Impact of tumor histology and grade on treatment success of percutaneous renal cryoablation.
Academic Article
Overview
abstract
BACKGROUND: We analyzed oncological outcomes in patients who underwent percutaneous renal cryoablation (PRC) with documented renal cell carcinoma (RCC) by perioperative biopsy. METHODS: Multicenter retrospective analysis of 153 patients [median follow-up 48 months] who underwent PRC from 09/2005 to 08/2014 was performed. We divided the cohort into patients who developed recurrence versus no recurrence. Kaplan-Meier analyses examined recurrence-free survival (RFS) according to grade and histology. Multivariable analysis (MVA) was performed to identify factors associated with tumor recurrence. RESULTS: One hundred and fifty-three patients were analyzed [18 patients (11.8 %) with recurrence and 135 (88.2 %) patients without recurrence]. There were no differences between the groups with respect to demographics, RENAL score, and number of probes utilized. Recurrence group had larger tumor size (3.1 vs. 2.4 cm; p = 0.011), upper pole tumor location (p = 0.016), and greater proportions of high-grade tumor (33 vs. 0.7 %; p < 0.001) and clear cell histology (77.8 vs. 45.9 %; p = 0.011). Four-year RFS was 100 versus 80 % for grade 1 versus grade 2/3 tumors (p = 0.0002), and 97 versus 88 % for other RCC versus clear cell RCC (p = 0.07). MVA demonstrated tumor size >3 cm (OR 2.46; p = 0.019), clear cell histology (OR 2.12; p = 0.027), and high tumor grade (OR 2.33, p < 0.001) as independent risk factors associated with tumor recurrence. CONCLUSIONS: Association of higher grade and clear cell histology with recurrence and progression suggests need for increased emphasis on preoperative risk stratification by biopsy, with grade 1 and non-clear cell RCC being associated with improved treatment success than higher grade and clear cell RCC.
