Should Radical Nephrectomy Be Standard Of Care For Renal Cortical Tumours 4cm Or Less? Raised Incidence Of Chronic Renal Disease After Radical Nephrectomy

Since the studies of Robson, radical nephrectomy has remained the gold standard for treatment of renal cortical tumours. More recently, partial nephrectomy, even in the setting of a normal contralateral kidney, has demonstrated oncologic equipoise with radical nephrectomy for resection of renal tumours that in anatomically favourable sites and are 7 cm or less.

The obvious benefit of partial nephrectomy over radical nephrectomy is the salvage of functional nephron mass. Recent studies have suggested that despite numerous studies that have demonstrated the efficacy of partial nephrectomy (both open and laparoscopic), nephron sparing surgical approaches remain a rarity in the practice patterns of urologists, even in the setting of small renal masses. Here Huang and colleagues demonstrate that there is a significantly higher incidence of renal insufficiency after radical nephrectomy when compared to partial nephrectomy, providing further compelling evidence that nephron sparing approaches, when feasible, should be pursued as a surgical plan.In this study, 662 patients underwent radical or partial nephrectomy for renal cortical tumours less than 4 cm who had a normal serum creatinine and a normal contralateral renal unit based on imaging. The authors used the abbreviated Modification of Diet in Renal Disease (MDRD) study equation to estimate glomerular filtration rate (GFR) and defined chronic renal insufficiency as a GFR < 60 ml/min per 1.73m2. Of note, 171 patients (26%) had pre-existing chronic renal disease based on pre-operative GFR estimation. Following surgery, the 3 year probability of freedom from a GFR < 60 was 80% for partial nephrectomy versus 35% for radical nephrectomy (p< 0.0001). The 3 year probability of freedom from a GFR < 45 was 95% partial nephrectomy versus 64% for radical nephrectomy (p<0.0001). In their multivariate analysis, radical nephrectomy remained an independent risk factor that predicted chronic renal disease after surgery (p<0.0001).This study demonstrates that clinically significant renal disease exists, even in the setting of a normal appearing contralateral kidney and a normal serum creatinine. When appropriate, nephron sparing approaches should be considered a new standard of care for small renal masses to avoid the sequelae of chronic renal insufficiency.(Source: Lancet Oncology : December 2006.)