Percutaneous Clinical T_1a Renal Mass Ablation in the Octogenarian and Nonagenarian: Oncologic Outcomes and Morbidity

Purpose: To evaluate outcomes of percutaneous ablation of small renal tumors in the elderly population. Patients and Methods: Using our tumor ablation database, we searched for percutaneous ablation procedures for clinical T_1a renal masses in octogenarians and nonagenarians between June 2001 and May 2012. Altogether, 105 tumors from 99 procedures among 95 patients (mean age 84.0±3.0 years, range 80-92) were identified. Oncologic outcomes and major complications were evaluated. Assessment also included patient hospital stays and renal functional outcomes. Results: Technical success was achieved in 60/61 (98.4%) tumors managed with cryoablation and 43/44 (97.7%) after radiofrequency ablation (RFA). Of 87 renal tumors with at least 3 months imaging follow-up, 2 (5.4%) tumors progressed at 1.2 and 2.2 years after RFA. None recurred after cryoablation. Estimated progression-free survival rates at 1, 3, and 5 years after ablation were 99%, 97%, and 97%, respectively. Thirty-four patients died at a mean of 3.7 years after ablation (median 3.7; range 0.4-9.6). Estimated overall survival rates were 98%, 83%, and 61%, respectively. Among 33 patients with sporadic, biopsy-proven renal-cell carcinoma, estimated cancer-specific survival rates were 100%, 100%, and 86%, respectively. Five (8.6%) major complications developed after renal cryoablation with no (0%) major complication after RFA. Mean decrease in serum creatinine level within 1 week after ablation was 0.1mg/dL. Mean hospitalization was 1.2 days. Conclusion: Percutaneous thermal ablation is safe and effective in the active management of clinical T_1a renal masses in elderly patients. These results should help urologists appropriately assess expected outcomes when counseling octogenarian and nonagenarian patients.