of 34 months over 53% of masses managed by surveillance had not increased in size and only 1 (with multiple tumours) had spread. 20% went on to ablative therapy. Cancer specific survival was 99%, 93% and 97% with overall survival of 83%, 80% and 90% for surveillance, radical and partial nephrectomy groups respectively. The authors conclude that active surveillance of renal masses <4cms is as safe as surgery in the short term.