Rates and patterns of recurrence for percutaneous radiofrequency ablation and open wedge resection for solitary colorectal liver metastasis. Recurrence and outcomes following hepatic resection, radiofrequency ablation, and combined resection/ablation for colorectal liver metastases. Radiofrequency ablation for metachronous liver metastasis from colorectal cancer after curative surgery. Solitary colorectal liver metastasis: resection determines outcome. Hepatectomy is superior to thermal ablation for patients with a solitary colorectal liver metastasis. Colorectal liver metastases: recurrence and survival following hepatic resection, radiofrequency ablation, and combined resection-radiofrequency ablation. Feasibility of adjuvant hepatic arterial infusion of chemotherapy after radiofrequency ablation with or without resection in patients with hepatic metastases from colorectal cancer. Resection versus laparoscopic radiofrequency thermal ablation of solitary colorectal liver metastasis. Radiofrequency ablation as first-line treatment in patients with early colorectal liver metastases amenable to surgery. Role of intraoperative thermoablation combined with resection in the treatment of hepatic metastasis from colorectal cancer. [Radiofrequency ablation of colorectal liver metastases]. Radiofrequency ablation vs. resection for hepatic colorectal metastasis: therapeutically equivalent? Long-term outcomes following hepatic resection and radiofrequency ablation of colorectal liver metastases. Comparison of resection and radiofrequency ablation for treatment of solitary colorectal liver metastases. Clinical outcomes of hepatic resection and radiofrequency ablation in patients with solitary colorectal liver metastasis. Comparative analysis of radiofrequency ablation and surgical resection for colorectal liver metastases. Comparative study of resection and radiofrequency ablation in the treatment of solitary colorectal liver metastases.
The purpose of this study was to compare rates and patterns of disease progression following percutaneous, image-guided radiofrequency ablation (RFA) and nonanatomic wedge resection for solitary colorectal liver metastases.
                We identified 30 patients who underwent nonanatomic wedge resection for solitary liver metastases and 22 patients who underwent percutaneous RFA because of prior major hepatectomy (50%), major medical comorbidities (41%), or relative unresectability (9%). Serial imaging studies were retrospectively reviewed for evidence of local tumor progression.
                Patients in the RFA group were more likely to have undergone prior liver resection, to have a disease-free interval greater than 1 year, and to have had an abnormal carcinoembryonic antigen (CEA) level before treatment. Two-year local tumor progression-free survival (PFS) was 88% in the Wedge group and 41% in the RFA group. Two patients in the RFA group underwent re-ablation, and two patients underwent resection to improve the 2-year local tumor disease-free survival to 55%. Approximately 30% of patients in each group presented with distant metastasis as a component of their first recurrence. Median overall survival from the time of resection was 80 months in the Wedge group vs 31 months in the RFA group. However, overall survival from the time of treatment of the colorectal primary was not significantly different between the two groups.
                Local tumor progression is common after percutaneous RFA. Surgical resection remains the gold standard treatment for patients who are candidates for resection. For patients who are poor candidates for resection, RFA may help to manage local disease, but close follow-up and retreatment are necessary to achieve optimal results. To examine recurrence and survival rates for patients treated with hepatic resection only, radiofrequency ablation (RFA) plus resection or RFA only for colorectal liver metastases.
                Thermal destruction techniques, particularly RFA, have been rapidly accepted into surgical practice in the last 5 years. Long-term survival data following treatment of colorectal liver metastasis using RFA with or without hepatic resection are lacking.
                Data from 358 consecutive patients with colorectal liver metastases treated for cure with hepatic resection +/- RFA and 70 patients found at laparotomy to have liver-only disease but not to be candidates for potentially curative treatment were compared (1992-2002).
                Of 418 patients treated, 190 (45%) underwent resection only, 101 RFA + resection (24%), 57 RFA only (14%), and 70 laparotomy with biopsy only or arterial infusion pump placement ("chemotherapy only," 17%). RFA was used in operative candidates who could not undergo complete resection of disease. Overall recurrence was most common after RFA (84% vs. 64% RFA + resection vs. 52% resection only, P < 0.001). Liver-only recurrence after RFA was fourfold the rate after resection (44% vs. 11% of patients, P < 0.001), and true local recurrence was most common after RFA (9% of patients vs. 5% RFA + resection vs. 2% resection only, P = 0.02). Overall survival rate was highest after resection (58% at 5 years); 4-year survival after resection, RFA + resection and RFA only were 65%, 36%, and 22%, respectively (P < 0.0001). Survival for "unresectable" patients treated with RFA + resection or RFA only was greater than chemotherapy only (P = 0.0017).
                Hepatic resection is the treatment of choice for colorectal liver metastases. RFA alone or in combination with resection for unresectable patients does not provide survival comparable to resection, and provides survival only slightly superior to nonsurgical treatment. We compared outcomes of surgery and radiofrequency thermal ablation (RFA) in patients with metachronous liver metastases.
                Between October 1995 and December 2005, 59 patients underwent hepatic resection and 30 underwent RFA for metachronous liver metastases. Patients with extra-hepatic metastases, those who underwent both types of treatment, and those with synchronous hepatic metastasis were excluded.
                The two groups had similar mean age, sex ratio, comorbid medical conditions, primary disease stage, and frequency of solitary metastases. Preoperative mean serum carcinoembryonic antigen (CEA) level was significantly higher in the RFA group (13.4 ng/mL vs. 7.7 ng/mL; p = 0.02). Mean diameter of hepatic metastases was significantly greater in the resection than in the RFA group (3.1 cm vs. 2.0 cm; p = 0.001). Recurrence after treatment of metastasis was observed in 18 of 30 (60.0%) RFA and 33 of 59 (56%) resection patients. Local recurrence at the RFA site was observed in 7 of 30 (23%) patients. Time to recurrence (15 vs. 8 months, p = 0.02) and overall survival (56 vs. 36 months, p = 0.005) were significantly longer in the resection than in the RFA group. In the 69 patients with solitary metastases of diameter </=3 cm, time to recurrence (p = 0.004) and overall survival were significantly greater in the resection group.
                Compared with hepatic resection, RFA for metachronous hepatic metastases from colorectal cancer was associated with higher local recurrence and shorter recurrence-free and overall survival rates, even in patients with solitary, small (</=3 cm) lesions. Hepatic resection (HR) and radiofrequency ablation (RFA) have been proposed as equivalent treatments for colorectal liver metastasis.
                Recurrence patterns after HR and RFA for solitary liver metastasis are similar.
                Analysis of a prospective database at a tertiary care center with systematic review of follow-up imaging in all of the patients.
                Patients with solitary liver metastasis as the first site of metastasis treated for cure by HR or RFA were studied (patients received no prior liver-directed therapy). Prognostic factors, recurrence patterns, and survival rates were analyzed.
                Of the 180 patients who were studied, 150 underwent HR and 30 underwent RFA. Radiofrequency ablation was used when resection would leave an inadequate liver remnant (20 patients) or comorbidity precluded safe HR (10 patients). Tumor size and treatment determined recurrence and survival. The local recurrence (LR) rate was markedly lower after HR (5%) than after RFA (37%) (P<.001). Treatment by HR was associated with longer 5-year survival rates than RFA, including LR-free (92% vs 60%, respectively; P<.001), disease-free (50% vs 0%, respectively; P = .001), and overall (71% vs 27%, respectively; P<.001) survival rates. In the subset with tumors 3 cm or larger (n = 79), LR occurred more frequently following RFA (31%) than after HR (3%) (P = .001), with a 5-year LR-free survival rate of 66% after RFA vs 97% after HR (P<.001). Patients with small tumors experienced longer 5-year overall survival rates after HR (72%) as compared with RFA (18%) (P = .006).
                The survival rate following HR of solitary colorectal liver metastasis exceeds 70% at 5 years. Radiofrequency ablation for solitary metastasis is associated with a markedly higher LR rate and shorter recurrence-free and overall survival rates compared with HR, even when small lesions (< or = 3 cm) are considered. Every method should be considered to achieve resection of solitary colorectal liver metastasis, including referral to a specialty center, extended hepatectomy, and chemotherapy. Hepatic resection is the mainstay of treatment for solitary colorectal liver metastases (mCRC); however, some patients are not ideal candidates. The aim of this study was to compare outcomes for patients with solitary mCRC who underwent resection or ablation.
                A retrospective review of a hepatobiliary database identified patients with solitary mCRC. Patients who were treated with hepatectomy were compared to patients who underwent thermal ablation.
                The median follow-up time was 25.9 months. Ninety-four patients (67.1%) underwent resection whereas 46 patients (32.8%) underwent ablation. Of the resected patients, most (60%) required a major hepatectomy. Tumor ablation was a significant predictor of overall survival (p = 0.002, OR 3.75, 95% CI 1.696-8.284). Overall, the median disease-free survival was 55.2 months for patients undergoing resection vs. 42.6 months for ablated patients (p = 0.073). Median overall survival was 112.7 months for patients undergoing resection vs. 50.2 months for patients undergoing ablation (p = 0.005).
                Patients with solitary hepatic colorectal cancer metastases should be considered for hepatic resection as this provides superior survival when compared to thermal ablation. Although radiofrequency ablation (RFA) is increasingly an accepted option for patients with colorectal liver metastases, patients treated with resection vs RFA may have different tumor biology profiles, which might confound the relationship between choice of liver-directed therapy and outcome.
                Retrospective review of a prospectively collected database.
                Major hepatobiliary center.
                Between January 1, 1999, and August 30, 2006, 258 patients with colorectal liver metastases underwent hepatic resection with or without RFA.
                Evaluation of outcome following resection alone, combined resection-RFA, and RFA alone using 3 statistical methods (paired-match control, Cox proportional hazards multivariate model, and propensity index) to identify and adjust for potential confounding variables.
                The median number of hepatic lesions was 2, and the median size of the largest lesion was 3.0 cm. One hundred ninety-two patients (74.4%) underwent resection alone, 55 patients (21.3%) underwent resection-RFA, and 11 patients (4.3%) underwent RFA alone. Patients who underwent resection-RFA had significantly increased risk of extrahepatic failure at 1 year vs patients who underwent resection alone or RFA alone (P < .05). On matched control and multivariate analyses, patients who underwent RFA with or without resection had significantly worse disease-free and overall survival than patients who underwent resection alone. Propensity score methods revealed that the aggregate distribution of clinical risk factors for resection-RFA was markedly different from that for resection alone. This suggested a lack of comparability to allow for statistical comparisons in the assessment of causal inferences regarding the efficacy of RFA therapy.
                Although results of matched control and multivariate analyses suggested that RFA with or without resection was associated with worse outcome, propensity score methods revealed that the resection-RFA and resection-alone groups were different with regard to baseline tumor and treatment-related factors, making causal inferences about the efficacy of RFA unreliable. The safety of combined hepatic artery infusion chemotherapy (HAI) and radiofrequency ablation (RFA) for liver metastases has not been assessed. We conducted a study to determine the feasibility of using HAI after RFA for colorectal cancer (CRC) liver metastases.
                Between 1996 and 2001, patients with hepatic metastases from CRC were enrolled onto a prospective study of RFA plus HAI consisting of continuous-infusion floxuridine and bolus fluorouracil. Surgical complications, treatment-related toxicities, and patient outcomes were recorded.
                Fifty patients were treated with RFA and HAI with or without resection. A median of two lesions per patient, with a median greatest diameter of 2.0 cm, were treated with RFA. Postoperative complications, including 1 death, occurred in 11 of 50 patients. Toxicity from HAI was relatively mild. At 20 months' median follow-up, 32% of patients remained disease free. Ten percent of patients had recurrences at the site of RFA, 30% developed new liver metastases, and 48% developed extrahepatic disease.
                RFA of CRC liver metastases followed by HAI is feasible and is associated with acceptable complication and toxicity rates. The high rate of disease recurrence in our patients indicates that novel combinations of regional and systemic therapies are needed to improve patient outcomes. There is scant data in the literature regarding radiofrequency thermal ablation (RFA) versus resection of colorectal liver metastases. The aim of this study is to compare the clinical profile and survival of patients with solitary colorectal liver metastasis undergoing resection versus laparoscopic RFA.
                Between 1996 and 2007, 158 patients underwent RFA (n = 68) and open liver resection (n = 90) of solitary liver metastasis from colorectal cancer. Patients were evaluated in a multidisciplinary fashion and allocated to a treatment type. Data were collected prospectively for the RFA patients and retrospectively for the resection patients.
                Although the groups were matched for age, gender, chemotherapy exposure and tumor size, RFA patients tended to have a higher ASA score and presence of extra-hepatic disease (EHD) at the time of treatment. The main indication for referral to RFA included technical reasons (n = 25), patient comorbidities (n = 24), extra-hepatic disease (n = 10) and patient decision (n = 9). There were no peri-operative mortalities in either group. The complication rate was 2.9% (n = 2) for RFA and 31.1% (n = 28) for resection. The overall Kaplan-Meier median actuarial survival from the date of surgery was 24 months for RFA patients with EHD, 34 months for RFA patients without EHD and 57 months for resection patients (p < 0.0001). The 5-year actual survival was 30% for RFA patients and 40% for resection patients (p = 0.35).
                This study shows that, although patients in both groups had a solitary liver metastasis, other factors including medical comorbidities, technically challenging tumor locations and extra-hepatic disease were different, prompting selection of therapy. With a simultaneous ablation program, higher risk patients have been channeled to RFA, leaving a highly selected group of patients for resection with a very favorable survival. RFA still achieved long-term survival in patients who were otherwise not candidates for resection. Aiming at avoidance of futile surgery, we have tested whether radiofrequency ablation (RFA) may be used as first-line treatment in patients with colorectal metastases (CRLM) occurring within the first year after colorectal surgery.
                Surgical resection is the standard treatment in patients with CRLM. Major retrospective analyses have identified the interval between colorectal surgery and the occurrence of CRLM to be of prognostic importance. So far, it is unknown whether survival of the respective patients is hampered if RFA is used as first-line treatment.
                According to a clinical pathway, we have treated patients with CRLM detected within the first year after colorectal surgery preferentially by RFA (n=28). Resection (n=82) was performed in patients who were deemed not amenable to RFA due to number, size, or location of metastatic lesions. The diameter of lesions differed between the groups. All other characteristics of patients and lesions were comparable. Local recurrence and new hepatic lesions were treated with repeated RFA or surgery whenever possible.
                Local recurrence at the site of ablation or resection occurred in 32% and 4% (P<0.001), new metastases apart from the site of previous treatment in 50% and 34% (P=0.179), and systemic recurrence in 32% and 37% (P=0.820) of the patients after RFA and surgery, respectively. Time to progression was significantly shorter in patients primarily treated with RFA (203 vs. 416 days; P=0.017). After primary treatment, 9 RFA patients and 8 surgery patients were amenable to repeated RFA or repeated surgery resulting in identical rates of disease-free patients and identical 3-year overall survival in both treatment groups: 67% and 60%, respectively; P=0.93.
                Despite striking differences in local tumor recurrence and shorter time to progression, survival in patients with early CRLM does not depend on the mode of primary hepatic treatment. Thermoablation, either cryosurgical ablation (CSA) or radiofrequency ablation (RFA), combined with resection is effective in the treatment of extensive bilobar colorectal metastasis.
                Retrospective analysis of a prospective hepatobiliary surgical database.
                Tertiary care referral center.
                Consecutive patients with colorectal hepatic metastases selected for surgical treatment.
                All patients underwent hepatic resection combined with CSA or RFA.
                Local recurrence rates at ablation sites, overall survival, disease-free survival, and hepatic disease-free survival.
                Between January 1, 1998, and December 31, 2003, 665 patients with colorectal metastases underwent hepatic resection. Of these, 39 (5.9%) had additional intraoperative thermoablative procedures (19 RFA, 20 CSA). There was 1 (3%) postoperative death not directly associated with the ablation, and the total morbidity rate was 41% (16 of 39). No RFA-related complication occurred; however, 3 patients developed an abscess at cryoablation sites. Actuarial 3-year survival was 47% for the entire group, with a median follow-up of 21.1 months (range, 0.5-71.4 months). The median disease-free survival was 12.3 months (range, 8.4-16.2 months). Overall, the local in situ recurrence rate according to number of ablated tumors was 14% for RFA and 12% for CSA. Tumor size correlated directly with recurrence (P = .02) in RFA-treated lesions.
                Ablation combined with hepatic resection is rarely necessary or applicable. However, in selected patients whose tumors were otherwise unresectable, additional use of ablation allows effective clearance of disease. In these patients with extensive bilobar disease, recurrence rates are high, but long-term survival is encouraging and may be improved with aggressive postoperative chemotherapy. Liver resection is the preferred treatment for colorectal liver metastases. About 30 to 40 % of the patients survive for five years after radical resection of liver metastases. In contrast to that, patients who are not fit enough for radical resection of metastases and two are treated by chemotherapy survive only for 18 months on average. The survival of patients with non-resectable liver metastases can be improved by metastases destruction and subsequent chemotherapy. At present, radiofrequency ablation (RFA) is widely used for the destruction of liver tumours.
                In the four-year period (2000-2003), 190 patients with liver metastases of colorectal carcinoma have been operated upon at the 2 (nd) Surgical Department of University Hospital in Olomouc. Radical resection of metastases was carried out in 136 patients (71.5 %), RFA combined with liver resection was performed in 23 patients (12 %) and exclusive RFA of metastases was indicated in 31 patients (16 %). The patients were evaluated for the disease-free survival after one year and the survival rates at 12, 24 and 36 months after operation were determined.
                12 months after the operation no tumour progression was found in 115 patients (85 %) subjected to radical resection of liver metastases, in 16 patients (52 %) after sole RFA of metastases and in 15 individuals (65 %) who underwent liver metastasis resection combined with RFA of the remaining cancer foci. The survival of patients after 12, 24 and 36 months was 124 / 136 (91 %) 103 / 136 (76 %) and 79 / 136 (58 %) in the group of radical metastasis resection; after sole RFA of the metastases and subsequent chemotherapy, the survival at 12, 24 and 36 months amounted to 27 / 31 (87 %), 19 / 31 (61 %) and 8 / 31 (26 %) of the patients; in the group undergoing metastases resection combined with RFA and adjuvant chemotherapy patient survival at 12, 24 and 36 months was as follows: 19 / 23 (83 %), 13 / 23 (57 %), and 7 / 23 (30 %).
                RFA combined with adjuvant chemotherapy considerably extends the survival of patients with liver metastases of colorectal carcinoma compared to chemotherapy alone. However, no difference in survival was found between our patients subjected to RFA of metastases and adjuvant chemotherapy and those patients undergoing resection of liver metastases combined with RFA of unresectable metastases and subsequent chemotherapy. The role of ablation for hepatic colorectal metastases (HCM) continues to evolve as ablation technology changes and systemic chemotherapy improves. Our aim was to evaluate the therapeutic efficacy of radiofrequency ablation (RFA) of HCM compared to surgical resection.
                A retrospective review of our 1,105 patient prospective hepatic database from August 1995 to July 2007 identified 192 patients with only hepatic resection or only ablation for HCM.
                Patients who underwent RFA were similar to resection patients based on a similar Fong score (1.8 vs. 2.1 p = 0.28), presence of extrahepatic disease (15% vs. 9% p = 0.19), mean number of hepatic lesions (2.8 vs. 2.1 p = 0.14), and prior chemotherapy (67% vs. 60% p = 0.33). Median time to recurrence was shorter with ablation than resection (12.2 vs. 31.1 months; p < 0.001). Recurrence at the ablation-resection site was more common with ablation than resection occurring 17% vs. 2% (p < or = 0.001) of the time, respectively. Distant recurrence in the liver was also more common with ablation occurring in 33% of patients vs. 14% for resection (p = 0.002).
                Surgical resection is associated with a lower chance of recurrence and a longer disease-free interval than RFA and should remain the treatment of choice in resectable HCM. Recently some have called for randomized controlled trials comparing RFA to hepatic resection, particularly for patients with only a few small metastases. The objectives were to compare local recurrence and survival following RFA and hepatic resection for colorectal liver metastases. This was a retrospective review of open RFA and hepatic resection for colorectal liver metastases between January 1998 and May 2007. All patients who had RFA were considered to have unresectable disease. 58 patients had hepatic resection and 43 had RFA. A 5-year survival after resection was 43% compared to 23% after RFA. For patients with solitary lesions, a 5-year survival was 48% after resection and 15% after RFA. Sixty percent of patients suffered local recurrences after RFA compared to 7% after hepatic resection. RFA is inferior to resection. The results observed in this study support the consensus that RFA cannot be considered an equivalent procedure to hepatic resection. Liver resection is the treatment of choice for patients with solitary colorectal liver metastases. In recent years, however, radiofrequency ablation has been used increasingly in the treatment of colorectal liver metastases. In the absence of randomized clinical trials, this study aimed to compare outcome in patients with solitary colorectal liver metastases treated by surgery or by radiofrequency ablation.
                Solitary colorectal liver metastases were treated by radiofrequency destruction in 25 patients. The indications were extrahepatic disease in seven, vessel contiguity in nine and co-morbidity in nine patients. Outcome was compared with that of 20 patients who were treated by liver resection for solitary metastases and had no evidence of extrahepatic disease. Most patients in both groups also received systemic chemotherapy.
                Median survival after liver resection was 41 (range 0-97) months with a 3-year survival rate of 55.4 per cent. There was one postoperative death and morbidity was minimal. Median survival after radiofrequency ablation was 37 (range 9-67) months with a 3-year survival rate of 52.6 per cent.
                Survival after resection and radiofrequency ablation of solitary colorectal liver metastases was comparable. The latter is less invasive and requires either an overnight stay or day-case facilities only.
                Copyright 2003 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. The role of the radiofrequency ablation (RFA) in treatment of solitary liver metastasis has not been established yet. Both hepatic resection (HR) and RFA have been used increasingly in the treatment of colorectal liver metastases.
                A systemic review was performed to determine the impact of treatment modality of solitary liver metastasis on recurrence patterns, disease-free survival, and overall survival (OS) rates.
                Solitary liver metastases were treated by HR in 116 patients (75.8%) and 37 patients (24.2%) were treated with RFA. Prognostic factors, recurrence rate, recurrence patterns, and survival rates were analyzed. The cumulative 3-year and 5-year local recurrence free survival rates were markedly higher in the HR group (88.0% and 84.6%) as compared with those in the RFA group [53.3% and 42.6%, respectively (P</=0.001)]. The 5-year OS rate was lower in the RFA group as compared with the HR group without statistical significance (5-year OS, 65.7% in the HR, 48.5% in the RFA group, P=0.227).
                Despite of higher local recurrence rate, RFA may be considered as a therapeutic option for patients who are considered unsuitable for conventional surgical treatment. Randomized prospective controlled trials comparing the therapeutic outcome of RFA and HR are definitely warranted. To evaluate the comparative therapeutic efficacy of radiofrequency ablation (RFA) and hepatic resection for the treatment of colorectal liver metastasis (CRLM).
                Between 1996 and 2008, 177 patients underwent RFA, 278 underwent hepatic resection and 27 underwent combination therapy for CRLM. Comparative analysis of clinical outcomes was performed including number of liver metastases, tumor size, and time of CRLM.
                Based on multivariate analysis, overall survival (OS) correlated with the number of liver metastases and the use of combined chemotherapy (P < 0.001, respectively). Disease-free survival (DFS) also correlated with the number of liver metastases (P < 0.001). In the 226 patients with solitary CRLM < 3 cm, OS and DFS rates did not differ between the RFA group and the resection group (P = 0.962 and P = 0.980). In the 70 patients with solitary CRLM ≥ 3 cm, DFS was significantly lower in the RFA group as compared with the resection group (P = 0.015).
                The results indicate that RFA may be a safe alternative treatment for solitary CRLM less than 3 cm, with outcomes equivalent to those achieved with hepatic resection. A randomized controlled study comparing RFA and resection for patients with single small metastasis would help to determine the most efficient treatment modalities for CRLM. We compared outcomes in patients with solitary colorectal liver metastases treated by either hepatic resection (HR) or radiofrequency ablation (RFA).
                A retrospective analysis from a prospective database was performed on 67 consecutive patients with solitary colorectal liver metastases treated by either HR or RFA.
                Forty-two patients underwent HR and 25 patients underwent RFA. The 5-year overall and local recurrence-free survival rates after HR (50.1% and 89.7%, respectively) were higher than after RFA (25.5% and 69.7%, respectively) (P = .0263 and .028, respectively). In small tumors less than 3 cm (n = 38), the 5-year survival rates between HR and RFA were similar, including overall (56.1% vs 55.4%, P = .451) and local recurrence-free (95.7% vs 85.6%, P = .304) survival rates. On multivariate analysis, tumor size, metastases treatment, and primary node status were significant prognostic factors.
                HR had better outcomes than RFA for recurrence and survival after treatment of solitary colorectal liver metastases. However, in tumors smaller than 3 cm, RFA can be recommended as an alternative treatment to patients who are not candidates for surgery because the liver metastases is poorly located anatomically, the functional hepatic reserve after a resection would be insufficient, the patient's comorbidity inhibits a major surgery, or extrahepatic metastases are present.
This systematic review gathers information from several controlled clinical trials and observational studies which are vulnerable to different types of bias. The imbalance between characteristics of patients in the allocated groups appears to be the main concern. Only one randomised clinical trial (published as an abstract), comparing 60 patients receiving RFA plus CT versus 59 patients receiving CT alone, was identified. This study showed that PFS was significantly higher in the group that received RFA. However, it was not able to provide information on overall survival. In conclusion, evidence from the included studies are insufficient to recommend RFA for a radical oncological treatment of CRLMs.