EAU 2017: Should partial nephrectomy be considered an imperative indication in stage II chronic kidney disease?

London, England (UroToday.com) At present, partial nephrectomy (PN) is strongly indicated in patients with stage III or worse (GFR < 60) chronic kidney disease (CKD). However, PN remains a relative indication for patients with stage II CKD (GFR 60-89). The authors compared renal functional and survival outcomes for patients with baseline stage II CKD who underwent PN or radical nephrectomy (RN).

The study design was a multicenter retrospective analysis of 1,213 patients with a mean follow-up of 70.0 months. Renal function was nearly evenly split between CKD IIa (GFR 75-89.9, 50.2%) and CKD IIb (GFR 60-74.9, 49.8%). The primary outcome was change in GFR for patients who underwent PN versus RN. Secondary outcomes were occurrence of CKD IIIb (GFR < 45) and overall survival.

The mean change in GFR for patients with CKD IIa was -10.1 for PN compared to -23.7 for RN (p < 0.001). For patients with CKD IIb, the change in GFR was -3.5 for PN and -15.7 for RN (p < 0.001). On multivariable analysis, CKD 2b (OR 2.68, 95% CI 1.26-5.69) and performance of RN (OR 3.68, 95% CI 1.72-7.87) were significantly associated with occurrence of CKD IIIb. Five-year freedom from CKD IIIb stratified by baseline GFR and procedure type was 94.3% for CKD IIa/PN, 91.5% for CKD IIa/RN, 87.6% for CKD IIb/PN, and 82.0% for CKD IIb/RN (p < 0.001). Performance of RN (OR 3.71, 95% CI 1.50-9.41) and occurrence of CKD IIIb were independently associated with all-cause mortality. Five-year overall survival stratified by baseline kidney function and procedure type was 97.6% for CKD IIa/PN, 95.2% for CKD IIa/RN, 93.2% for CKD IIb/PN, and 92.4% for CKD IIb/RN (p = 0.043). The main limitations to this study are selection biases associated with retrospective study design.

The authors concluded that patients with preoperative CKD II who undergo RN are at increased risk of developing de novo CKD stage IIIb compared to those who undergo PN. Specifically, patients with CKD IIb represent a high-risk subgroup for renal functional decline and reduced overall survival compared to CKD IIa. When oncologically safe, PN should be prioritized in this at-risk population.

Speaker(s): I.H. Derweesh, San Diego, US

Written By: Benjamin T. Ristau, MD, SUO Fellow, Fox Chase Cancer Center, Philadelphia, PA.

at the #EAU17 - March 24-28, 2017- London, England