Risk of tumour seeding after percutaneous radiofrequency ablation for hepatocellular carcinoma

Comparison of the therapeutic outcomes between surgical resection and percutaneous ablation for small hepatocellular carcinoma

There seems to be a consensus in regard to the initial treatment of small hepatocellular carcinomas (HCCs): either percutaneous ablation or liver resection should be selected. Liver resection provides for excellent local control, which is one of the most important factors to be considered in the treatment of HCC. However, percutaneous ablation has the advantage of less invasiveness, which allows for repeated sessions of ablation. However, there has been a longstanding debate on which of the two therapeutic modalities might be superior in individual cases with various tumor-related and liver function factors. Although it is practically difficult to conduct randomized controlled trials (RCTs) to compare these two therapeutic modalities, there have been four RCTs published in English, which we focus on in this review article. We discuss the aforementioned unsolved problem according to the results of these RCTs, in addition to the results of a large-scale cohort study and the recommendations of clinical practice guidelines.

First-line radiofrequency ablation with or without artificial ascites for hepatocellular carcinomas in a subcapsular location: local control rate and risk of peritoneal seeding at long-term follow-up

AIM

To compare the long-term local control of hepatocellular carcinoma (HCC) and risk of peritoneal seeding via percutaneous radiofrequency ablation (RFA) using artificial ascites with those of RFA without artificial ascites.

MATERIALS AND METHODS

The Institutional Review Board approved this retrospective study. From April 2005 to February 2008, 160 patients (121 men, 39 women; age range 36-79 years) with a single subcapsular HCC (mean size 2.19 cm) were treated with ultrasonography-guided percutaneous RFA as a first-line therapy. Forty-four patients were treated with RFA using artificial ascites, whereas the other 116 patients were treated without artificial ascites. The cumulative local tumour progression (LTP) and peritoneal seeding were compared in both groups using follow-up computed tomography (CT). Cumulative LTP rates were analysed using the Kaplan-Meier method and the log-rank test. Risk of peritoneal seeding was investigated by means of multivariate analysis.

RESULTS

The overall median follow-up period was 52.5 months (range 13-76 months). The 1, 2, 4, and 6 year cumulative LTP rates were 17.1, 27.6, 35.2, and 35.2%, respectively, in the group with artificial ascites, and 8, 15.2, 26.6, and 34.4% in the group without artificial ascites, without significant difference (p = 0.332). The rates of peritoneal seeding were 6.8% (3/44) in the group with artificial ascites and 2.6% (3/116) in the group without artificial ascites, a non-significant difference (p = 0.347). The biopsy prior to RFA was the independent risk factor of peritoneal seeding regardless of the use of artificial ascites.

CONCLUSION

Long-term local tumour control and risk of peritoneal seeding were comparable for RFA with or without artificial ascites when used as a first-line therapy for subcapsular HCC.

Simultaneous resection of disseminated hepatocellular carcinoma and colon cancer

A 75-year-old woman with abdominal pain and vomiting was admitted to our hospital. Colonoscopy showed an advanced colon cancer that encompassed the entire circumference of the descending colon's lumen. The patient was diagnosed with occlusive ileus associated with the colon cancer. She had been watched for liver cirrhosis due to the hepatitis C virus and received radiofrequency ablation therapy for hepatocellular carcinoma (HCC) 6 years previously. Although she exhibited a gradual increase in serum levels of α-fetoprotein and PIVKA-II starting 2 years before admission, no tumors were detected in the liver by abdominal ultrasonography and computed tomography. On admission, contrast-enhanced computed tomography revealed not only the colon cancer but also a tumor adjacent to the cecum. Both tumors were successfully removed by surgery and a pathological analysis revealed that the cecum tumor was poorly-differentiated HCC. The serum levels of α-fetoprotein and PIVKA-II declined markedly after the operation and no masses considered as peritoneal metastasis have been detected to date. This is the first report of the simultaneous resection of disseminated HCC and colon cancer.

Effectiveness, safety, and local progression after percutaneous laser ablation for hepatocellular carcinoma nodules up to 4 cm are not affected by tumor location

OBJECTIVE

A high-risk location--defined as the tumor margin being less than 5 mm from large vessels or vital structures--represents a well-known limitation and contraindication for radiofrequency ablation of hepatocellular carcinoma (HCC) nodules. The aim of this study was to verify whether HCC nodule location negatively affected the outcome of percutaneous laser ablation in terms of its primary effectiveness, safety, and ability to prevent local tumor progression.

MATERIALS AND METHODS

The medical records and radiologic examinations of 164 cirrhotic patients (90 men, 74 women; mean age ± SD, 68.6 ± 8.3 years) with 182 HCC nodules 4 cm or smaller (mean diameter ± SD, 2.7 ± 0.78 cm) that had been treated by laser ablation between 1996 and 2008 were retrospectively analyzed. One hundred six patients had 116 nodules in high-risk sites (high-risk group), whereas 58 patients had 66 tumors located elsewhere (standard-risk group).

RESULTS

The overall median follow-up was 81 months (range, 6-144 months). The initial complete ablation rate per nodule did not significantly differ between the high-risk group and the standard-risk group (92.2% vs 95.5%, respectively; p = 0.2711). Rates of major complications (high-risk group vs standard-risk group, 1.9% [including one death] vs 0%) and minor complications (5.6% vs 1.0%) were not statistically different between the two groups. Only side effects were recorded significantly more often in high-risk patients than in standard-risk patients (31.5% vs 19.8%; p = 0.049). There was no significant difference in either cumulative incidence of local tumor progression (p = 0.499) or local tumor progression-free survival (p = 0.499, log rank test) between the high-risk group and the standard-risk group.

CONCLUSION

When laser ablation is used to treat small HCC nodules, tumor location does not have a significant negative impact on the technique's primary effectiveness or safety or on its ability to achieve local control of disease.

Salvage hepatectomy for local recurrent hepatocellular carcinoma after ablation therapy

BACKGROUND

The results of salvage hepatectomy for local recurrent hepatocellular carcinoma after incomplete percutaneous ablation therapy are still unclear.

METHODS

We conducted a retrospective analysis of 197 consecutive patients with hepatocellular carcinoma who underwent either salvage hepatectomy after prior incomplete percutaneous ablation therapy (salvage group; n=23) or primary hepatectomy as the initial treatment (primary group; n=174). The two groups were compared with respect to intraoperative data, operative mortality and morbidity, and long-term survival.

RESULTS

The salvage group showed a significantly longer operation time (385 vs. 300 min; P=0.006) and a significantly greater intraoperative blood loss volume (402 vs. 265 ml; P=0.024). The postoperative mortality rate was zero in both groups, and the morbidity rates were similar. Although the 1-, 3-, and 5-year disease-free survival rates after hepatectomy were significantly worse in the salvage group than in the primary group (65%, 41%, and 33% vs. 81%, 51%, and 45%, respectively; P=0.031), the overall survival rates after hepatectomy did not differ significantly (91%, 91%, and 67% vs. 96%, 79%, and 65%, respectively; P=0.790). The 1-, 3-, and 5-year overall survival and disease-free survival rates after percutaneous ablation therapy were also not different from those in the primary group (100, 96, and 83%, P=0.115; and 96, 60, and 45%, P=0.524, respectively).

CONCLUSIONS

The short-term and long-term results of salvage hepatectomy after incomplete percutaneous ablation therapy are equivalent to those of primary hepatectomy. Salvage hepatectomy is an acceptable treatment for patients with local recurrence of hepatocellular carcinoma after ablation therapy.

Complications of radiofrequency ablation of hepatic, pulmonary, and renal neoplasms

Percutaneous thermal ablation has emerged as a viable technique for treatment of numerous solid organ malignancies. As the number of these procedures increases, so do the complications that are seen. Most common complications are generally related to bleeding from the target organ during or after the procedure and from thermal injury to adjacent structures. The nature of these injuries depends on the particular organ being treated, therefore it it best to categorize them this way. We will review the more common complications seen following the ablation of tumors in the liver, kidney, and lung, discuss the clinical presentation associated with each, and suggest precautions to help avoid them in the future. Understanding the potential risks associated with this procedure is critical for treatment planning and fundamental for performing these procedures safely.

Long-term outcome of radiofrequency thermal ablation (RFA) of liver metastases from colorectal cancer (CRC): size as the leading prognostic factor for survival

PURPOSE

The aim of this study was to review some prognostic factors for survival after radiofrequency ablation (RFA) of metastases from colorectal cancer (CRC).

MATERIALS AND METHODS

From 1996 to 2009, 262 patients with metastases from CRC were treated with RFA. Fourteen were lost to follow-up. The following predictors were analysed in the remaining 248: synchronous/metachronous metastases, single/multiple metastases, diameter of largest metastasis and absence/presence of extrahepatic metastases. Survival was measured from the date of metastasis diagnosis and from the date of RFA.

RESULTS

Survival at 1, 2, 3 and 5 years was 93%, 78%, 62% and 35% from metastasis diagnosis, and 84%, 59%, 43% and 23% from the date of RFA. Median survival was 41 months in patients with largest metastasis ≤3 cm and 21.7 months for those with metastases >3 cm (p=0.0001); survival increased to 45.2 months in patients with largest metastasis ≤2.5 cm and fell to 18.5 months in those with metastasis >3.5 cm. Median survival of patients with extrahepatic metastases was significantly lower than that of patients without extrahepatic disease (23.3 vs. 32.6 months, p=0.018).

CONCLUSIONS

In light of our long-term results obtained with commonly used equipment, small lesion size (diameter of largest lesion ≤3 or 2.5 cm) proved to be the most favourable prognostic factor for survival in patients with CRC metastases to the liver treated with RFA. This conclusion is probably related to the possibility of obtaining radical ablation and points to the usefulness of devices allowing ablation of larger volumes. In the presence of extrahepatic metastases, RFA has less impact on survival, even though it is potentially useful in patients at a higher risk of death due to hepatic rather than extrahepatic metastases.

Radiofrequency ablation or percutaneous ethanol injection for the treatment of liver tumors

The liver is a common location of both primary and secondary malignancies. For unresectable liver cancer, many local ablative therapies have been developed. These include e.g., percutaneous ethanol injection (PEI), percutaneous acetic acid injection, radiofrequency ablation (RFA), cryoablation, microwave ablation, laser-induced thermotherapy, and high-intensity focused ultrasound. RFA has recently gained interest and is the most widely applied thermoablative technique. RFA allows more effective tumor control in fewer treatment sessions compared with PEI, but with a higher rate of complications. However, there are certain circumstances where PEI therapy represents a better strategy to control liver tumors than RFA, especially in situations where RFA is difficult, for example when large vessels surround the tumor. In the context of hepatocellular carcinoma (HCC), both RFA and PEI are feasible and of benefit in non-operable patients. RFA seems superior to PEI in HCC > 2 cm, and the combination of interventions may be of benefit in selected patients. Liver resection is superior to RFA for patients with HCC meeting the Milan criteria, but RFA can be employed in tumors ≤ 3 cm and where there is an increased expected operative mortality. In addition, some lines of evidence indicate that RFA and PEI can be employed as a bridge to liver transplantation. The use of RFA in colorectal liver metastases is currently limited to unresectable disease and for patients unfit for surgery. The aim of this article is to summarize the current status of RFA in the management of liver tumors and compare it to the cheap and readily available technique of PEI.

Mortality and complication rates of percutaneous ablative techniques for the treatment of liver tumors: a systematic review

OBJECTIVES

Reported rates of major complications and mortality of radiofrequency ablation (RFA), microwave ablation (MWA) and percutaneous ethanol injection (PEI) for the treatment of liver tumours were substantially heterogeneous among studies. The aim was to analyse the mortality and major complication rates of percutaneous RFA, PEI and MWA.

METHODS

MEDLINE and EMBASE search from January 1982 to August 2010. Randomised clinical trials and observational studies, age >18, more than 50 patients for each technique analysed, studies reporting mortality and major complications were included. Random effects model was performed, with assessment for heterogeneity and publication bias.

RESULTS

Thirty-four studies including 9531, 1185, and 1442 patients for RFA, MWA, and PEI, respectively were included. For all ablative techniques pooled proportion mortality rate was 0.16% (95% confidence interval [CI], 0.10-0.24). Pooled mortality rate associated with RFA, PEI and MWA was 0.15% (0.08-0.23), 0.59% (0.14-1.3) and 0.23% (0.0-0.58) respectively. Pooled proportion of major complications was 3.29% (2.43-4.28). Major complication rates associated with RFA, MWA, and PEI was 4.1% (3.3-5.1), 4.6% (0.7-11.8) and 2.7% (0.28-7.4) respectively.

CONCLUSIONS

Percutaneous RFA, PEI and MWA can be considered safe techniques for the treatment of liver tumours.

Clinical features and risk factors of extrahepatic seeding after percutaneous radiofrequency ablation for hepatocellular carcinoma

AIM

  To clarify the clinical features of and risk factors for extrahepatic seeding, a major complication following radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC).

METHODS

  Our prospective database of 351 nodules in 257 patients with HCC who had undergone RFA between April 2001 and April 2008 was reviewed. The following variables were assessed to identify the risk factors for extrahepatic seeding: age, sex, viral markers, Child-Pugh class, tumor size, number of tumors, RFA indication (tumor size ≤3 cm, number of tumors ≤3), tumor biopsy prior to RFA, degree of histological differentiation, tumor markers, tumor location, number of sessions, and combined transcatheter arterial chemoembolization.

RESULTS

  The median follow-up period was 36.5 months, during which the rate of seeding after was 5.1% and the 5-year cumulative seeding rate was 8.4%. The survival rate after neoplastic seeding was 21% at 5 years. Univariate analysis of the risk factors for neoplastic seeding showed significant differences in tumor size, RFA indication, subcapsular lesion, number of sessions, tumor biopsy prior to RFA, and des-gamma-carboxy prothrombin value. However, multivariate analysis showed that the only independent risk factor was RFA indication.

CONCLUSIONS

  The prognosis of patients with neoplastic seeding was poor. In particular, RFA performed for HCC not satisfying the RFA indication showed a high risk of seeding, and careful consideration should be given to the optimal treatment method and avoiding direct puncture of subcapsular tumors.

Current status of therapy for hepatocellular carcinoma

The incidence of hepatocellular carcinoma (HCC) is increasing worldwide. A multi-disciplinary approach is required for its management. Screening high-risk patients allows for earlier diagnosis and the use of potentially curative therapies. Current recommendations for HCC screening for patients with cirrhosis are an abdominal ultrasound and serum alpha fetoprotein level every 6 to 12 months. Treatment choice depends on tumor stage, liver function and the patient's overall functional status. Curative therapies include surgical resection, liver transplantation (LT), transarterial chemoembolization, and radiofrequency ablation (RFA). Surgical resection, either primary resection or LT, is the treatment most likely to result in cure of HCC. Which option to pursue is based on multiple factors. LT has the potential benefit of treating both HCC and the underlying cirrhosis; however, long wait times incur the risk of tumor progression. Firm recommendations regarding the role of living donor LT for HCC are not yet possible because of conflicting data. HCC recurrence after LT is 8-11% and several adjuvant therapies have been investigated to reduce this. Bridging therapy and tumor downsizing are techniques that also may be considered to deal with long waiting periods and qualification for LT, respectively. If neither LT nor primary resection is possible, loco-regional therapies such as RFA and TACE should be considered. Systemic chemotherapies have proved disappointing for the treatment of HCC; however, newer targeted therapies such as sorafenib and cetuximab have provided new hope for the future.

Complications of radiofrequency ablation of neoplasms

Radiofrequency ablation (RFA) is one of several techniques currently available to the interventional radiologist for direct local destruction of neoplastic tissue. At the present time RFA is among the most widely used and investigated of local therapies and has shown promise in oncological therapy for a variety of tissue types and anatomic locations, the latter including liver, kidney, bone, lung, and adrenal gland. This review will discuss risks of RFA, including methods to anticipate, avoid, ameliorate, or treat complications that may occur as a result of RFA.

Test-retest repeatability of MR elastography for noninvasive liver fibrosis assessment in hepatitis C

PURPOSE

To conduct a rigorous evaluation of the repeatability of liver stiffness assessed by MR elastography (MRE) in healthy and hepatitis-C-infected subjects.

MATERIALS AND METHODS

A biopsy-correlated repeatability study using four-slice MRE was conducted in five healthy and four HCV-infected subjects. Subjects were scanned twice on day 1 and after 7-14 days. Each slice was acquired during a 14-s breath-hold with a commercially available acquisition technique (MR-Touch, GE Healthcare). Results were analyzed by two independent analysts.

RESULTS

The intraclass correlation coefficient (ICC) was 0.85 (90% confidence interval [CI]: 0.71 to 0.98) for the between-scan average of maximum stiffness within each slice and 0.88 (90% CI: 0.78 to 0.99) for the average of mean stiffness within each slice for the primary analyst. For both analysts, the average of the mean liver stiffness within each slice was highly reproducible with ICC of 0.93 and 0.94. Within-subject coefficients of variation ranged from 6.07% to 10.78% for HCV+ and healthy subjects.

CONCLUSION

MRE is a highly reproducible modality for assessing liver stiffness in HCV patients and healthy subjects and can discriminate between moderate fibrosis and healthy liver. MRE is a promising modality for noninvasive assessment of liver fibrosis (CLINICALTRIALS.GOV IDENTIFIER: NCT00896233).

Radiofrequency ablation of hepatocellular carcinoma

Radiofrequency ablation (RFA), usually performed under percutaneous ultrasound guidance, is considered the gold standard among minimally invasive therapies. On the strength of some recent randomized trials, its indications include operable patients with small hepatocellular carcinoma and inoperable patients with more advanced disease also in combination with other therapies. RFA has lower complication rates and costs less than surgery.

Radiofrequency ablation of colorectal hepatic metastases

Radiofrequency ablation (RFA) may be performed intraoperatively, laparoscopically, or percutaneously. The percutaneous approach is associated with the least procedural risk and may be performed under local anesthesia. Percutaneous RFA should be considered a primary treatment option for patients with unresectable hepatic tumors or conditions that prohibit general anesthesia or abdominal surgery. Continually improving thermal ablation and imaging technologies are likely to further increase tumor ablation efficacy and expand its role in treatment of hepatic metastases.

Recent advances of radiofrequency ablation for early hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the third leading cause of death in the malignant neoplastic diseases in the world. Surgical operation is sometimes not indicated because of complicated liver cirrhosis and extrahepatic disorders. Radiofrequency ablation has been developed as a less invasive treatment for HCC since 1999, and long-term outcome has been shown. There are several complications which should be paid attention, and to improve the prognosis, combination treatment with transarterial chemoembolization should be discussed. Overall survival after between RFA and surgical resection should be compared prospectively. Establishment of staging system for treatment allocation of HCC and prevention of HCC recurrence is important issue to be examined.

Ultrasound-guided high-intensity focused ultrasound treatment for needle-track seeding of hepatocellular carcinoma: preliminary results

PURPOSE

To evaluate therapeutic efficacy of ultrasound (US)-guided high-intensity focused ultrasound (HIFU) ablation for treatment of needle-track seeding of hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Nine patients with needle-track seeding of HCC were treated as outpatients using US-guided HIFU ablation. The mean size of the lesion was 1.8 cm (range 1.1 to 2.6 cm), two lesions were located on the abdominal wall, seven lesions were located on the chest wall. An acoustic power of 200 to 400 W was used determined by the echo changes after energy exposures, intermittent HIFU exposures of 1 to 2 s were used during treatment. Treatment was considered complete when the entire nodule and a surrounding 0.5 cm margin become hyperechoic on US. The outcome of HIFU ablation was observed by US and contrast-enhanced magnetic resonance imaging during follow up.

RESULTS

HIFU ablation was performed smoothly in all patients, the treatment lasted for 6 to 21 min (mean 12 min). No major complications occurred. During a mean follow up of 10.3 months (range 7-15 months), persistent absence of lesion enhancement was seen in eight patients, one patient developed a recurrent lesion near the treated area, which was successfully treated by a repeat HIFU ablation.

CONCLUSIONS

US-guided HIFU ablation may be an effective treatment for needle-track seeding of HCC.

Radiofrequency ablation as first-line treatment for small solitary hepatocellular carcinoma: long-term results

AIMS

To evaluate long-term results of patients with small solitary hepatocellular carcinoma (HCC) and well-preserved liver function who received radiofrequency ablation (RFA) as first-line treatment.

MATERIALS AND METHODS

Between November 1999 and June 2007, 247 patients with solitary HCC ≤5 cm and liver status scored as Child-Pugh class A were enrolled. RFA was performed in 224 patients as first-line treatment; 23 patients excluded from RFA because of unfavorable tumor location or their unwillingness, and all of these patients converted to surgical resection.

RESULTS

In the 224 patients treated with RFA, the overall 5-, 7-, 10-year survival rates were 59.8%, 55.2%, 33.9%, respectively, and the median of overall survival was 76.1 months. Complete ablation was achieved in 216 patients (96.4%). Major complications occurred in two patients (0.9%), with no treatment-related death or needle track seeding. Indocyanine green retention rate in 15 min (ICGR15) (P = 0.014) and prothrombin activity (P = 0.004) were associated with overall survival. A subgroup of patients with ICGR15 ≤ 10% and prothrombin activity >75% had 5-, 7-, 10-year survival rates of 67.1%, 64.2%, 57.1%, respectively, with a median survival of 87.7 months. The 10-year recurrence-free, tumor-free survival rates were 17.5%, 28.2%, respectively. Serum albumin was the only factor that significantly impacted recurrence-free and tumor-free survival (P = 0.008, 0.002, respectively).

CONCLUSION

RFA is considered to be the treatment of first choice for patients with solitary HCC ≤5 cm and well-preserved liver function. Surgery can be used as second-line therapy for few patients if RFA is unfeasible.

Minimally invasive image-guided therapy for inoperable hepatocellular carcinoma: What is the evidence today?

Hepatocellular carcinoma (HCC) is a primary malignant tumor of the liver that accounts for an important health problem worldwide. Only 10-15% of HCC patients are suitable candidates for hepatic resection and liver transplantation due to the advanced stage of the disease at time of diagnosis and shortage of donors. Therefore, several minimally invasive image-guided therapies for locoregional treatment have been developed. Tumor ablative techniques are either based on thermal tumor destruction, as in radiofrequency ablation, cryoablation, microwave ablation, laser ablation and high-intensity focused ultrasound, or chemical tumor destruction, as in percutaneous ethanol injection. Image-guided catheter-based techniques rely on intra-arterial delivery of embolic, chemoembolic or radioembolic agents. These minimally invasive image-guided therapies have revolutionized the management of inoperable HCC. This review provides a description of all minimally invasive image-guided therapies currently available, an up-to-date overview of the scientific evidence for their clinical use, and thoughts for future directions.

Hepatic resection versus radiofrequency ablation for very early stage hepatocellular carcinoma: a Markov model analysis

No adequate randomized trials have been reported for a comparison between hepatic resection (HR) versus radiofrequency ablation (RFA) for the treatment of patients with very early stage hepatocellular carcinoma (HCC), defined as an asymptomatic solitary HCC <2 cm. For compensated cirrhotic patients with very early stage HCC, a Markov model was created to simulate a randomized trial between HR (group I) versus primary percutaneous RFA followed by HR for cases of initial local failure (group II) versus percutaneous RFA monotherapy (group III); each arm was allocated with a hypothetical cohort of 10,000 patients. The primary endpoint was overall survival. The estimates of the variables were extracted from published articles after a systematic review. In the parameter estimations, we assumed the best scenario for HR and the worst scenario for RFA. The mean expected survival was 7.577 years, 7.564 years, and 7.356 years for group I, group II, and group III, respectively. One-way sensitivity analysis demonstrated that group II was the preferred strategy if the perioperative mortality rate was greater than 1.0%, if the probability of local recurrence following an initial complete ablation was <1.9% or if the positive microscopic resection margin rate was >0.3%. The 95% confidence intervals for the difference in overall survival were -0.18-0.18 years between group I and II, 0.06-0.36 years between group I and III, and 0.13-0.30 years between group II and III, respectively.

CONCLUSION

Primary percutaneous RFA followed by HR for cases of initial local failure was nearly identical to HR for the overall survival of compensated cirrhotic patients with very early stage HCC.

A trucut biopsy needle for bipolar radiofrequency ablation of needle tract: a proof-of-concept experiment

OBJECTIVE

To develop a trucut biopsy needle featuring two electrodes that allow for bipolar radiofrequency (RF) coagulation of the puncture tract.

METHODS

We modified a 14-G trucut biopsy needle to contain two insulated electrodes and connected the device to an RF generator. Biopsies in ex vivo porcine liver and kidney were performed. The puncture tract was coagulated by using different RF energy settings (5 W, 10 W, 20 W). Tissue specimens were dissected along the puncture tract and the coagulation area was macroscopically evaluated. CT-guided in vivo liver and kidney biopsies were performed in two domestic pigs. Lengths of specimens were measured. Post-biopsy contrast-enhanced CT examinations were performed to rule out biopsy-related bleeding. Animals were euthanised and coagulation areas macroscopically explored.

RESULTS

The mean diameters of the coagulated area around the ex vivo biopsy tract were 4.2 +/- 1.1 mm (5 W), 6.0 +/- 2.0 mm (10 W) and 5.2 +/- 0.51 mm (20 W) in liver and 5.0 +/- 0.7 mm (5 W), 6.6 +/- 0.9 (10 W) and 6.0 +/- 2.0 mm (20 W) in kidney. After biopsies CT revealed no bleeding. Mean maximum coagulation diameters were 10.1 +/- 4.6 mm (10 W) in liver and 6.0 +/- 2.5 mm (10 W) in kidney. Mean length of the specimens was 12.2 +/- 4.4 mm in kidney and 11.1 +/- 3.6 mm in liver tissue.

CONCLUSION

Bipolar RF biopsy is a promising tool for tract coagulation after percutaneous biopsy.

Single HCC between 2 and 5 cm: the grey zone: surgeon's perspective

In the treatment of hepatocellular carcinoma (HCC), control of the tumor itself, vascular invasion, and minute intrahepatic metastases is the main important factor to be considered. Based on previously reported indirect evidence, liver resection would seem to have advantages over percutaneous ablation for single HCCs measuring between 2 and 5 cm in diameter. In conclusion, liver function permitting, resection would be the therapeutic option of first choice. In cases with poor liver functional reserve, liver transplantation would be a good therapeutic option, depending on the age of the patient.

Radiofrequency ablation of hepatocellular carcinoma: long-term results and prognostic factors in 235 Western patients with cirrhosis

For the treatment of small hepatocellular carcinoma (HCC), radiofrequency ablation (RFA) is in some centers considered a first-line therapeutic option. However, such a strategy is still under debate with regard to tumor and patient characteristics. In this single-center study we assessed the 5-year survival and prognosis factors in 235 consecutive patients with cirrhosis (Child-Pugh A/B: 205/30) who received RFA as first-line treatment for up to three HCC <or=5 cm (307 tumors; mean diameter: 29 +/- 10 mm; 53 multinodular forms). Among these patients, 67 satisfied the criteria for resection according to the Barcelona Clinic Liver Cancer. Complete ablation was obtained in 222 patients (94%). Overall, 337 RFA sessions were performed including iterative RFA for recurrence. Major complications occurred in three patients (0.9%), including one treatment-related death. After 27 +/- 20 months of mean follow-up, local or distant, or both, tumor recurrence occurred in 16, 88, and 11 patients, respectively. Twenty-nine patients underwent transplantation and were removed from the study at this point. Overall 5-year, recurrence-free, and tumor-free (including results of iterative RFA) survival rates were, respectively, 40%, 17%, and 32%. The overall 5-year survival rate was 76% for operable patients. Factors associated with overall survival were prothrombin activity (hazard ratio [HR] = 0.97, 0.96-0.98; P < 0.0001) and serum levels of alpha-fetoprotein (AFP) (HR = 1.02, 1.02-1.02; P < 0.0001), and factors associated with tumor recurrence were multinodular forms (HR = 2.34; 1.52-3.6; P = 0.0001) and serum AFP levels (HR = 1.015, 1.014-1.016; P = 0.015). Tumor size was associated with local recurrence but not with overall and tumor-free survival.

CONCLUSION

RFA is a safe and effective first-line treatment of HCC up to 5 cm in diameter, especially for patients with a single tumor, a low serum AFP level, and well-preserved liver function.

Needle track seeding following percutaneous procedures for hepatocellular carcinoma

Neoplastic seeding may arise after diagnostic or therapeutic percutaneous procedures for hepatocellular carcinoma. The true incidence of seeding with hepatocellular carcinoma is difficult to assess precisely, but a significant risk of seeding exists and is greater when performing diagnostic biopsy as compared to therapeutic percutaneous procedures [radiofrequency ablation, radiofrequency ablation (RFA); percutaneous ethanol injection, Percutaneous ethanol injection (PEI)]. Whenever liver transplantation is feasible, diagnostic needle biopsies should be avoided, but RFA and PEI are often needed as "bridge" treatments. The role of adjuvant treatments in reducing the incidence of seeding following RFA or PEI requires further evaluation.

Society of Interventional Radiology position statement on percutaneous radiofrequency ablation for the treatment of liver tumors

Focal tumor ablation--whether applied percutanously, laparoscopically, or by means of open surgery--is an effective therapy for selected liver tumors. The choice of liver ablation as well as the choice between percutaneous and surgical approaches is dependent on tumor factors, patient factors, and other viable treatment options. Currently, the largest cumulative reported experience is with radiofrequency (RF) ablation of hepatocellular carcinoma and colorectal metastases. This document is a position statement of the Interventional Oncology Task Force and the Standards Division of the Society of Interventional Radiology regarding the use of percutaneous RF ablation for the treatment of liver tumors.

Preoperative prediction of poorly differentiated components in small-sized hepatocellular carcinoma for safe local ablation therapy

BACKGROUND

Poorly differentiated hepatocellular carcinoma (HCC) has a malignant potential such as frequent microvascular invasion even if the tumor is smaller than 3 cm in diameter. The aim of this study was to clarify the preoperative predictors of poorly differentiated HCC for safe local ablation therapy.

METHODS

Sixty-six patients underwent a hepatic resection for solitary small-sized HCC (<or=3 cm) were included in this study. According to the postoperative histological examination, the patients were divided into a "poorly differentiated group" (n = 17) and a "well/moderately differentiated group" (n = 49). This study investigated the clinicopathological factors and imaging findings, and elucidated the predictive factors of the poorly differentiated type.

RESULTS

In a univariate analysis, serum hepatitis B surface antigen positive, hepatitis C virus antibody negative, alpha-fetoprotein level, des-gamma-carboxy prothrombin level, and a high contrast-to-noise ratio (CNR) in T2-weighted MR imaging were significantly associated with the poorly differentiate type. In a multivariate analysis, a high CNR in T2-weighted MR imaging was the only independent predictor of the poorly differentiated type. In the postoperative pathological findings, portal vein invasion and intrahepatic metastasis were significantly frequent in the poorly differentiated group.

CONCLUSIONS

The CNR in T2-weighted MR imaging is a useful tool to predict poorly differentiated HCC preoperatively.

Major complications after radiofrequency ablation for liver tumors: Analysis of 255 patients

AIM: To investigate the major complications after radiofrequency ablation (RFA) for the treatment of liver tumors and analyze possible risk factors that precipitate these complications.

METHODS: From March 2001 to April 2008, 255 patients with liver tumors (205 male, 50 female; age range, 18-89 years; mean age, 56.0 years) who received RFA were enrolled in this study. Of these patients, 212 had hepatocellular carcinoma, 39 had metastatic liver tumors and four had cholangiocellular carcinoma. One hundred and forty eight patients had a single tumor, and 107 had multiple tumors. Maximum diameter of the tumors ranged 1.3-20 cm (mean, 5.1 cm). All patients were treated with a cooled-tip perfusion electrode attached to a radiofrequency generator (Radionics, Burlington, MA, USA). RFA was performed via the percutaneous approach (n = 257), laparoscopy (n = 7), or open surgical treatment (n = 86). The major complications related to RFA were recorded. The resultant data were analyzed to determine risk factors associated these complications.

RESULTS: Among the 255 patients, 425 liver tumors were treated and 350 RFA sessions were performed. Thirty-seven (10%) major complications were observed which included 13 cases of liver failure, 10 cases of hydrothorax requiring drainage, three cases of tumor seeding, one case of upper gastrointestinal bleeding, one case of intrahepatic abscess, one case of bile duct injury, one case of cardiac arrest, and five cases of hyperglycemia. Seven patients had more than two complications. Liver failure was the most severe complication and was associated with the highest mortality. Eleven patients died due to worsening liver decompensation. Child-Pugh classification (P = 0.001) and choice of approach (P = 0.045) were related to post-treatment liver failure, whereas patient age, tumor size and number were not significant factors precipitating this complication.

CONCLUSION: RFA can be accepted as a relatively safe procedure for the treatment of liver tumors. However, attention should be paid to possible complications even though the incidences of these complications are rare. Careful patient selection and the best approach choice (percutaneous, laparoscopy, or laparotomy) will help to minimize the incidence and morbidity rate of complications which occur after RFA.

Needle track seeding: A real hazard after percutaneous radiofrequency ablation for colorectal liver metastasis

Neoplastic needle track seeding following percutaneous radiofrequency ablation (RFA) of secondary liver tumors is exceedingly rare. Reports on cutaneous tumor seeding after percutaneous RFA for colorectal liver metastasis are even rarer in the literature. Here we report a case of a 46-year-old female who developed an ulcerating skin lesion along the needle track of a previous percutaneous RFA site around 6 mo after the procedure. The previous RFA was performed by the LeVeen^® needle for a secondary liver tumor from a primary rectal cancer. The diagnosis of secondary skin metastasis was confirmed by fine needle aspiration cytology. The lesion was successfully treated with wide local excision. We believe that tumor seeding after percutaneous RFA in our patient was possibly related to its unfavorable subcapsular location and the use of an expansion-type needle. Hence, prophylactic ablation of the needle track should be performed whenever possible. Otherwise, alternative routes of tumor ablation such as laparoscopic or open RFA should be considered.

Long-term outcome of cirrhotic patients with early hepatocellular carcinoma treated with ultrasound-guided percutaneous laser ablation: a retrospective analysis

PURPOSE

Percutaneous laser ablation (PLA) has been proposed as an active treatment in patients with hepatocellular carcinoma (HCC). However, large multicenter studies using this technique have not been reported.

PATIENTS AND METHODS

We retrospectively analyzed treatment and survival parameters of 432 cirrhotic patients with nonsurgical early HCC (single nodule < or = 4 cm or three nodules < or = 3 cm each) who had received PLA in nine Italian centers.

RESULTS

Single tumors were seen in 344 (80%) of 432 patients, and two to three nodules were seen in 88 patients (20%), for a total of 548 tumors. An initial complete response after PLA was observed in 338 patients (78%). Median overall survival time was 47 months (95% CI, 41 to 53 months). The 3- and 5-year cumulative survival rates were 61% and 34%, respectively. In multivariate analysis, independent predictors of survival were serum albumin levels more than 3.5 g/dL (P = .002; risk ratio [RR] = 0.580; 95% CI, 0.409 to 0.821), the achievement of a complete tumor ablation (P = .001; RR = 0.517; 95% CI, 0.346 to 0.771), and age less than 73 years (P < .001; RR = 0.466; 95% CI, 0.320 to 0.681). Child-Turcotte-Pugh class A patients had a 5-year cumulative survival rate of 41%; this figure increased up to 60% with a median survival time of 63 months (95% CI, 48 to 78 months) in patients with tumors < or = 2.0 cm.

CONCLUSION

This analysis confirms that a complete tumor ablation results in improved survival in patients with nonsurgical HCC. Ideal candidates for PLA are younger patients with normal serum albumin levels and tumor size < or = 2 cm.

Muscle metastasis from hepatocellular carcinoma in a patient treated with TACE

The authors describe a rare case of hepatocellular carcinoma that metastasized to the pectineal muscle of the right thigh. The patient had been treated with surgical procedures and with multiple sessions of transarterial chemoembolization, one of which was complicated by a right femoral artery hematoma at the catheter insertion site. It is unclear whether the muscle metastasis was caused by blood-borne spread or by tumor-cell seeding caused by the TACE procedure.

The current role of radiofrequency ablation in the management of hepatocellular carcinoma: a systematic review

OBJECTIVE

To review the current status of radiofrequency ablation (RFA) in the management of hepatocellular carcinoma (HCC).

SUMMARY BACKGROUND DATA

The development of local ablative therapy has been 1 of the major advances in the treatment of HCC. Its role in the management of HCC is still rapidly evolving.

METHODS

Studies were identified by searching Medline, and PubMed databases for articles from January 1997 to April 2008 using the keywords "radiofrequency ablation," "hepatocellular carcinoma" and "ablation of HCC." Additional papers were identified by a manual search of the references from the key articles. Randomized controlled trials, nonrandomized comparative studies, cohort studies, were reviewed. Cohort studies with follow-up of less than 12 months and case reports were excluded.

RESULTS

Five aspects of RFA were analyzed: (1) RFA in comparison with other local ablative therapies; (2) RFA for unresectable HCC; (3) RFA as bridging therapy before liver transplantation; (4) RFA as primary treatment for resectable HCC; and (5) RFA for recurrent HCC after partial hepatectomy. Ten RCTs, 8 nonrandomized controlled trials and 26 cohort studies were included in this analysis.

CONCLUSIONS

The evidence in the medical literature showed RFA was more effective than other local ablative therapies, and supported its use in the treatment of unresectable small HCC, recurrent small HCC, and as bridging therapy before liver transplantation, and as a primary treatment in competition with partial hepatectomy for resectable small HCC.

Neoplastic seeding after radiofrequency ablation for hepatocellular carcinoma

BACKGROUND

Neoplastic seeding reportedly occurs in up to 12.5% of patients treated with radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). The aim of this study is to assess the incidence, risk factors, and prognosis of neoplastic seeding after RFA among a large number of patients with a long-term follow-up.

METHOD

From February 1999 to December 2004, 1,031 patients underwent a total of 1,845 treatments with RFA for a total of 3,837 HCC nodules. The following variables were assessed to elucidate the risk factors of neoplastic seeding: age, sex, positivity for viral markers, tumor size, number of tumor nodules, number of RFA sessions, tumor location, percutaneous biopsy prior to RFA, alpha-fetoprotein (AFP), des-gamma-carboxy prothrombin (DCP) and lens culinaris agglutinin-reactive fraction of AFP (AFP-L3) levels, and the degree of tumor differentiation.

RESULTS

Neoplastic seeding was detected in 33 patients (3.2% per patient) at intervals of 4.8-63.8 (median, 15.2) months after RFA. On multivariate logistic regression analysis, only the poor differentiation degree was associated with the risk of neoplastic seeding (P= 0.012). Of tumor factors, tumor size, and AFP, DCP, and AFP-L3 levels were significantly associated with the poor differentiation degree. The cumulative survival rates 1 and 2 yr after the detection of neoplastic seeding were 86% and 47%, respectively.

CONCLUSION

Poor differentiation degree was the risk factor of neoplastic seeding after RFA for HCC. The surrogate markers for poor differentiation degree were larger tumor size and elevated tumor marker levels. Indication for RFA should be carefully considered for HCC patients under these conditions.

Radiological and pathological assessment of hepatocellular carcinoma response to radiofrequency. A study on removed liver after transplantation

BACKGROUND

The real efficacy of radiofrequency ablation (RFA) in destroying hepatocellular carcinoma is not completely known, nor is the ability of computed tomography (CT) to precisely assess response. Our aims were to analyze pathological response, tumor size influence, and CT response evaluation.

MATERIALS AND METHODS

This was a retrospective study of 30 hepatocellular carcinoma nodules treated by RFA before liver transplant (LT) in 28 patients. Pathological study of the whole removed liver was then performed and the tumor response was classified as complete, incomplete, or absent. The biggest nodule diameter was estimated by CT or ultrasound. The procedure was carried out percutaneously in all but 3 patients, and in those 3 it was done surgically.

RESULTS

The pathological response was complete in 14 nodules (46.7%) and incomplete in 16 (53.3%). The differences in mean preoperative diameter between cases with complete and incomplete response were not significant (p = 0.3). We found that small tumors were not always completely destroyed, whereas bigger tumors could be successfully deleted. There was no clear association between any location and better or poorer response. The detection of RFA incomplete response by means of CT scan had 50% sensitivity and 100% specificity.

CONCLUSIONS

In our experience, RFA can achieve some degree of tumor destruction in every treated case of hepatocellular carcinoma, the complete response rate being slightly lower than half. We have not found any association of response with tumor size or interval RFA-transplant. Second, CT had not enough sensitivity to assess RFA response of hepatocellular carcinoma.

Intrahepatic dissemination of hepatocellular carcinoma after local ablation therapy

BACKGROUND/PURPOSE

We aimed to clarify the histological features of and risk factors for intrahepatic dissemination after local ablation therapy (LAT) for hepatocellular carcinoma (HCC).

METHODS

Between April 1992 and December 2005, 192 HCC patients underwent hepatic resection at our department, among whom were 17 patients who had local recurrences after LAT. Eight of these 17 patients had intrahepatic dissemination. The clinical and histological characteristics of these 8 surgically treated patients with intrahepatic dissemination were investigated.

RESULTS

Histologically, numerous intrahepatic metastases were observed, mainly in the same section as the treated tumor, together with main or sectional portal vein tumor thrombi. Before the ablation therapy, the average tumor diameter was 2.1 cm, and 62.5% of the tumors were adjacent to the main or sectional portal vein. In terms of therapeutic factors, 25% of the patients had a prior needle biopsy and 62.5% had insufficient safety margins.

CONCLUSIONS

LAT for HCCs (even those less than 3 cm in diameter) adjacent less than 5 mm to the main or sectional portal vein possibly promotes intrahepatic dissemination.

Society of Interventional Radiology position statement on percutaneous radiofrequency ablation for the treatment of liver tumors

Focal tumor ablation--whether applied percutanously, laparoscopically, or by means of open surgery-is an effective therapy for selected liver tumors. The choice of liver ablation as well as the choice between percutaneous and surgical approaches is dependent on tumor factors, patient factors, and other viable treatment options. Currently, the largest cumulative reported experience is with radiofrequency (RF) ablation of hepatocellular carcinoma and colorectal metastases. This document is a position statement of the Interventional Oncology Task Force and the Standards Division of the Society of Interventional Radiology regarding the use of percutaneous RF ablation for the treatment of liver tumors.

Radiofrequency ablation versus ethanol injection for early hepatocellular carcinoma: A randomized controlled trial

OBJECTIVE

To compare percutaneous ethanol injection (PEI), the standard approach which has been used for many years to treat early non-surgical hepatocellular carcinoma (HCC) in cirrhotic patients, and radiofrequency ablation (RFA), which has become an interesting alternative.

MATERIAL AND METHODS

A randomized trial was carried out on 139 cirrhotic patients in Child-Pugh classes A/B with 1-3 nodes of HCC (diameter 15-30 mm), for a total of 177 lesions. Patients were randomized to receive RFA (n=70) or PEI (n=69). The primary end-point was complete response (CR) 1 year after the percutaneous ablation of all HCC nodes identified at baseline. Secondary end-points were: early (30-50 days) CR, complications, survival and costs.

RESULTS

In an intention-to-treat analysis, 1-year CR was achieved in 46/70 (65.7%) and in 25/69 (36.2%) patients treated by RFA and PEI, respectively (p=0.0005). For lesions >20 mm in diameter, there was a larger CR rate in the RFA group (68.1% versus 26.3%). An early CR was obtained in 67/70 (95.7%) patients treated by RFA compared with 42/64 (65.6%) patients treated by PEI (p=0.0001). Complications occurred in 10 and 12 patients treated by RFA and PEI, respectively. The overall survival rate was not significantly different in the RFA versus PEI arm (adjusted hazard ratio=0.88, 95% CI: 0.50-1.53). There was an incremental health-care cost of 8286 euro for each additional patient successfully treated by RFA.

CONCLUSIONS

The 1-year CR rate after percutaneous treatment of early HCC was significantly better with RFA than with PEI but did not provide a clear survival advantage in cirrhotic patients.

[Hepatitis C, cirrhosis and hepatocellular carcinoma]

The screening for the detection of hepatocellular carcinoma is based on ultrasound sonography which should be realised in patients with post-hepatitis C cirrhosis with a delay between 3 and 6 months according to the most identified risk factors, in particular age and sex male. In the case of discovery of hypoechogen nodule < or = 1cm, a follow-up is mandatory because it is usually untypical by ultrasound sonography and to propose a liver biopsy in the case of an increasing in size is shown. The ultrasound guided cutting biopsy can precise the histological characteristics of the nodule, the grade, and indicate prognostic factors. The liver biopsy is also mandatory in the case of a nodule > 2 cm and when the ultrasound sonography is not contributive, especially when the nodule is between 1 and 2 cm in size.