41 UNDERSTANDING THE COMPARATIVE EFFECTIVENESS OF LAPAROSCOPIC RADICAL NEPHRECTOMY FOR PATIENTS WITH KIDNEY CANCER

Abstract

INTRODUCTION AND OBJECTIVES: Although laparoscopic radical nephrectomy (LRN) is now a preferred treatment for many patients with kidney cancer, there is limited population-based data evaluating its comparative effectiveness relative to open radical nephrectomy (ORN). In this context, we compared recent trends in hospital-based outcomes among a nationally-representative sample of Medicare beneficiaries undergoing LRN vs. ORN. METHODS: Using linked SEER-Medicare data, we identified a population-based sample of patients treated with LRN or ORN for non-urothelial, non-metastatic kidney cancer from 2000 through 2005. For each patient, we measured an array of demographic (e.g., age), clinical (e.g., Charlson comorbidity index), and cancer-specific (e.g., tumor size and stage) characteristics. Next, we defined the following outcomes: ICU admission; prolonged length of stay (LOS); readmission within 30 days; and in-hospital mortality. We then fit multivariable logistic regression models to estimate the association between type of surgery and each clinical outcome, adjusting for measurable patient characteristics and year of surgery. RESULTS: Among our analytic sample, 2,108 (26%) and 5,895 (74%) patients underwent treatment with LRN and ORN, respectively. Patients treated with LRN were more likely to be White, female, of higher socioeconomic position, and to have a tumor size 4 cm (all p-values 0.05). After adjusting for demographic, clinical and tumor characteristics, the probability of ICU admission and prolonged LOS was 42.4% and 46.6% lower, respectively, for patients undergoing LRN vs. ORN (Figure, p 0.001). Conversely, although still uncommon, the adjusted probability of in-hospital mortality was 52% (p 0.041) higher for patients treated with a laparoscopic vs. open approach (Figure). CONCLUSIONS: In this population-based sample, patients treated with LRN had a lower likelihood of ICU admission and prolonged LOS, findings that support the convalescence benefits of laparoscopy. That in-hospital mortality was higher among patients treated with LRN suggests a potentially unanticipated consequence of this minimally-invasive technique and highlights the need for long-term monitoring following diffusion of new surgical technologies. Source of Funding: Edwin Beer Research Fellowship