Renal cryoablation: five- and 10-year survival outcomes in patients with biopsy-proven renal cell carcinoma

Abstract

Objective: To investigate the long-term oncological efficacy of renal cryoablation (CA) of small renal tumors.

Materials and methods: A review of patients treated with CA for a biopsy confirmed renal cell carcinoma less than 4 cm in diameter. All patients were identified from a prospectively maintained clinical database. Treatment efficacy was computed using the Kaplan-Meier method to estimate disease-free survival (DFS) and overall survival rates (OS).

Results: A total of 179 patients (116 men and 63 women) with a mean age of 64 years (95% CI = 63 - 66) were included in the analysis. Mean tumor size was 27 mm (95% CI = 25.5-28.0) with a low, moderate and high PADUA complexity score in 30.2%, 44.7% and 16.2% of the cases, respectively. A total of 19 patients (11%) were diagnosed with residual unablated tumor, six patients (3%) were diagnosed with late local recurrence and six patients (3%) were diagnosed with metastatic disease. The estimated 5 years image confirmed the DFS rate was 79% (95% CI = 70-85). The estimated 5- and 10-year OS rates were 82% (95% CI = 75-87) and 61% (95% CI = 48-71), respectively. During the 10-year follow-up period a total of five patients (3%) died due to renal cancer, while 46 patients (26%) died from other causes.

Conclusions: CA appears to be an effective treatment modality for patients with small renal tumors. The present study demonstrated low rates of local recurrence and disease progression with excellent long-term cancer-specific survival.

Keywords: Renal cancer; renal cryoablation; small renal masses.