Recent trials have emphasized the importance of a precise patient selection for cytoreductive nephrectomy (CN). In 2013, a nomogram was developed for pre- and postoperative prediction of the probability of death (PoD) after CN in patients with metastatic renal cell carcinoma. To date, the single-institutional nomogram which included mostly patients from the cytokine era has not been externally validated. Our objective is to validate the predictive model in contemporary patients in the targeted therapy era.
Multi-institutional European and North American data from patients who underwent CN between 2006 and 2013 were used for external validation. Variables evaluated included preoperative serum albumin and lactate dehydrogenase levels, intraoperative blood transfusions (yes/no) and postoperative pathologic stage (primary tumour and nodes). In addition, patient characteristics and MSKCC risk factors were collected. Using the original calibration indices and quantiles of the distribution of predictions, Kaplan-Meier estimates and calibration plots of observed versus predicted PoD were calculated. For the preoperative model a decision curve analysis (DCA) was performed.
Of 1108 patients [median OS of 27 months (95% CI 24.6-29.4)], 536 and 469 patients had full data for the validation of the pre- and postoperative models, respectively. The AUC for the pre- and postoperative model was 0.68 (95% CI 0.62-0.74) and 0.73 (95% CI 0.68-0.78), respectively. In the DCA the preoperative model performs well within threshold survival probabilities of 20-50%. Most important limitation was the retrospective collection of this external validation dataset.
In this external validation, the pre- and postoperative nomograms predicting PoD following CN were well calibrated. Although performance of the preoperative nomogram was lower than in the internal validation, it retains the ability to predict early death after CN.
World journal of urology. 2018 Aug 01 [Epub ahead of print]
Lorenzo Marconi, Roderick de Bruijn, Erik van Werkhoven, Christian Beisland, Kate Fife, Axel Heidenreich, Anil Kapoor, Jose Karam, Caroline Kauffmann, Tobias Klatte, Boerje Ljungberg, Surena Matin, Daniel Sjoberg, Michael Staehler, Grant D Stewart, Simon Tanguay, Robert Uzzo, Sarah Welsh, Lori Wood, Chris Wood, Axel Bex
Department of Urology, Coimbra University Hospital, Coimbra, Portugal., Division of Surgical Oncology, Department of Urology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands., Department of Urology, Haukeland University Hospital, Bergen, Norway., Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK., Department of Urology, University Hospital Cologne, Cologne, Germany., Department of Surgery, McMaster University, Hamilton, Canada., The University of Texas MD Anderson Cancer Center, Houston, TX, USA., Department of Urology, Medical University of Vienna, Vienna, Austria., Department of Urology, Umeå University, Umea, Sweden., Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, USA., University Hospital Munich-Grosshadern, Ludwig Maximilian University, Munich, Germany., Department of Urology, McGill University, Montreal, Canada., Fox Chase Cancer Center, Temple University Health System, Philadelphia, PA, USA., Queen Elizabeth II Health Science Centre, Halifax, Canada., Division of Surgical Oncology, Department of Urology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands. .