Recent publications have reported an association between increased renal cancer-specific mortality (CSM) and reduced renal function "below safety limits," and advocated for partial nephrectomy (PN) even for potentially aggressive/complex tumors.
We hypothesize that this association may be related to confounding factors rather than a consequence of functional differences.
To assess whether there is an independent association between preoperative estimated glomerular filtration rate (eGFR) or new baseline eGFR (NB-GFR) and CSM in patients undergoing PN or radical nephrectomy (RN).
A single-center retrospective review was performed. All clinically and pathologically confirmed T1-T3a/N0/M0 renal cancer patients undergoing PN/RN (1999-2008, n = 1605) with adequate functional/oncological data were included.
The primary endpoint was CSM. Secondary endpoints were cancer recurrence (CR) and all-cause mortality (ACM). Cox regression analyses investigated endpoints and predictive factors.
The median age was 60 yr and 64% of patients were male. Comorbidities included hypertension (60%), cardiovascular disease (19%), diabetes (21%), and chronic kidney disease (22%). PN was performed in 954 patients (59%). The median preoperative eGFR and NB-GFR were 80 and 60 ml/min/1.73 m2, respectively. Median tumor diameter was 3.6 cm (interquartile range [IQR] = 2.4, 5.5); 70% of tumors were clear cell and 40% were of high grade. Pathology revealed pT1-2/N0/M0 and pT3a/N0/M0 in 81% and 19%, respectively. The median follow-up among survivors was 11.5 yr (IQR = 4, 14). Cancer-specific survival, recurrence-free survival, and overall survival were 94%, 88%, and 73% at 10 yr, respectively. On multivariable analysis, increased age (hazard ratio [HR] = 1.03, p = 0.04), increased tumor size (HR = 1.24, p < 0.01), tumor grade 3/4 (HR = 3.17, p < 0.01), and clear-cell histology (HR = 2.92, p < 0.01) were associated with increased hazard of CSM. Neither preoperative eGFR nor NB-GFR was significantly associated with CSM or CR (all p > 0.1), while an increased preoperative eGFR was associated with reduced hazard of ACM (HR = 0.87, p < 0.01). Limitations include retrospective design and a potential selection bias.
Our data do not support oncological protection of greater preservation of renal function and confirm that unfavorable oncological outcomes for localized RCC are mostly associated with aggressive tumor characteristics.
We did not find an association between greater preservation of renal function and oncological outcomes for kidney cancer.
European urology. 2021 Mar 04 [Epub ahead of print]
Diego Aguilar Palacios, Emily C Zabor, Carlos Munoz-Lopez, Gustavo Roversi, Furman Mahmood, Emily Abramczyk, Maureen Kelly, Brigid Wilson, Robert Abouassaly, Steven C Campbell
Glickman Urological and Kidney Institute, Cleveland Clinic Foundation, Cleveland, OH, USA., Department of Quantitative Health Sciences & Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA., Case Western Reserve University School of Medicine, Cleveland, OH, USA; Louis Stokes Veteran's Affairs Medical Center, Cleveland, OH, USA., Glickman Urological and Kidney Institute, Cleveland Clinic Foundation, Cleveland, OH, USA; Louis Stokes Veteran's Affairs Medical Center, Cleveland, OH, USA., Glickman Urological and Kidney Institute, Cleveland Clinic Foundation, Cleveland, OH, USA. Electronic address: .