The impact of lymph node dissection and positive lymph nodes on cancer specific mortality in contemporary pT2-3 non-metastatic renal cell carcinoma treated with radical nephrectomy

To assess the effect of lymph node dissection (LND), number of removed nodes (NRN) and number of positive nodes (NPN) on cancer specific mortality (CSM), in contemporary vs. historical patients, with pT2-3 Nany M0 renal cell carcinoma (RCC) treated with radical nephrectomy (RN).

Within the SEER database (2001-2013), we identified patients with non-metastatic pT2-3 Nany RCC who underwent RN with or without LND. Kaplan-Meier analyses and multivariable Cox regression models with propensity score weighting for inverse probability of treatment were used.

Of 25,357 patients, 24.8% underwent lymph node dissection (2001-2007: 3,167 patients vs. 2008-2013: 3,133 patients). Median NRN was 3 (IQR 1-7). Positive nodes were identified in 17.1%: 9.3% of pT2 and 21.6% of pT3 patients, who underwent LND. Median NPN was 2 (IQR 1-2). In multivariable models, LND did not decrease CSM (HR 1.29, p<0.001). LND extent, defined as NRN, did not decrease CSM (HR: 0.94, p=0.3). Finally, multivariable models testing the effect of NPN showed increased CSM, in pT3 but not in pT2 patients (HR:1.29 and 1.58, p=0.02 and 0.1, respectively). NRN exerted a protective effect on CSM in patients with positive nodes (HR:0.98; p=0.007).

In contemporary and historical patients LND or its extent, do not protect from CSM. However, the NPN increases the rate of CSM in pT3 patients. In consequence, LND and its extent appear to have little or any therapeutic value in pT2-3 Nany M0 patients, besides its prognostic impact. High risk non-metastatic patients may represent a target population for a multi-institutional prospective trial. This article is protected by copyright. All rights reserved.

BJU international. 2017 Sep 20 [Epub ahead of print]

Michele Marchioni, Marco Bandini, Raisa S Pompe, Tristan Martel, Zhe Tian, Shahrokh F Shariat, Anil Kapoor, Luca Cindolo, Alberto Briganti, Luigi Schips, Umberto Capitanio, Pierre I Karakiewicz

Department of Urology, SS Annunziata Hospital, "G. D'Annunzio" University of Chieti, Chieti, Italy., Cancer Prognostics and Health Outcomes Unit, University of Montreal Health Center, Montreal, Quebec, Canada., Department of Urology, Medical University of Vienna, Vienna, Austria., Division of Urology, McMaster University, Hamilton, Ontario, Canada., Department of Urology, ASL Abruzzo 2, Chieti, Italy., Division of Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan, Italy.