Laparoscopic cryoablation vs. percutaneous cryoablation for treatment of small renal masses: a systematic review and meta-analysis
PURPOSE To determine the effectiveness and complication rates of ablation of renal cell carcinoma (RCC) performed with a percutaneous approach versus a surgical approach. MATERIALS AND METHODS A search performed on PubMed identified series of renal tumor ablations. Keywords searched included "radiofrequency" (RF), "cryoablation", "cryosurgery", "cryotherapy", "ablation", "renal", "kidney", and "RCC". Review articles were excluded from the search of English-language literature from January 1996 through August 2006. Inclusion criteria were (i) more than one case, (ii) use of RF ablation or cryoablation, (iii) effectiveness based on follow-up imaging, and (iv) report of complication rate. Effectiveness was defined by the proportion of tumors without residual enhancement after one treatment session (ie, primary effectiveness) or after repeated treatments (ie, secondary effectiveness). Major complications were defined as events with substantial morbidity, disability, or increasing level of care. Metaanalysis was performed on primary effectiveness, secondary effectiveness, and major complication rates with a random-effects model. Differences were considered significant if the 95% CIs did not overlap. RESULTS Forty-six series (28 percutaneous, 18 surgical) met all inclusion criteria. The primary effectiveness rate for the percutaneous group (87%) was significantly lower than that in the surgical group (94%; P < .05). The secondary effectiveness rate in the percutaneous treatment group (92%) was not significantly different from that in the surgical treatment group (95%; P > .05). The major complication rate in the percutaneous treatment group (3%) was significantly lower than that in the surgical treatment group (7%; P < .05). CONCLUSIONS Based on a metaanalysis, when ablating renal tumors, a percutaneous approach was safer than an open or laparoscopic approach and was equally effective. However, more than one procedure was needed to treat the tumor completely.