Presentation Authors: Wei Shen Tan*, London, United Kingdom, Quoc-Dien Trinh, Boston, MA, Matthew Hayn, Portland, MA, Maya Marchese, Stuart Lipsitz, Junaid Nabi, Kerry Kilbridge, Adam Kibel, Maxine Sun, Steven Chang, Jesse Sammon, Boston, MA
Introduction: Current recommendations suggest that nephrectomy or thermal ablation is a recommended treatment option for small renal mass (â‰¤4 cm). This study examined long-term overall survival (OS) of patients managed with delayed and immediate nephrectomy of cT1a renal cancer.
Methods: We utilized the National Cancer Database (2005-2010) to identify 14,677 patients (immediate nephrectomy: 14,050 vs late nephrectomy: 627) aged â‰¤70 years with Charlson Comorbidity Index (CCI) 0 and cT1aN0M0 renal cell carcinoma (RCC). Immediate nephrectomy and late nephrectomy were defined as nephrectomy performed â‰¤30 days and â‰¥180 days from diagnosis respectively. Inverse probability of treatment weighting (IPTW)â€“adjusted Kaplan-Meier curves and Cox proportional hazards regression analyses were used to compare OS of patients in the two treatment arms. Influence of patient age and CCI on treatment effect was tested by interactions. Additional sensitivity analysis was performed to explore the outcome of delaying nephrectomy for â‰¥12 months. Post-hoc power calculations were performed.
Results: Median age of patients were 55 years with a median follow-up of 82.5 months. IPTW-adjusted Kaplan-Meier curves suggest not significant difference between treatment arms (Hazard ratio, 0.96; 95% confidence interval, 0.73 to 1.26; p=.77). This outcome was consistent between all patients regardless of age (p=.48). Sensitivity analysis report no difference in overall survival even if nephrectomy was delayed by â‰¥12 months (p=.60).
Conclusions: We report that delayed and immediate nephrectomy for cT1a RCC confers comparable long-term overall survival. The findings of this study support the use of surveillance as a first-line management strategy for small renal masses.