SUO 2017: Cytoreductive Nephrectomy In Patients With Metastatic Renal Cell Carcinoma And Tumor Thrombus – Trends And Effect On Overall Survival

Washington, DC (UroToday.com) Dr. Lenis and colleagues presented their population-based research this afternoon at the 2017 SUO annual winter meeting in Washington DC, discussing trends and effect on overall survival for patients undergoing cytoreductive nephrectomy for patients with concomitant tumor thrombus. Although patients with metastatic renal cell carcinoma (mRCC) commonly present with tumor thrombi in the renal vein and/or inferior vena cava (IVC), the use of cytoreductive nephrectomy in this population is controversial and the effect on overall survival (OS) is unknown. As such, the objective of this study was to assess the impact of cytoreductive nephrectomy in this population.

The authors identified 9,015 patients with mRCC between 2010 and 2013 in the National Cancer Database (NCDB), defined as T3a (renal vein), T3b (IVC below the diaphragm), or T3c (above the diaphragm). Descriptive statistics were performed and associations between clinicopathologic variables and utilization of cytoreductive nephrectomy were analyzed. Kaplan Meier analyses and multivariable Cox proportional hazards models were used to estimate survival. Among these patients, 28% (n=2,487) had tumor thrombi (79% T3a, 16% T3b, 6% T3c). Median OS was 16, 15, and 11 months for patients with mRCC and T3a, T3b, and T3c disease, respectively. Cytoreductive nephrectomy was performed in 76%, 71%, and 60% of patients with T3a, T3b, and T3c disease, respectively. Independent predictors of cytoreductive nephrectomy in this cohort included treatment at an academic or research facility, East Central US region, non-clear cell histology, high-grade disease, concurrent metastasectomy, and more recent year of treatment. Patients with T3b and T3c were significantly less likely to undergo cytoreductive nephrectomy than patients with T3a disease. On multivariable analysis controlling for patient and tumor specific variables, cytoreductive nephrectomy was associated with improved OS (HR 0.36, 95%CI 0.31–0.42, p<0.001) in patients with mRCC and tumor thrombi. However, this effect was limited to those with T3a disease (HR 0.34, 95% CI 0.29–0.41, p<0.01) and T3b disease (HR 0.31, 95% CI 0.20–0.50, p<0.01) disease, but not T3c (HR 0.62, 95% CI 0.31–1.21, p=0.16) disease.

The authors concluded that OS for this patient population is poor and various factors influence the use of CN, including clinicodemographic and tumor specific variables. Despite discrepancies in utilization, CN is associated with improved OS, although this effect appears to be limited to those with mRCC and tumor thrombus limited to the renal vein and infra-diaphragmatic IVC.

Speaker: Andrew Lenis, Department of Urology, UCLA, Los Angeles, CA

Co-Authors: Claire Burton, Izak Faiena, Amirali Salmasi, Aydin Pooli, David Johnson, Alexandra Drakaki, Kiran Gollapudi, Jeremy Blumberg, Allan Pantuck, Karim Chamie

Written by: Zachary Klaassen, MD, Urologic Oncology Fellow, University of Toronto, Princess Margaret Cancer Centre, @zklaassen_md, at the 18th Annual Meeting of the Society of Urologic Oncology, November 29-December 1, 2017 – Washington, DC