To study the effect of central tumor location on the glomerular filtration rate (GFR) after partial nephrectomy for renal cortical tumor.

We reviewed our institutional database to identify patients who had undergone partial nephrectomy from January 1995 to July 2005. Central tumors were defined as those encroaching on the collecting system or renal sinus or that did not distort the renal contour; all others were categorized as peripheral on preoperative abdominal imaging. We calculated the GFR preoperatively, during the hospital stay, and at 1 and 12 months after surgery. Linear regression models were fit to determine the association of tumor location with the changes in GFR at each period, after controlling for age, sex, operative and ischemic times, comorbidities, and blood loss.

A total of 248 central and 333 peripheral tumors were available for analysis. Patients with central tumors were younger than those with peripheral tumors (62 versus 59 years, P = 0.014) and experienced longer intraoperative renal ischemia times (40 versus 29 minutes, P <0.001) and longer operations (195 versus 179 minutes, P = 0.004). On multivariate analysis, tumor location was not significantly associated with the change in GFR at any of the intervals, after adjusting for the covariates.

The results of our study have indicated that tumor location does not appear to affect long-term renal function. Thus, partial nephrectomy should not be withheld from this subset of patients.