Prognostic and discriminative power of the 7th TNM classification for patients with surgically treated papillary renal cell carcinoma: results of a multi-institutional validation study (CORONA subtype project)

Abstract

Objective: Studies on the prognostic reliability of the Union for International Cancer Control tumor, node, metastasis (TNM) staging system for renal cell carcinoma (RCC) predominantly focus on clear-cell RCC. Therefore, the aim of this study was to investigate whether the oncological prognosis of surgically treated papillary RCC (papRCC) patients is reliably given by the current TNM system, by analyzing the largest database reported to date.

Materials and methods: Data on 2325 papRCC patients who underwent surgical treatment in 1984– 2015 were collated from 17 international centers (median follow-up 47 months). Tumor stage was adapted to the 7th edition of the TNM system. Multivariable, bootstrap-corrected Cox regression models were applied to assess the independent impact of the TNM system on cancer-specific mortality (CSM) and all-cause mortality (ACM).

Results: The median age at diagnosis was 63 years (interquartile range 54–70 years) and 77% of patients were male. Nephron-sparing surgery was performed in 42%, and 82% were with symptom free at diagnosis. In 6.7% (n = 156), organ metastasis (stage M1) was present at the time of surgery. On multivariable analysis, the TNM system and Fuhrman grade had an independent impact on both CSM and ACM, while patient age affected ACM only. The discriminative ability of the pT classification was significant for both endpoints: 5 year CSM rates were 5%, 17%, 36% and 56% for stages pT1, pT2, pT3 and pT4, respectively (each p < 0.001). The pT classification contributed significantly to the predictive accuracy of the CSM and ACM models by 6.3% and 2.5%, respectively (each p < 0.001).

Conclusions: The 2010 TNM staging system can be reliably applied to papRCC patients and allows certain prognostic discrimination.

Keywords:

• Papillary renal cell carcinoma
• predictive accuracy
• prognostic discrimination
• surgical treatment
• UICC TNM system 2010

Ethical standards

The authors ensured that the study was conducted based on accepted principles of ethical and professional conduct, and that retrospective data assessment was approved by the appropriate institutional review boards.

Disclosure statement

The authors declare that they have no conflicts of interest.

Notes on contributors

Matthias May is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Klinikum St. Elisabeth Straubing, Germany.

Cristian Surcel is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Centre of Urological Surgery, Dialysis and Renal Transplantation, Fundeni Clinical Institute, Bucharest, Romania.

Umberto Capitanio is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Vita-Salute San Raffaele University, IRCCS San Raffaele Scientific Institute, Milano, Italy.

Paolo Dell’Oglio is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Vita-Salute San Raffaele University, IRCCS San Raffaele Scientific Institute, Milano, Italy.

Tobias Klatte is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Medical University of Vienna, Austria.

Shahrokh F. Shariat is an Professor of Urology and Head of the Department of Urology, Medical University of Vienna, Austria.

Thorsten Ecke is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Hospital Bad Saarow, Germany.

Ingmar Wolff is an Urologist and a Senior Researcher at the Department of Urology, Carl-Thiem-Klinikum Cottbus, Germany.

Daniel Vergho is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Julius-Maximilians-University Medical Centre of Wuerzburg, Germany.

Nina Wagener is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, University Hospital Mannheim, Germany.

Nina Huck is an Urologist and a Senior Researcher at the Department of Urology, University Hospital Mannheim, Germany.

Sascha Pahernik is an Professor of Urology and Head of the Department of Urology, Klinikum Nürnberg, Germany.

Stefan Zastrow is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Carl Gustav Carus University Dresden, Germany.

Manfred P. Wirth is an Professor of Urology and Head of the Department of Urology, Carl Gustav Carus University Dresden, Germany.

Hendrik Borgmann is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, University Hospital Mainz, Germany.

Axel Haferkamp is an Professor of Urology and Head of the Department of Urology, University Hospital Mainz, Germany.

Mireia Musquera is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, University of Barcelona, Spain.

Laura M. Krabbe is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, University of Muenster Medical Center, Germany.

Edwin Herrmann is an Professor of Urology and a Senior Researcher at the Department of Urology, University of Muenster Medical Center, Germany.

Anna Scavuzzo is an Urologist and a Senior Researcher at the Department of Urology, Instituto Nacional de Cancerologia- INCan, Mexico City, Mexico.

Cristian Mirvald is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Centre of Urological Surgery, Dialysis and Renal Transplantation, Fundeni Clinical Institute, Bucharest, Romania.

Georg Hutterer is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Medical University Graz, Austria.

Richard Zigeuner is an Professor of Urology and a Senior Researcher at the Department of Urology, Medical University Graz, Austria.

Christian G. Stief is an Professor of Urology and Head of the Department of Urology, Ludwig-Maximilians University, Campus Grosshadern, Munich, Germany.

Raphaela Waidelich is an Professor of Urology and a Senior Researcher at the Department of Urology, Ludwig-Maximilians University, Campus Grosshadern, Munich, Germany.

Luca Cindolo is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Pio Da Pietrelcina Hospital, Vasto, Italy.

Krystina Kalusova is an Urologist and a Senior Researcher at the Department of Urology, Faculty of Medicine, Charles University, Pilsen, Czech Republic.

Sabine D. Brookman-May is an Associate Professor (Docent) of Urology and a Senior Researcher at the Department of Urology, Ludwig-Maximilians University, Campus Grosshadern, Munich, Germany.