Partial vs. radical nephrectomy and the risk of all-cause mortality, cardiovascular, and nephrological outcomes.

Abstract

The study's objective was to examine the effects of renal-preservation surgery on long-term mortality, cardiovascular outcomes, and renal-related outcomes. We performed a retrospective cohort study of all partial (n=575) and radical nephrectomies (n=882) for tumors ≤7 cm in diameter between 2002 and 2010 across three academic centers in Ontario, Canada. We linked records from provincial databases to assess patient characteristics and outcomes (median seven years' followup using retrospective data). A weighted propensity score was used to reduce confounding. The primary outcome was all-cause mortality. Secondary outcomes included hospitalization with major cardiovascular events, non-cancer related mortality, kidney cancer-related mortality, and dialysis. Mean one-year postoperative estimated glomerular filtration rate (eGFR) was 71 mL/min/1.73 m2 in the partial group and 52 mL/min/1.73 m2 in the radical group. Partial nephrectomy was associated with a lower risk of all-cause mortality in the first five years after surgery (hazard ratio [HR] 0.42, 95% confidence interval [CI] 0.27-0.66), which did not extend beyond five years (HR 1.01, 95% CI 0.68-1.49). Kidney cancer-related mortality was lower in the partial compared to the radical group for the first four years after surgery (HR 0.16, 95% CI 0.04-0.72). There were no significant differences between the groups for cardiovascular outcomes or non-cancer related deaths. Overall survival and cancer-specific survival was reduced in radical nephrectomy patients. However, despite reduced renal function in the radical nephrectomy group, non-cancer-related death, cardiovascular events, and dialysis were not significantly different between groups. Long-term benefits of partial nephrectomy may be less than previously believed.