Comparisons of percutaneous versus retroperitoneoscopic cryoablation for renal masses.

Purpose: Preserving renal function and controlling oncological outcomes are pertinent while managing renal tumours. We compared outcomes of percutaneous cryoablation (PCA) and retroperitoneoscopic cryoablation (RCA) in patients with renal neoplasms.

Methods: We identified 108 patients with renal tumours at two medical centres, where 63 patients received PCA and 45 patients underwent RCA from August 2009 to July 2015, and they were followed up until February 2017. We compared preoperative and postoperative parameters, namely gender, systemic diseases, age, American Society of Anesthesiologists score, body mass index (BMI), haemoglobin, the estimated glomerular filtration rate, tumour size, operative time, tumour type, Clavien-Dindo classification of surgical complications, and tumour recurrence, by using an independent sample t test, Pearson's Chi-square test, Fisher's exact test, a Mann-Whitney test, and a generalised linear model.

Results: Based on baseline characteristics, we found that the patients in the PCA group were older and had higher BMI than those in the RCA group, whereas the patients in the RCA group had more comorbidities than those in the PCA group. Retroperitoneoscopic and percutaneous methods had similar operative times, blood transfusion rates, postoperative fever episodes, and complication rates for either minor or major complications. However, the percutaneous method was associated with a shorter length of stay. No patient experienced deterioration in renal function until 2 years after both procedures. Impaired renal function was found in both groups in the 3-year follow-up. In both groups, tumour recurrence was significant for tumours > 4 cm.

Conclusions: Our results confirm that both cryoablation methods (PCA and RCA) are safe and effective for renal cell carcinoma. Favourable oncological control was achieved in both groups if the renal tumour size was ≤ 4 cm.