Significant long-term survival after radiofrequency ablation of unresectable hepatocellular carcinoma in patients with cirrhosis

Image-guided multipolar radiofrequency ablation of liver tumours: initial clinical results

The local effectiveness and clinical usefulness of multipolar radiofrequency (RF) ablation of liver tumours was evaluated. Sixty-eight image-guided RF sessions were performed using a multipolar device with bipolar electrodes in 53 patients. There were 45 hepatocellular carcinomas (HCC) and 42 metastases with a diameter < or =3 cm (n = 55), 3.1-5 cm (n = 29) and >5 cm (n = 3); 26 nodules were within 5 mm from large vessels. Local effectiveness and complications were evaluated after RF procedures. Mean follow-up was 17 +/- 10 months. Recurrence and survival rates were analysed by the Kaplan-Meier method. The primary and secondary technical effectiveness rate was 82% and 95%, respectively. The major and minor complication rate was 2.9%, respectively. The local tumour progression at 1- and 2-years was 5% and 9% for HCC nodules and 17% and 31% for metastases, respectively; four of 26 nodules (15%) close to vessels showed local progression. The survival at 1 year and 2 years was 97% and 90% for HCC and 84% and 68% for metastases, respectively. Multipolar RF technique creates ablation zones of adequate size and tailored shape and is effective to treat most liver tumours, including those close to major hepatic vessels.

Percutaneous Radiofrequency Ablation of Liver Tumors Using Multiple Saline-Perfused Electrodes

PURPOSE

Radiofrequency ablation (RFA) with multiple saline-perfused electrodes is a minimally invasive alternative to archive large coagulation zones. Few long-term results have been published so far. This is a report of our long-term experience using multiple saline-perfused electrodes for the treatment of malignant hepatic tumors.

MATERIALS AND METHODS

Thirty-eight patients with biopsy-proven hepatocellular carcinoma (HCC) or liver metastases of colorectal cancer (CRC) (17 CRC, 21 HCC) with a total of 56 tumors (26 CRC, 30 HCC) were treated with the Integra HiTT 106 RF generator using multiple saline-perfused electrodes. Mean size was 42 mm for HCC and 36 mm for CRC. Follow-up examinations took place after 2 days and 1, 3, 6, and 9 months after RFA and every 6 months thereafter.

RESULTS

We performed 2.6 (2.7 CRC, 2.4 HCC) sessions per patient. Major complications occurred in 2% of patients. Ninety-two percent (35/38) were treated technically successfully. Local tumor progression was found in 8 patients out of 35 (22% overall, 21% HCC, 25% CRC). For HCC, 43% of patients suffered distant intrahepatic recurrence. One- and two-year survival for HCC patients was 71% and 58%. (Child-Pugh status A, one- and two-year survival was 90% and 80%; Child status B, 35% and 18%). For CRC, 11 of 17 (65%) patients suffered distant intrahepatic recurrence. One- and two-year survival for CRC patients was 94% and 86%.

CONCLUSIONS

RFA using multiple saline-perfused electrodes shows results in the treatment of liver tumors comparable with other established ablation techniques.

Intrahepatic tumor recurrence after partial hepatectomy: value of percutaneous radiofrequency ablation

PURPOSE

To determine the risks and benefits of percutaneous radiofrequency (RF) ablation of recurrent hepatic tumors in patients who have undergone hepatic resection.

MATERIALS AND METHODS

Retrospective review of the institutional RF ablation database yielded 35 patients with recurrent hepatic tumor after hepatectomy. Sixty-one recurrent hepatic tumors (mean diameter +/- SD, 1.7 +/- 1.1 cm; range, 0.5-5.3 cm) were ablated percutaneously under sonographic guidance or combined guidance with sonographic and fluoroscopic computed tomography (CT). Follow-up CT, magnetic resonance imaging, or both were used for assessment of the primary and secondary therapeutic effectiveness rate and failure of RF ablation. Patients' survival status was determined by contacting the primary care physician or searching the Social Security Death Index.

RESULTS

Complete ablation was accomplished in 54 of 61 hepatic tumors (primary therapeutic effectiveness rate, 88.5%). During a mean follow-up time of 18 months (range, 1-65 months), 14.8% of the tumors (n = 9) were incompletely ablated. Three of the nine incompletely ablated tumors were treated with a second RF ablation, all three of which failed (secondary therapeutic effectiveness rate, 0%). Distant intrahepatic tumor progression appeared in 23 of 35 patients (65.7%). One major complication (2.1%, one of 48 sessions) and eight minor complications (16.7%, eight of 48 sessions) were reported. The major complication was hepatic abscess formation. The overall survival rates for all patients at 1, 2, and 3 years were 76%, 68%, and 45%, respectively. For patients with metastases from colorectal cancer (n = 14), the overall survival rates were 72%, 60%, and 60% at 1, 2, and 3 years, respectively; and for patients with hepatocellular carcinoma (n = 8), the overall survival rates were 72%, 58%, and 44% at 1, 2, and 3 years, respectively.

CONCLUSION

Percutaneous RF ablation offers a safe and effective treatment option for recurrent hepatic tumors after previous partial hepatectomy.

Experimental and Clinical Radiofrequency Ablation: Proposal for Standardized Description of Coagulation Size and Geometry

BACKGROUND

Radiofrequency (RF) ablation is used to obtain local control of unresectable tumors in liver, kidney, prostate, and other organs. Accurate data on expected size and geometry of coagulation zones are essential for physicians to prevent collateral damage and local tumor recurrence. The aim of this study was to develop a standardized terminology to describe the size and geometry of these zones for experimental and clinical RF.

METHODS

In a first step, the essential geometric parameters to accurately describe the coagulation zones and the spatial relationship between the coagulation zones and the electrodes were defined. In a second step, standard terms were assigned to each parameter.

RESULTS

The proposed terms for single-electrode RF ablation include axial diameter, front margin, coagulation center, maximal and minimal radius, maximal and minimal transverse diameter, ellipticity index, and regularity index. In addition a subjective description of the general shape and regularity is recommended.

CONCLUSIONS

Adoption of the proposed standardized description method may help to fill in the many gaps in our current knowledge of the size and geometry of RF coagulation zones.

Technology insight: Image-guided therapies for hepatocellular carcinoma--intra-arterial and ablative techniques

Locoregional techniques have become the mainstay of therapy for patients with unresectable hepatocellular carcinoma (HCC). Such image-guided interventions include catheter-based approaches (transarterial chemoembolization and yttrium-90 radiotherapy) and locoregional ablative techniques, either chemical (percutaneous ethanol injection), or thermal (radiofrequency ablation, laser ablation, microwave ablation and cryoablation). These therapies are mainly utilized for palliation, but have also been used with curative intent. In selected cases, percutaneous interventional treatments have shown good results (5-year survival 40-50%), but, even when chosen as first-line treatment, have not been able to achieve the response rates and outcomes achieved by surgical options (resection or transplantation). New promising image-guided therapies are continuously emerging, as we attempt to improve tumor targeting, minimize hepatic toxicity and ultimately improve quality of life and survival of patients with HCC. With new technologies in imaging and drug delivery becoming available, it is likely that, in the future, patients with HCC will be best treated by a multidisciplinary team approach, utilizing a combination of techniques to improve patient survival. This review outlines the current status of the most commonly used image-guided locoregional interventions in the treatment of patients with HCC, and describes recent research and advances related to image-guided interventions for liver cancer.

Radio-frequency ablation of hepatocellular carcinoma before liver transplantation: a histologic and 'TUNEL' study

BACKGROUND

Radio-frequency ablation (RFA) is an increasingly used treatment modality for hepatocellular carcinoma (HCC) in patients awaiting liver transplantation (OLTX). The current study evaluates the effectiveness of RFA in this setting based on evaluation of total cell death in explanted native livers.

DESIGN

We evaluated 36 tumors from 35 patients with RFA-treated HCC who underwent OLTX at our center between 1998 and 2002. Native livers from OLTX were extensively sampled for histologic evaluation. For each HCC, an estimate ratio of necrotic tumor areas was calculated based on hematoxylin and eosin (H&E) sections. In tumors with 10% or more residual viable areas, Tdt-mediated UTP nick-end labeling (TUNEL) was further performed to assess apoptosis in the morphologically 'viable' areas. A final 'tumor cell death' (TCD) ratio was recalculated for each HCC to include areas of apoptosis identified by TUNEL.

RESULTS

Based on H&E evaluation, 22/36 (61.1%) HCC revealed > or = 90% necrosis including 12/36 HCC (33.3%) showing no evidence of residual viable tumor. The overall median tumor necrosis was 79%. When TUNEL findings were added, 26/36 (72.2%) HCC revealed > or = 90% TCD including 14/36 HCC (38.8%) showing complete TCD (median TCD of 88.4%). None of our patients died of HCC while awaiting OLTX. Longer RFA-to-transplant time appears to be associated with a higher TCD rate (median of 154.5 days in patients with less than 90% TCD vs 326 days for patients with > or = 90% TCD; P = 0.019). There was no significant correlation between tumor grade or pre-RFA size of the tumors and TCD rate in RFA-treated HCC (P = 0.11).

CONCLUSION

Extensive TCD (88.4% median) can be obtained using RFA for HCC in patients awaiting OLTX. Our TUNEL findings suggest that RFA-induced cell injury could be associated with apoptosis.

Radiofrequency ablation of lung tumours

Radiofrequency ablation (RFA) is a well-established local therapy for hepatic malignancies. It is rapidly emerging as an effective treatment modality for small lesions elsewhere in the body, in particular, the kidney and the lung. It is a relatively safe and minimally invasive treatment for small lung malignancies, both primary and secondary. In particular, it is the preferred form of treatment for non-surgical candidates.

This paper describes the technique employed for radiofrequency ablation of lung tumours, as well as the protocol established, at the Mount Elizabeth Hospital, Singapore.

Is there a role for immunotherapy in hepatocellular carcinoma?

Incidence of hepatocellular carcinoma has been rising in the last two decades because of the wide exposure to hepatitis C virus during 1960s and 1970s. Improvement in treatment has been achieved by local ablative therapies, however because of early recurrence and lack of effective chemotherapies, alternative treatments based on stimulation of the anti-tumour immune response could represent new strategies to control hepatocellular carcinoma spread and recurrence. Proof of principle of an effective immunotherapy has been achieved for other solid tumours such as melanoma and several results could be transferred to the immunotherapy of hepatocellular carcinoma. Specific tumour antigens have been identified in hepatocellular carcinoma, such as cancer testis antigens expressed in a large part of hepatocellular carcinomas and alpha-fetoprotein that has been already employed in clinical trials demonstrating immunogenicity without however significant clinical efficacy. Better results have been achieved by non-antigen-specific immunotherapies that demonstrated improvement in recurrence and recurrence-free survival in patients undergoing surgical resection for hepatocellular carcinoma. Passive immunotherapy and targeted therapies blocking tumour cell receptors or enzymatic pathways are already in the clinic for other malignancies and the near future will see these new treatments applied to hepatocellular carcinoma patients along with the development of efficacious active immunotherapies aimed at reducing disease recurrence and improving survival.

Laparoscopic radiofrequency ablation of hepatic cavernous hemangioma. A preliminary experience with 27 patients

BACKGROUND

Radiofrequency ablation (RFA), currently used extensively for liver tumors, also has been applied successfully to hepatic cavernous hemangioma (HCH) percutaneously. The aim of this study was to assess the feasibility, safety, and efficacy of laparoscopic RFA for patients with HCHs.

METHODS

Between March 2001 and March 2004, 27 patients with symptomatic and rapid-growth lesions were treated by laparoscopic RFA using the RF-2000 generator system. The treatment-related complications were observed. All the patients were followed up with helical computed tomography scans and ultrasonography at regular intervals to assess the therapeutic efficacy of laparoscopic RFA.

RESULTS

This study assessed 9 men and 18 women with a mean age of 41.6 +/- 8.3 years. Three additional intrahepatic lesions missed preoperatively were found in three patients on intraoperative ultrasound. A total of 27 patients with 50 liver lesions were treated successfully with laparoscopic RFA. The mean maximum tumor diameter was 5.5 +/- 2.0 cm. The mean length of time for RFA per lesion was 20.7 +/- 11.9 min, and the mean blood loss was 134.4 +/- 88.9 ml. Laparoscopic cholecystectomy was performed simultaneously for gallstones in 13 patients and for abutting of gallbladder from hemangioma in 2 patients. In addition, 3 patients also had a laparoscopic deroofing of simple hepatic cysts. Although postoperative low-grade fever and transient elevation of serum transaminase levels were observed in 13 patients, there were no complications related to laparoscopic RFA. During a median follow-up period of 21 months (range, 12-42 months), complete lesion necrosis was achieved for all the patients.

CONCLUSIONS

Laparoscopic RFA therapy is a safe, feasible, and effective treatment option for patients with symptomatic and rapid-growth HCHs located on the surface of the liver or adjacent to the gallbladder. Intraoperative ultrasonography is a useful adjunct for detecting additional liver lesions and offering more accurate targeting for RFA.