Clinical Outcomes of Patients With Nondiagnostic Biopsy During Cryoablation of Small Renal Masses

Abstract

OBJECTIVE To compare the outcomes of patients with biopsy-proven renal cell carcinoma (RCC), benign tumors (BTs), and nondiagnostic (ND) biopsies after renal cryoablation (RC).METHODS We retrospectively reviewed medical records of 114 patients who underwent RC between 2003 and 2013. Patients were stratified according to biopsy histopathology results-RCC, BT, and ND biopsy. We recorded patient demographics and tumor features and examined oncologic outcomes among the 3 groups.RESULTS RC was performed in 114 patients with 117 tumors. Seventy-two tumors (61.5%) were RCC, 18 (15.4%) were BTs (oncocytoma or angiomyolipoma), and 27 (23.1%) were ND. Patient characteristics and tumor features were similar among the 3 groups. the median follow-up was 26.5, 26.0, and 22.0 months in the RCC, BT, and ND biopsy groups, respectively (P = .18). Residual disease occurred in the RCC (1.4%) and ND biopsy (7.4%) groups, but not in the BT group (P = .19). All 9 patients (12.5%) who developed recurrent disease had biopsy-proven RCC. the 2- and 5-year recurrence-free survival rates (RFS) for patients with biopsy-proven RCC were 90.2% and 81.2%, respectively. Because no patient in the BT and ND biopsy groups had a recurrence, their RFS was 100%.CONCLUSION No patient with a BT or ND biopsy developed a local recurrence with short-term follow-up, whereas a recurrence developed in 12.5% of biopsy-proven RCC tumors. RFS for patients with biopsy-proven RCC was worse than the other 2 biopsy groups, although not statistically significant. Long-term follow-up in a larger cohort of patients is needed to further evaluate these preliminary findings. (C) 2015 Elsevier Inc.