Utilization of local treatment modalities and surveillance in veterans with early stage renal cell carcinoma.

Abstract

643 Background: Surgery represents the standard treatment for early stage renal cell carcinoma (RCC). For older patients, especially those with comorbidities including chronic kidney disease (CKD), there have been efforts made to spare renal function. The objective of this study was to evaluate the disease and treatment characteristics of Veterans with early stage RCC. Methods: We used the national Veterans Affairs’ Corporate Data Warehouse (CDW) database to identify patients diagnosed between 2000-2018 with early stage (cT1-2N0M0) RCC. Laboratory and diagnosis data were used to calculate creatinine clearance and Charlson comorbidity score. Chronic kidney disease (CKD) was defined as creatinine clearance < 60 milliliters per minute. The odds of receiving surveillance were evaluated with multivariable logistic regression. Results: Overall 19,555 Veterans with early stage RCC were included. The median age at diagnosis was 65, 90% range (48-82). 9,807 patients (50%) had at least 1 comorbidity and 4169 (21%) had multiple. Of 16,514 (84%) patients with available lab data, 1,359 (8%) patients had CKD. The treatments received were radical nephrectomy (RN) (N=4107, 21%), nephron sparing surgery (NSS) (N=5008, 26%), thermal ablation (N=489, 3%), and surveillance (N=9946, 51%). Compared to 2000-2010, from 2011-2018, there was a higher proportion of patients receiving NSS (29% vs. 20%, p < 0.01) and a lower proportion receiving surveillance (49% vs. 54%, p < 0.01). On multivariable logistic regression, predictors of receiving surveillance included older age (Odds Ratio [OR] 1.03 per year, p<0.01), T1 disease (OR 1.18, 95% CI 1.08-1.28), increasing number of comorbidities (OR 1.12 per comorbidity point, 95% CI 1.08-1.16), or CKD (OR 1.25, 95% CI 1.12-1.41). Compared to creatinine clearance before diagnosis, the median change in creatinine clearance at least 1 year after diagnosis was -46 for RN, -9 for NSS, -8 for ablation, and -24 for surveillance (p<0.01). Conclusions: A significant proportion of Veterans with early stage RCC undergo surveillance. Nephron sparing treatments are becoming increasingly common and are associated with more modest reductions in renal function than radical nephrectomy or surveillance. Further studies are warranted to assess the impact of surveillance on survival and cancer related outcomes.