Systematic Review and Meta-Analysis of Perioperative and Oncologic Outcomes of Laparoscopic Cryoablation Versus Laparoscopic Partial Nephrectomy for the Treatment of Small Renal Tumors

Purpose: For the minimally invasive treatment of small renal tumors, laparoscopic cryoablation has emerged as an alternative procedure to minimally invasive partial nephrectomy (laparoscopic, robot-assisted laparoscopic) for selected patients, but there are still limited data regarding its safety and oncologic efficacy. We compare perioperative and oncologic outcomes of laparoscopic cryoablation and laparoscopic partial nephrectomy/robot-assisted laparoscopic partial nephrectomy. Materials and Methods: We searched the literature published until September 2013 from MEDLINE (R), Web of Science (R) and major conference proceedings. We included studies comparing laparoscopic cryoablation and laparoscopic partial nephrectomy/robot-assisted laparoscopic partial nephrectomy if they reported oncologic or perioperative outcomes. Results: Overall 13 retrospective, nonrandomized, observational studies met our inclusion criteria. According to the modified NOS (Newcastle-Ottawa Scale) 7 studies (53%) were considered to be of higher quality. Compared with laparoscopic partial nephrectomy/robot-assisted laparoscopic partial nephrectomy, laparoscopic cryoablation was associated with significantly shorter operative times (weighted mean difference [WMD] 35.45 minutes), lower estimated blood loss (WMD 130.11 ml), shorter length of stay (WMD 1.22 days), and a lower risk of total (RR 1.82), urological (RR 1.99) and nonurological complications (RR 2.33). Patients undergoing laparoscopic cryoablation had a significantly increased risk of local (RR 9.39) and metastatic tumor progression (RR 4.68). Conclusions: This analysis provides fair evidence that oncologic outcomes are substantially worse for laparoscopic cryoablation than for laparoscopic partial nephrectomy/robot-assisted laparoscopic partial nephrectomy, but laparoscopic cryoablation may be associated with improved perioperative outcomes. Therefore, surgical resection may be encouraged in the majority of cases. Balancing cancer control with the risk of perioperative complications is crucial for patient counseling and selection of the appropriate procedure. Prospective, randomized controlled studies with long-term followup are needed to confirm our findings.