Percutaneous radiofrequency thermal ablation for hepatocellular carcinoma

Progression of hepatocellular carcinoma after radiofrequency ablation: Current status of research

Hepatocellular carcinoma (HCC) remains an important disease for health care systems in view of its high morbidity, mortality, and increasing incidence worldwide. Radiofrequency ablation (RFA) is preferred to surgery as a local treatment for HCC because it is safer, less traumatic, less painful, better tolerated, causes fewer adverse reactions, and allows more rapid postoperative recovery. The biggest shortcoming of RFA when used to treat HCC is the high incidence of residual tumor, which is often attributed to the vascular thermal deposition effect, the wide infiltration zone of peripheral venules, and the distance between satellite foci and the main focus of the cancer. Recurrence and progression of the residual tumor is the most important determinant of the prognosis. Therefore, it is important to be aware of the risk of recurrence and to improve the efficacy of RFA. This review summarizes the relevant literature and the possible mechanisms involved in progression of HCC after RFA. Current studies have demonstrated that multimodal treatments which RFA combined with other anti-cancer approaches can prevent progression of HCC after RFA.

Hepatic abscess with hepatobronchial fistula following percutaneous radiofrequency ablation for hepatocellular carcinoma: A case report

Radiofrequency ablation (RFA) has a low rate of complication and is one of the most effective and minimally invasive techniques for the treatment of liver tumors. However, a number of complications may occur in rare cases, including bronchobiliary fistula, hollow viscera perforation, diaphragmatic perforation and hernia. The present study reports a case of hepatic abscess with hepatobronchial fistula following RFA of hepatocellular carcinoma; this led to severe lung infection, respiratory failure and mortality. The present case report aims to improve understanding of the cause and mechanism of the complications arising through RFA of the liver, and highlight important factors in the prevention and management process. This case indicates that the complications of RFA may be prevented or effectively managed through preoperative evaluation, intraoperative and postoperative monitoring.

Radiofrequency ablation versus laser ablation for the treatment of small hepatocellular carcinoma in cirrhosis: a randomized trial

BACKGROUND AND AIM

In patients with cirrhosis and small hepatocellular carcinoma (HCC), thermal ablation is currently recognized as an effective local treatment. Among thermal procedures, radiofrequency ablation (RFA) is the most diffusely used and is the standard against which any new treatment should be compared. In retrospective studies, laser ablation (LA) resulted as safe and effective as RFA. Therefore, we performed a non-inferiority randomized trial comparing RFA with LA in patients with cirrhosis and HCC within Milan criteria.

METHODS

Overall, 140 patients with 157 HCC nodules were randomly assigned to receive RFA or LA. The primary end-point was the proportion of complete tumor ablation (CTA). Secondary end-points were time to local progression (TTLP) and overall survival (OS).

RESULTS

Per patient CTA rates after RFA and LA were 97.4% (95% CI, 91.0-99.3) and 95.7% (88.1-98.5), respectively (difference = 1.4%, 95% CI from -6.0% to + 9.0%). Per nodule CTA rates for RFA and LA were 97.4% (91.0-99.3) and 96.3% (89.6-98.7), respectively (difference = 1.1%, from -5.7% to + 8.1%). The mean TTLP was comparable between RFA group (42.0 months; 95% CI, 36.83-47.3) and LA group (46.7 months; 95% CI, 41.5-51.9) (P = .591). The mean OS was 42 months in both groups and survival probability at 1 and 3 years was 94% and 89% in RFA group, and 94% and 80% in LA group.

CONCLUSION

LA resulted not inferior to RFA in inducing the CTA of HCC nodules and therefore it should be considered as an evaluable alternative for thermal ablation of small HCC in cirrhotic patients.

Frequency of and predictive factors for vascular invasion after radiofrequency ablation for hepatocellular carcinoma

BACKGROUND

Vascular invasion in patients with hepatocellular carcinoma (HCC) is representative of advanced disease with an extremely poor prognosis. The detailed course of its development has not been fully elucidated.

METHODS

We enrolled 1057 consecutive patients with HCC who had been treated with curative intent by radiofrequency ablation (RFA) as an initial therapy from 1999 to 2008 at our department. We analyzed the incidence rate of and predictive factors for vascular invasion. The survival rate after detection of vascular invasion was also analyzed.

RESULTS

During a mean follow-up period of 4.5 years, 6075 nodules including primary and recurrent lesions were treated by RFA. Vascular invasion was observed in 97 patients. The rate of vascular invasion associated with site of original RFA procedure was 0.66% on a nodule basis. The incidence rates of vascular invasion on a patient basis at 1, 3, and 5 years were 1.1%, 5.9%, and 10.4%, respectively. Univariate analysis revealed that tumor size, tumor number, alpha-fetoprotein (AFP), des-gamma-carboxy prothrombin (DCP), and Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein were significant risk predictors of vascular invasion. In multivariate analysis, DCP was the most significant predictor for vascular invasion (compared with a DCP of ≤100 mAu/mL, the hazard ratio was 1.95 when DCP was 101-200 mAu/mL and 3.22 when DCP was >200 mAu/mL). The median survival time after development of vascular invasion was only 6 months.

CONCLUSION

Vascular invasion occurs during the clinical course of patients initially treated with curative intent. High-risk patients may be identified using tumor markers.

Serum alpha-fetoprotein response can predict prognosis in hepatocellular carcinoma patients undergoing radiofrequency ablation therapy

AIMS

To evaluate the clinical inference of serum alpha-fetoprotein (AFP) response in hepatocellular carcinoma (HCC) patients undergoing percutaneous radiofrequency ablation (RFA).

MATERIALS AND METHODS

Three hundred and thirteen previously untreated HCC patients were enrolled in the study. The optimal AFP response was defined as >20% decrease from baseline after 1 month of RFA for those with a baseline AFP level of ≥100 ng/ml. The impact of AFP response on prognosis was analysed and prognostic factors were assessed.

RESULTS

After a median follow-up of 26.7 ± 19.1 months, 49 patients died and 264 patients were alive. The cumulative 5 year survival rates were 75.3 and 57.4% in patients with an initial AFP of <100 ng/ml and ≥100 ng/ml, respectively (p = 0.003). In the 58 patients with a baseline AFP of ≥100 ng/ml and initial completed tumour necrosis after RFA, the cumulative 5 year survival rates were 62.4 and 25.7% in optimal and non-optimal AFP responders, respectively (p = 0.001). By multivariate analysis, the prothrombin time international normalized ratio >1.1 (p = 0.009), non-optimal AFP response (p = 0.023), and creatinine >1.5 mg/dl (p = 0.021) were independent risk factors predictive of poor overall survival. Besides, the cumulative 5 year recurrence rates were 83.4 and 100% in optimal and non-optimal AFP responders, respectively (p < 0.001). Multivariate analysis demonstrated platelet count ≤10(5)/mm(3) (p = 0.048), tumour size >2 cm (p = 0.027), and non-optimal AFP response (p < 0.001) were independent risk factors associated with tumour recurrence after RFA.

CONCLUSIONS

Serum AFP response may be a useful marker for predicting prognosis in HCC patients undergoing RFA.

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.

Is percutaneous radiofrequency thermal ablation of hepatocellular carcinoma a safe procedure?

AIM

To assess the safety and efficacy of percutaneous radiofrequency thermal ablation (RFA) in the treatment of nonsurgical hepatocellular carcinoma (HCC) in daily practice.

METHODS

A total of 63 consecutive patients with HCC (solitary nodule <or=5 cm or 2 nodules <or=3 cm) and cirrhosis were treated with RFA. Majority of the patients had a compensated liver disease (73% Child A) and an early tumor stage (87% CLIP 0 or 1). Indications for treatment were primary HCC therapy (30 patients), adjuvant therapy before liver transplantation (15 patients) or palliation in the remaining 18 patients with progression of HCC despite previous antitumoral treatments. RFA was performed by a 100 kW electrical generator connected to an expandable 10-hook electrode.

RESULTS

Seventy-one lesions were treated in 80 sessions. Sixteen patients required adjuvant chemoembolization. Mean follow-up was 18+/-12 months. An objective response was achieved in 87% of patients who underwent primary/adjuvant treatment. Complete histological necrosis was found in 38% of patients who underwent liver transplantation. One, 2 and 3-year survival rates were 95, 76 and 72%, respectively in patients who underwent primary/adjuvant therapy and 82, 68 and 51%, respectively in patients who underwent palliative therapy. Major complications (hemoperitoneum, pleuritis, pneumothorax and sepsis) were observed in 6.3% of the patients. Notably, rapid neoplastic progression was observed in two patients within 2 months after a single RFA session (neoplastic portal thrombosis and plurifocal HCC in one patient and cutaneous seeding and lung metastases in another patient).

CONCLUSIONS

Majority of the HCC patients treated by percutaneous RFA can achieve local control of the tumor in HCCs less than or equal to 3 cm. As the procedure can be associated with major complications and cases of rapid neoplastic dissemination may occur, a more accurate selection of candidates to RFA treatment is advisable.

Radiofrequency ablation versus resection for resectable colorectal liver metastases: time for a randomized trial?

BACKGROUND

Surgical resection is the gold standard in the treatment of resectable colorectal liver metastases (CRLM). In several centers, resection is being replaced by radiofrequency ablation (RFA), even though there is no evidence yet from randomized trials to support this. The aim of this study was to critically review the oncological evidence for and against the use of RFA for resectable CRLM.

METHODS

An exhaustive review of RFA of colorectal metastases was carried out.

RESULTS

Five-year survival data after RFA for resectable CRLM are not available. Percutaneous RFA is associated with worse local control, worse staging, and a small risk of electrode track seeding when compared with resection (level V evidence). For tumors </=3 cm, local control after surgical RFA is equivalent to resection, especially if applied by experienced physicians to nonperivascular tumors (level V evidence). There is indirect evidence for profoundly different biological effects of RFA and resection.

CONCLUSIONS

A subgroup of patients has been identified for whom local control after RFA might be equivalent to resection. Whether this is true, and whether this translates into equivalent survival, remains to be proven. The time has come for a randomized trial.

Seeding following percutaneous diagnostic and therapeutic approaches for hepatocellular carcinoma. What is the risk and the outcome? Seeding risk for percutaneous approach of HCC

BACKGROUND

Tumour biopsy is usually considered mandatory for patient management by oncologists. Currently percutaneous ablation is used therapeutically for cirrhotic patients with small hepatocellular carcinoma (HCC), not suitable for resection or waiting for liver transplantation. However malignant seeding is a recognized complication of both diagnostic and therapeutic procedures in patients with HCC. Although percutaneous therapy whether with or without biopsy of a suspected HCC nodule may minimize the risk of seeding, this has not been confirmed.

AIM

To evaluate the risk of seeding, defined as new neoplastic disease occurring outside the liver capsule, either in the subcutaneous tissue or peritoneal cavity following needle biopsy and/or local ablation therapy (LAT).

METHODS

A literature search resulted in 179 events in 99 articles between January 1983 and February 2007: 66 seedings followed liver biopsy, 26 percutaneous ethanol injection (PEI), 1 microwave, 22 radiofrequency ablation (RFA), and 64 after combined biopsy and percutaneous treatment (5 microwave; 33 PEI; 26 RFA).

RESULTS

In 41 papers specifying the total number of patients biopsied and/or treated, the median risk of seeding was 2.29% (range 0-11%) for biopsy group; 1.4% (1.15-1.85%) for PEI when used with biopsy and 0.61% (0-5.56%) for RFA without biopsy, 0.95% (0-12.5%) for RFA with biopsy and 0.72% (0-10%) for liver nodules (including non-HCC nodules) biopsied and ablated.

CONCLUSION

Risk of seeding with HCC is substantial and appears greater with using diagnostic biopsy alone compared to therapeutic percutaneous procedures. This risk is particularly relevant for patients being considered for liver transplantation.