A comparison of percutaneous cryosurgery and percutaneous radiofrequency for unresectable hepatic malignancies. Intraoperative radiofrequency ablation or cryoablation for hepatic malignancies. Cryosurgical ablation and radiofrequency ablation for unresectable hepatic malignant neoplasms: a proposed algorithm.
The complication and success rates in patients treated with either percutaneous cryosurgery (PCS) or percutaneous radiofrequency (PRF) for unresectable hepatic malignancies are similar.
                Retrospective study.
                University hospital.
                Sixty-four patients were treated with either PCS (n = 31) or PRF (n = 33). Patient treatment was based on the random availability of the probes. Tumors were evaluated by a blinded comparison of pretreatment and posttreatment helical computed tomographic scans. All living patients had at least a 6-month follow-up.
                Complication rate, initial treatment success (complete devascularization of the tumor), and local recurrence (tumor revascularization within or at its periphery).
                The distribution of tumor types was similar in the 2 groups (P =.76). One patient with cirrhosis died of variceal hemorrhage on day 30 after PCS (mortality, 3.2%), while no mortality was observed after PRF (P =.48). Complications occurred in 9 (29%) of the patients following PCS and in 8 (24%) of the patients following PRF (P =.66). Initial treatment success was comparable in the 2 treatment groups (30 [83%] of 36 tumors following PCS vs 34 [83%] of 41 tumors following PRF). However, local recurrences occurred more frequently after PCS than after PRF (16 [53%] of 30 vs 6 [18%] of 34; P =.003). The higher rate of local recurrence was identified for metastases (10 [71%] of 14 after PCS vs 3 [19%] of 16 after PRF; P =.004), while the difference was not significant for hepatocellular carcinoma (6 [38%] of 16 after PCS vs 3 [17%] of 18 after PRF; P =.25). Multivariate analysis demonstrated that the use of PCS (P =.003) and more than 1 treatment (P =.05) were independent risk factors for local tumor recurrence.
                While similar initial treatment success and complication rates are observed following either PCS or PRF, local recurrences occur more frequently following PCS, particularly for metastases. The majority of patients with primary or metastatic malignancies confined to the liver are not candidates for resection because of tumor size, location, multifocality, or inadequate functional hepatic reserve. Cryoablation has become a common treatment in select groups of these patients with unresectable liver tumors. However, hepatic cryoablation is associated with significant morbidity. Radiofrequency ablation (RFA) is a technique that destroys liver tumors in situ by localized application of heat to produce coagulative necrosis. In this study, we compared the complication and early local recurrence rates in patients with unresectable malignant liver tumors treated with either cryoablation or RFA.
                Patients with hepatic malignancies were entered into two consecutive prospective, nonrandomized trials. The liver tumors were treated intraoperatively with cryoablation or RFA; intraoperative ultrasonography was used to guide placement of cryoprobes or RFA needles. All patients were followed up postoperatively to assess complications, treatment response, and local recurrence of malignant disease.
                Cryoablation was performed on 88 tumors in 54 patients, and RFA was used to treat 138 tumors in 92 patients. Treatment-related complications, including 1 postoperative death, occurred in 22 of the 54 patients treated with cryoablation (40.7% complication rate). In contrast, there were no treatment-related deaths and only 3 complications after RFA (3.3% complication rate, P<0.001). With a median follow-up of 15 months in both patient groups, tumor has recurred in 3 of 138 lesions treated with RFA (2.2%), versus 12 of 88 tumors treated with cryoablation (13.6%, P<0.01).
                RFA is a safe, well-tolerated treatment for patients with unresectable hepatic malignancies. This study indicates that (1) complications occur much less frequently following RFA of liver tumors compared with cryoablation of liver tumors, and (2) early local tumor recurrence is infrequent following RFA. Thermal ablation of unresectable hepatic tumors can be achieved by cryosurgical ablation (CSA) or radiofrequency ablation (RFA). The relative advantages and disadvantages of each technique have not yet been determined.
                Radiofrequency ablation of malignant hepatic neoplasms can be performed safely, but is currently limited by size. Cryosurgical ablation, while associated with higher morbidity, is more effective for larger unresectable hepatic malignant neoplasms.
                Retrospective analysis of prospective patient database.
                Between July 1992 and September 1999, 308 patients with liver tumors not amenable to curative surgical resection were treated with CSA and/or RFA (percutaneous, laparoscopic, celiotomy). No patient had preoperative evidence of extrahepatic disease. All patients underwent laparoscopy with intraoperative ultrasound if technically possible. Both RFA and CSA were performed under ultrasound guidance. Resection, as an adjunctive procedure, was combined with ablation in certain patients.
                Laparoscopy identified extrahepatic disease in 12% of patients, and intraoperative hepatic ultrasound identified additional lesions in 33% of patients, despite extensive preoperative imaging. Radiofrequency ablation alone or combined with resection or CSA resulted in reduced blood loss (P<.05), thrombocytopenia (P<.05), and shorter hospital stay compared with CSA alone (P<.05). Median ablation times for lesions greater than 3 cm were 60 minutes with RFA and 15 minutes with CSA (P<.001). Local recurrence rates for lesions greater than 3 cm were also greater with RFA (38% vs 17%).
                Laparoscopy and intraoperative ultrasound are essential in staging patients with hepatic malignant neoplasms. Radiofrequency ablation when combined with CSA reduces the morbidity of multiple freezes. Although RFA is safer than CSA and can be performed via different approaches (percutaneously, laparoscopically, or at celiotomy), it is limited by tumor size (<3 cm). Percutaneous RFA should be considered in high-risk patients or those with small local recurrences.
At present, there is no evidence to recommend or refute cryotherapy for patients with hepatocellular carcinoma. Randomised clinical trials with low-risk of bias may help in defining the role of cryotherapy in the treatment of hepatocellular carcinoma.