To investigate prognostic parameters for the oncological outcome of patients treated for chromophobe RCC (chRCC) in comparison to patients treated for clear cell RCC (ccRCC) using propensity score matching for survival analysis.
From 1969 to 2009 we identified 1010 from 3567 patients with RCC. Survival was analyzed using Kaplan-Meier estimate for histological subtypes including 109 chRCC and 901 ccRCC. Uni- and multivariate Cox regression was used to analyze prognostic factors for overall survival (OS) and cancer specific survival (CSS). Propensity score matching was performed to adjust for differences in patient characteristics amongst histological subgroups.
The median follow-up was 61 months (range 0-289). chRCC showed longer OS (5 year 90.1%, 10 year 74.2%, 15 year 61.4%) and CSS (94.2%, 89.7%, 89.7%) compared to ccRCC (OS 75.7%, 54.9%, 46.1% and CSS 84.7%, 75.4%, 72.2%; p=0.002). Multivariate Cox-regression revealed histology as a significant prognostic factor. Propensity score matching showed a difference in 72.4% (OS) and 87.2% (CSS) of matching attempts confirming the significant impact of histology. Univariate Cox regression showed: nephron sparing surgery, no metastasis and no symptoms at presentation, age <65, eosinophilic features, low ASA score and Charlson Comorbidity Index (CCI) to be beneficial for CSS. Only age at surgery, metastasis at presentation, ASA and CCI-score were significant factors for OS in chRCC patients.
ChRCC appears to have a favorable outcome compared to ccRCC. Even after adjustment for differences in characteristics known to have an influence on survival by propensity score matching, histology remains a significant prognostic factor.
Urology. 2016 Jun 01 [Epub ahead of print]
S Frees, M M Kamal, L Knoechlein, R Bell, C Ziesel, A Neisius, C Thomas, W Brenner, W Jäger, J W Thüroff, F C Roos
Department of Urology, University Medical Center, Mainz, Germany; Department of Urologic Sciences, Vancouver Prostate Centre, University of British Columbia, Vancouver, Canada., Department of Urology, University Medical Center, Mainz, Germany; Urology and Nephrology Center, Mansoura, Egypt., Department of Urology, University Medical Center, Mainz, Germany., Department of Urologic Sciences, Vancouver Prostate Centre, University of British Columbia, Vancouver, Canada., Department of Urology, University Medical Center, Mainz, Germany., Department of Urology, University Medical Center, Mainz, Germany., Department of Urology, University Medical Center, Mainz, Germany., Department of Urology, University Medical Center, Mainz, Germany., Department of Urology, University Medical Center, Mainz, Germany., Department of Urology, University Medical Center, Mainz, Germany., Department of Urology, University Medical Center, Mainz, Germany. Electronic address: .