SUO 2017: Should Partial Nephrectomy Be Considered Elective In Stage 2 Chronic Kidney Disease? Propensity Score Matched Analysis Of Functional And Survival Outcomes After Radical And Partial Nephrectomy

Washington, DC (UroToday.com) Introduction: While partial nephrectomy (PN) is strongly indicated for patients with stage 3-4 chronic kidney disease [(CKD), eGFR<60 ml/min/1.73m2], higher GFRs are thought to be elective. The authors compared renal function and survival outcomes in patients with baseline stage II CKD who underwent PN or radical nephrectomy (RN).

Methods: This was a retrospective analysis of patients with baseline CKD 2 undergoing PN or RN from 1987−2015. Patients were stratified into CKD 2a (GFR 75−89) and CKD 2b (GFR 60−74.9) and analyzed according to the type of surgery. Primary outcome was change in GFR at last follow-up (eGFR). Secondary outcomes included occurrence of GFR<60, GFR<45 and overall survival.
Propensity score matching on subset of patients with all available covariates (n=1163). For a binary treatment indicator of CKD stage (CKD 2a vs. 2b), Matching was performed 1:1 between groups with a logistic regression estimation and a nearest neighbor matching algorithm. Matching was achieved for 1158 patients (579 per cohort) in this subset. Additionally, for a binary treatment indicator of surgical approach (PN vs RN), matching was achieved for 1044 patients (522 per cohort).

Results: 1213 patients analyzed (50.2% CKD 2a, 49.8% were CKD 2b, median follow-up 49 months). Overall rate of development of eGFR<60, <45, and <30 was 47.6%, 15.2%, and 3.4%, respectively. Rate of development of eGFR<60 and <45 at last follow-up was greater for CKD 2b as opposed to CKD 2a (57.8% vs. 39.0%, p<0.001; 20.5% vs. 10.4%, p<0.001;
respectively). After propensity score matching, rates of development of eGFR <60 and <45 at last follow up remained significantly higher for CKD 2b compared to CKD 2a (58.0% vs. 38.9%, p<0.001; 20.6% vs. 10.5%, p<0.001; respectively).On logistic regression for GFR<45, RN (OR 3.68, p=0.001) and CKD 2b (OR 3.3, p=0.002) were predictive. On logistic regression
for all cause mortality, RN (OR 3.76, p=0.005) and eGFR<45 (OR 2.51, p=0.029) were predictive. Similarly, after propensity matching we noted a consistently negative effect for RN compared to PN for development of eGFR <60 (64.8% vs. 35.6%, p<0.001) and eGFR <45 (23.8% vs. 9.0%, p<0.001).

Conclusion: The authors concluded that patients with baseline CKD 2, particularly CKD 2b who undergo RN, are at increased risk of GFR<45 and decreased overall survival. As such, these patients should not be considered purely elective indications for nephron-sparing surgery, and PN should be prioritized if possible.

Presented by: Zachary A. Hamilton, Saint Louis University, MO, USA

Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre, @GoldbergHanan, at the 18th Annual Meeting of the Society of Urologic Oncology, November 29-December 1, 2017 – Washington, DC
E-Newsletters

Newsletter subscription

Free Daily and Weekly newsletters offered by content of interest

The fields of GU Oncology and Urology are rapidly advancing. Sign up today for articles, videos, conference highlights and abstracts from peer-review publications by disease and condition delivered to your inbox and read on the go.

Subscribe