The study team utilized the National Cancer Database to identify patients between 2006 and 2016 with metastatic RCC who received either cytoreductive nephrectomy, targeted therapy, or both. They excluded patients who had any history of other prior cancer. The study team evaluated the incidence of patients receiving cytoreductive nephrectomy and targeted therapy [in that order] versus those who received cytoreductive nephrectomy and targeted therapy, using overall survival and cancer-specific mortality as their primary endpoints.
The study team used Kaplan Meier and Cox regression analyses to compare the groups for overall survival. Propensity score matching was also used to compare baseline characteristics for age, sex, race, comorbidity index, incoming quartile, education, county of residence, treatment facility location and type, primary tumor histology, and clinical t- and n-stage. Probabilities of receiving targeted treatment post-cytoreductive nephrectomy and cytoreductive nephrectomy post-targeted treatment were evaluated in competing risk analyses. The study team found that physicians were more likely to treat patients with high grade cancer with surgery prior to targeted therapy, which was found to be statistically significant (p<0.001). They also found that physicians were more likely to perform targeted therapy prior to surgery when they had a clinical-n stage of 1 (p<0.001).
By six months after initial cytoreductive nephrectomy, 48% of patients received subsequent targeted therapy, while 15.3% died before receiving targeted therapy. In patients who received initial targeted therapy, by 6 months, 4.7% underwent cytoreductive nephrectomy while 44.9% died prior. Patients who were treated at academic centers were more likely to undergo cytoreductive nephrectomy prior to initial targeted therapy.
The study team would like to note limitations. The study did have an observational design and used the NCDB, which is known to have an incomplete capture of therapies after 6 months. They would like to note this previously discussed limitation did not impact the current finding as they were looking at initial treatment for RCC metastatic patients. In conclusion, the study team finds that initial cytoreductive nephrectomy versus initial targeted therapy was associated with improved survival. Patients in both groups did have delay in subsequent therapy. They also found a variance in practice pattern in the centers and regional variance across the dataset. Finally, the urge further studies to establish the optimal multimodal approach for metastatic RCC.
Presented by: Bimal Bhindi, MD
Co-Authors: Elizabeth Habermann, Ross Mason, Brian Costello, Lance Pagliaro, Houston Thompson, Bradley Leibovich, Stephen Boorjian, Rochester, MN
Written by: Anthony Warner, AS, Department of Urology, University of California-Irvine medical writer for UroToday.com at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA