Comparison of patients with renal cell carcinoma in adjuvant therapy trials to a real-world population

PURPOSE: To compare characteristics and outcomes of patients included versus those not in adjuvant therapy trials post complete resection of renal cell carcinoma (RCC). METHODS: Adult patients following complete resection for clear cell RCC between January 1, 2011, and March 31, 2021, were included. Patients had intermediate high, high risk nonmetastatic disease (modified UCLA Integrated Staging System) or fully resected metastatic (M1) disease as per the inclusion criteria of adjuvant studies. Demographic, clinical, and outcomes between trial and nontrial patients were compared. RESULTS: Of 1,459 eligible patients, 63 (4.3%) participated in an adjuvant trial. Disease characteristics were similar between groups. Trial patients were younger (mean age 58.1 vs. 63.6 years; P < 0.0001) and had lower Charlson Comorbidity Index scores (mean 4.2 vs. 4.9; P = 0.009). Unadjusted disease-free survival (DFS) at 5 years for trial patients was 48.6% and 39.2% for nontrial patients (HR 0.71, 0.48-1.05, P = 0.08). Median DFS was higher for trial patients in comparison to nontrial patients (4.4 years, IQR 1.7- not reached; vs. 3.0 years, IQR 0.8-8.6; P = 0.08). Cancer specific survival (CSS) at 5 years for trial patients was 85.2% in comparison to 78.6% for nontrial patients (HR 0.45, 0.22-0.92, P = 0.03). Unadjusted estimated overall survival (OS) at 5 years was 80.8% for trial patients and 74.8% (HR 0.42, 0.18-0.94; P = 0.04) for nontrial patients. CONCLUSIONS: Patients in adjuvant trials were younger and healthier with longer CSS and OS in comparison to those not included in adjuvant trials. These findings may have implications when we generalize trial results to real world patients.