Ultrasound-guided percutaneous ethanol injection under general anesthesia for the treatment of hepatocellular carcinoma on cirrhosis: long-term results in 268 patients

A new sonoablation using acoustic droplet vaporization and focused ultrasound: A feasibility study

BACKGROUND

Histotripsy and boiling histotripsy are two methods of mechanical ablation that use high-pressure focused ultrasound (FUS).

PURPOSE

Here, a new bubble sonoablation technique was investigated using low-pressure FUS in combination with local injection of perfluoropentane (PFP) in rabbit liver.

METHODS

Fifteen healthy New Zealand white rabbits were treated with FUS alone, FUS + PFP or PFP alone. FUS was performed using a single-element focused transducer (frequency 596 kHz, 0.27 ms pulses, 0.54% duty cycle, and peak negative pressure 2.0 MPa). Ten minutes before FUS treatment, the PFP droplet was locally injected into the rabbit liver, where the ultrasound was focused. Contrast-enhanced ultrasound (CEUS) of the liver was performed, and the temperature at the liver surface in the targeted liver region was recorded during treatment. The livers were collected for pathological examination. Statistical significance was set at p < 0.05. Paired t-tests were used to compare the pre- and post-treatment values. One-way analysis of variance was performed to compare multiple groups, and the least significant difference method was used for further comparisons between the two groups.

RESULTS

Analysis of CEUS data showed that the values of area under the curve (AUC) were significantly different in the PFP + FUS group pre- (10453.644 ± 1182.93) and post-treatment (4058.098 ± 2720.41), and the AUC values of PFP + FUS post-treatment (4058.098 ± 2720.41) were also significantly lower than those of the FUS (9946.694 ± 1071.54) and the PFP (10364.794 ± 2181.53) groups. The peak intensity values also showed the same results, the value of peak intensity of PFP+FUS post-treatment was 82.958 ± 13.99, whereas there was no difference between FUS (106.61 ± 7.61) and PFP (104.136 ± 10.55). Hematoxylin and eosin (H&E) staining revealed that the pathological damage ratings of the PFP + FUS, PFP, and FUS groups were grade 3, grade 1, and grade 0, respectively. Specifically, the area of liver necrosis in the PFP + FUS group (0.99 ± 0.29 cm2 ) was 198 times higher than that in the PFP group (0.005 ± 0.008 cm2 ), whereas no necrosis was observed in the livers treated with FUS alone. Simultaneously, the number of vacuoles in the liver of the PFP + FUS group (35.50 ± 23.31) was approximately five times that of the PFP group (7.00 ± 12.88), whereas no vacuoles were found in the liver treated with FUS alone.

CONCLUSION

PFP droplets combined with FUS can destroy liver tissue and cause tissue necrosis in the droplet injection area, without affecting the structure of surrounding tissue.

Quantitative Dual-Energy CT Image Guidance for Thermochemical Ablation: In Vivo Results in the Rabbit VX2 Model

PURPOSE

To evaluate the feasibility of using dual-energy computed tomography (CT) and theranostic cesium hydroxide (CsOH) for image guidance of thermochemical ablation (TCA) in a rabbit VX2 tumor model.

MATERIALS AND METHODS

In vivo experiments were performed on New Zealand white rabbits, where VX2 tumor fragments (0.3 mL) were inoculated into the right and left flanks (n = 16 rabbits, 32 tumors). Catheters were placed in the approximate center of 1- to 2-cm diameter tumors under ultrasound guidance. TCA was delivered in 1 of 3 treatment groups: untreated control, 5-M TCA, or 10-M TCA. The TCA base reagent was doped with 250-mM CsOH. Dual-energy CT was performed before and after TCA. Cesium (CS)-specific images were postprocessed on the basis of previous phantom calibrations to determine Cs concentration. Line profiles were drawn through the ablation center. Twenty-four hours after TCA, subjects were euthanized, and the resulting damage was evaluated with histopathology.

RESULTS

Cs was detected in 100% of treated tumors (n = 21). Line profiles indicated highest concentrations at the injection site and decreased concentrations at the tumor margins, with no Cs detected beyond the ablation zone. The maximum detected Cs concentration ranged from 14.39 to 137.33 mM. A dose-dependent trend in tissue necrosis was demonstrated between the 10-M TCA and 5-M TCA treatment groups (P = .0005) and untreated controls (P = .0089).

CONCLUSIONS

Dual-energy CT provided image guidance for delivery, localization, and quantification of TCA in the rabbit VX2 model.

Ultrasound-guided percutaneous irreversible electroporation of hepatic and abdominal tumors not eligible for surgery or thermal ablation: a western report on safety and efficacy

PURPOSE

To report our first results on sixteen patients affected by liver and abdominal malignant tumors, unfit for surgery or thermal ablation, treated with US-guided percutaneous irreversible electroporation (IRE).

METHODS

From June 2014 to December 2016, all patients meeting the inclusion criteria (malignant hepatic or abdominal tumors not eligible for resection or thermal ablation) and not meeting the exclusion criteria (heart arrhythmia, pro-hemorrhagic hematological alterations, tumor size > 8 cm, presence of a biliary metallic stent) referred to our institutions were prospectively enrolled to undergo percutaneous US-guided irreversible electroporation (IRE). Sixteen patients (age range 59-68 years, mean 63; 7 females) with 18 tumors (diameter range 1.3-7.5 cm) fulfilled the inclusion criteria and were included in the study. Data concerning efficacy (tested by a 1-week CEUS and a 4-week enhanced CT and/or enhanced MRI) and safety were recorded during a 18-month follow up.

RESULTS

All patients completed a 35-50-min procedure without complications. One patient with 6 cm Klatskin tumor also underwent a second session for 1 month. A 1-week CEUS and a 4-week e-CT and/or e-MRI arterial phase contrast enhancement analysis showed an overall reduction of arterial flow with confirmation of unenhanced lesions for seven nodules. After 1-18 months of follow up, no major complications were recorded and no tumor-related death occurred. The lesions of two patients disappeared 3 and 6 months after their treatment, respectively.

CONCLUSIONS

IRE is a promising ablation modality in the treatment of malignant hepatic and abdominal tumors unsuitable for resection or thermal ablation.

Microwave Ablation in Intermediate Hepatocellular Carcinoma in Cirrhosis: An Italian Multicenter Prospective Study

Background and Aims: To report long-term results in treatment of intermediate hepatocellular carcinoma (HCC) in cirrhotics using new high-powered microwaves (MWS) ablation alone. Methods: This multicenter study included 215 cirrhotics (age range: 67-84 years; 137 males; 149 Child A, 66 Child B) who underwent percutaneous ultrasound-guided high-powered MWS ablation instead of transarterial chemoembolization. Among the patient population, 109 had a single nodule (Ø 5.3-8 cm) [group A], 70 had 2 nodules (Ø 3-6 cm) [group B] and 36 had 3-5 nodules (Ø 1.5-6.8 cm) [group C]. MWS ablation efficacy was evaluated using enhanced-computed tomography and/or magnetic resonance imaging. Primary end-point was 5-year cumulative overall survival (OS). Results: On enhanced-computed tomography and/or magnetic resonance imaging, complete ablation rates were 100% for 1.5-3.5 cm nodules. In nodules >3.5-5 cm, it was 89% for the first ablation and 100% for the second. For lesions >5-8 cm, ablation was up to 92%. Overall, 1-, 3- and 5-year survival rates were 89, 60, and 21%, respectively. The cumulative OS rate of group A was 89%, 66% and 34% at 1, 3 and 5 years. The cumulative OS rate of group B was 88%, 60% and 11% at 1, 3 and 5 years. The cumulative OS rate of group C was 86%, 55% and 0%. The 5-year survival rate was significantly different among the groups (p <0.001). One patient died from rupture of HCC. Upon multivariate analysis, preablation total bilirubin >1.5 mg/dL was an independent factor for predicting lower survival. Conclusions: Percutaneous MWS ablation of intermediate HCC is safe and effective in inducing large volume of necrosis in intermediate HCC nodules, providing long-term survival rates similar to transarterial chemoembolization. Preablation total bilirubin >1.5 mg/dL as expression of liver function reserve is the main factor predicting a worse outcome.

The effects of percutaneous ethanol injection followed by 20-kHz ultrasound and microbubbles on rabbit hepatic tumors

OBJECTIVE

Low-frequency ultrasound (US) in combination with microbubbles (MBs) is able to inhibit the growth of VX2 rabbit liver tumors. In this study, we investigated the feasibility of using percutaneous ethanol injection (PEI) followed by low-frequency ultrasound and microbubbles (USMB) to inhibit VX2 tumor growth.

METHODS

Eighteen New Zealand rabbits with hepatic VX2 tumors were divided into three groups: PEI, low-frequency ultrasound and MBs followed by PEI (USMB + PEI), and PEI followed by USMB (PEI + USMB). PEI was performed by ultrasound-guided injection of 95% anhydrous alcohol into internal liver tumors in rabbits twice a week for 2 weeks. The US parameters were 20 kHz, 2 W/cm(2), 40% duty cycle, 5 min, and once every other day for 2 weeks. Magnetic resonance imaging (MRI) was used to observe tumors before and after treatment, to examine changes in the tumors, and to measure the diameters of the tumors. All animals were followed up for 180 days after tumor implantation. Autopsy was performed at the end of the scheduled follow-up or immediately after death. Anatomically observed metastatic sites included the liver, lung, abdomen, and pelvic cavity. The survival time of all rabbits was recorded.

RESULTS

After 4 weeks of treatment, on MRI, the tumor diameters in the PEI, USMB + PEI, and PEI + USMB groups were 8.33 ± 1.83, 19 ± 2.61, and 4.5 ± 1.22 mm, respectively. There was a significant difference in tumor size indicated by MRI in the three groups. Tumor size was smaller in the PEI + USMB group than in the PEI and USMB + PEI groups, with t = 4.54, p = 0.0062, and t = 16.38, p < .0001, respectively. The PEI + USMB group showed the fewest metastasis sites (χ(2) = 11.7333, p = 0.0194) and the longest survival period (χ(2) = 7.448, p = 0.0241).

CONCLUSION

Percutaneous ethanol injection followed by low-frequency ultrasound and microbubbles can be effective in inhibiting rabbit liver tumors and prolonging survival time.

Hepatocellular carcinoma invading portal venous system in cirrhosis: long-term results of percutaneous radiofrequency ablation of both the nodule and portal vein tumor thrombus. A case control study

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death. Portal vein tumor thrombus (PVTT) is one of the most dreadful complications of HCC and is associated with a median survival time of 2.7-4.0 months. The optimal treatment for HCC with PVTT has not yet been established. The aim of the present study was to report long-term results of percutaneous radiofrequency (RF) ablation of both HCC single nodule (up to 5 cm in diameter) and neoplastic main portal vein thrombus, compared to no-treatment.

PATIENTS AND METHODS

From January 2005 to January 2010, out of 2,847 consecutive cirrhosis patients, 672 had HCC and main portal vein tumor thrombus (MPVTT); among these, 57 had a single HCC with MPVTT. Thirty-five patients with 35 single HCC nodules (ranging from 3.7 to 5 cm in diameter) underwent percutaneous RF ablation of both the nodule and the thrombus (cases); 22 patients refused RF ablation or any other treatment (controls).

RESULTS

A complete necrosis of HCC nodules associated with re-canalization of main portal trunk (MPT) and its branches were observed in 26 patients (success rate=74%). The 1-, 3- and 5-year cumulative survival rates of patients were 63%, 30% and 20%, respectively. The 12-month cumulative survival rate of controls was 0% (p<0.0001). The difference was statistically significant (p<0.001; harzard ratio (HR)=2.88; 95% confidence interval (CI)=1.57-5.39). The 3- and 5-year cumulative disease-free survival rates of the patients were 35% and 22%, respectively. No deaths occurred.

CONCLUSION

RF ablation of HCC and the accompanying MPVTT significantly prolongs long-term survival compared to no-treatment. The procedure is safe and should be considered as a new and effective tool in the treatment of advanced HCC.

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.

Percutaneous ethanol ablation of hepatocellular carcinoma: periprocedural onset alcohol toxicity and pancreatitis following conventional percutaneous ethanol ablation treatment

A novel case of acute pancreatitis in a patient treated with percutaneous ethanol injection (PEI) ablation for hepatocellular carcinoma is described. The most commonly reported adverse effects of PEI are hepatic or peritoneal hemorrhage, hepatic insufficiency or infarction. There are no previous reports of fatal acute pancreatitis as a result of conventional PEI.

Radiofrequency ablation of hepatocellular carcinoma extended into the portal vein: Preliminary results

INTRODUCTION

We report our preliminary results of radiofrequency (RF) ablation of hepatocellular carcinoma (HCC) and neoplastic portal thrombus (NPT) in cirrhotic patients.

METHODS

Ten patients (7 males and 3 females; mean age 68 yrs) with 10 HCC nodules (37-49 mm) extended into the main portal vein (MPV) underwent RF ablation. Diagnosis of NPT was achieved by fine-needle biopsy. RF ablation was performed firstly on the NPT and then on the HCC. RF ablation was considered successful when complete necrosis of the HCC and complete recanalization of the MPV were achieved. HCC necrosis was evaluated using contrast-enhanced CT. Recanalization of the portal vessels (PV) was analyzed using Color Doppler (CD). RF ablation was performed under ultrasonographic (US) guidance using a perfused electrode needle.

RESULTS

Complete necrosis of the HCC with complete recanalization of the PV was observed in 7 patients (success rate: 70%). In the remaining 3, necrosis of the HCC ranged from 70% to 95%, and recanalization of the PV was not complete. No major complications occurred. In 2 cases, mild ascites and increased aspartate aminotransferase/alanine aminotransferase (AST/ALT) values were observed. The follow-up ranged from 4 to 24 months; 1 and 2-year survival rates were 77% and 77%, respectively. At the last follow-up, the 7 successful patients were alive and the portal system was still patent. The 3 unsuccessful patients died within 5 months due to progressive disease.

CONCLUSION

RF ablation can destroy HCC and NPT achieving a high rate of efficacy and low rate of complications. However, to confirm these results a control group and a longer follow-up are required.

Chemical ablation of liver cancer

Percutaneous chemical ablation is an established image-guided therapy for liver cancer that is relatively simple to perform and requires no specialized equipment. Chemical ablation has been used extensively for hepatocellular carcinoma (HCC), and has achieved outcomes comparable to surgical resection for small, solitary HCC. More recent experience with chemical ablation has combined it with TACE or thermal ablation as part of a multimodality approach to liver cancer.

Ethanol versus radiofrequency ablation for the treatment of small hepatocellular carcinoma in patients with cirrhosis: a retrospective study of efficacy and cost

OBJECTIVE

To compare cost effectiveness of radio-frequency (RF) ablation versus percutaneous ethanol (Pe) ablation for treatment of small hepatocellular carcinoma.

METHODS

57 patients with 72 hepatocellular carcinomas (HCC) treated with ethanol ablation were retrospectively compared with 60 new patients who had 72 HCC treated with RF ablation. All patients had Child-Pugh A cirrhosis and HCC less than 3.5 cm in diameter. Therapeutic efficacy was evaluated with tri-phase spiral computed tomography. Cost of hospital stay, supplies and follow-up including complications were calculated. Survival was estimated by Kaplan-Meier method and prognostic value of treatment methods by Log Rank test and multivariate Cox proportional hazard model.

RESULTS

The two groups had similar baseline characteristics. The rate of severe complications associated with RF was 15% (9/60) vs 6,9% (9/60) with Pe (P=0,11) The two-year overall survival, disease free survival and local tumor free survival in the ethanol and radiofrequency groups were 70.8% vs. 91.2% (Odd Ratio=3.7, P=0.006), 48.6% vs. 71.1% (Odd Ratio=2.2, P=0.01), and 68.5% vs. 80.7%, (Odd Ratio=1.9; P=0.09), respectively. The treatment method was the sole significant factor related to overall and tumor free survival. Costs per patient of ethanol and radiofrequency treatments were 1534 euro and 1196 euro, respectively.

CONCLUSION

This retrospective study suggests that RF is the most cost effective strategy, with higher 2-year disease free survival rate.

Percutaneous Ethanol Injection of Unresectable Medium-to-Large-Sized Hepatomas Using a Multipronged Needle: Efficacy and Safety

Fine needles with an end hole or multiple side holes have traditionally been used for percutaneous ethanol injection (PEI) of hepatomas. This study retrospectively evaluates the safety and efficacy of PEI of unresectable medium-to-large (3.5-9 cm) hepatomas using a multipronged needle and with conscious sedation. Twelve patients, eight men and four women (age 51-77 years; mean: 69) received PEI for hepatomas, mostly subcapsular or exophytic in location with average tumor size of 5.6 cm (range: 3.5-9.0 cm). Patients were consciously sedated and an 18G retractable multipronged needle (Quadrafuse needle; Rex Medical, Philadelphia, PA) was used for injection under real-time ultrasound guidance. By varying the length of the prongs and rotating the needle, the alcohol was widely distributed within the tumor. The progress of ablation was monitored by contrast-enhanced ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI) after each weekly injection and within a month after the final (third) injection and 3 months thereafter. An average total of 63 mL (range: 20-154 ml) of alcohol was injected per patient in an average of 2.3 sessions. Contrast-enhanced CT, ultrasound, or MRI was used to determine the degree of necrosis. Complete necrosis was noted in eight patients (67%), near-complete necrosis (90-99%) in two (16.7%), and partial success (50-89%) in two (16.7%). Follow-up in the first 9 months showed local recurrence in two patients and new lesions in another. There was no mortality. One patient developed renal failure, liver failure, and localized perforation of the stomach. He responded to medical treatment and surgery was not required for the perforation. One patient had severe postprocedural abdominal pain and fever, and another had transient hyperbilirubinemia; both recovered with conservative treatment. PEI with a multipronged needle is a new, safe, and efficacious method in treating medium-to-large-sized hepatocellular carcinoma under conscious sedation. Its survival benefits require further investigations.

Combination of repeated single-session percutaneous ethanol injection and transarterial chemoembolisation compared to repeated single-session percutaneous ethanol injection in patients with non-resectable hepatocellular carcinoma

AIM: To evaluate the treatment effect of percutaneous ethanol injection (PEI) for patients with advanced, non-resectable HCC compared with combination of transarterial chemoembolisation (TACE) and repeated single-session PEI, repeated single-session PEI alone, repeated TACE alone, or best supportive care.

METHODS: All patients who received PEI treatment during the study period were included and stratified to one of the following treatment modalities according to physical status and tumor extent: combination of TACE and repeated single-session PEI, repeated single-session PEI alone, repeated TACE alone, or best supportive care. Prognostic value of clinical parameters including Okuda-classification, presence of portal vein thrombosis, presence of ascites, number of tumors, maximum tumor diameter, and serum cholinesterase (CHE), as well as Child-Pugh stage, α-fetoprotein (AFP), fever, incidence of complications were assessed and compared between the groups. Survival was determined using Kaplan-Meier and multivariate regression analyses.

RESULTS: The 1- and 3-year survival of all patients was 73% and 47%. In the subgroup analyses, the combination of TACE and PEI (1) was associated with a longer survival (1-, 3-, 5-year survival: 90%, 52%, and 43%) compared to PEI treatment alone (2) (1-, 3-, 5-year survival: 65%, 50%, and 37%). Secondary PEI after initial stratification to TACE (3) yielded comparable results (1-, 3-, 5-year survival: 91%, 40%, and 30%) while PEI after stratification to best supportive care (4) was associated with decreased survival (1-, 3-, 5-year survival: 50%, 23%, 12%). Apart from the chosen treatment modalities, predictors for better survival were tumor number (n < 5), tumor size (< 5 cm), no ascites before PEI, and stable serum cholinesterase after PEI (P < 0.05). The mortality within 2 wk after PEI was 2.8% (n = 3). There were 24 (8.9%) major complications after PEI including segmental liver infarction, focal liver necrosis, and liver abscess. All complications could be managed non-surgically.

CONCLUSION: Repeated single-session PEI is effective in patients with advanced HCC at an acceptable and manageable complication rate. Patients stratified to a combination of TACE and PEI can expect longer survival than those stratified to repeated PEI alone. Furthermore, patients with large or multiple tumors in good clinical status may also profit from a combination of TACE and reconsideration for secondary PEI.

Hepatocellular carcinoma: current treatment strategies

Hepatocellular carcinoma (HCC) is an increasingly prevalent clinical problem. The presence of cirrhosis in the majority of patients makes treatment difficult because both the stage of the tumor and the stage of cirrhosis must be taken into account. This is compounded by the difficulty in diagnosing HCC in the early stages, where treatment is most effective, and the lack of a globally accepted treatment policy. Liver transplantation and liver resection are the optimal treatments, with resection being preferred in patients with small lesions, clinically well-preserved liver function, and absence of portal hypertension. Patients unsuitable for these procedures, due to localized but large tumor bulk, are only treatable by ablative and palliative therapies. Ablation involves either thermal (preferably radiofrequency ablation) or chemical methods, with the choice of method being dependent on both the size and placement of the tumor and the operator. Ablation may also be used as a bridge to transplantation in centers where significant waiting times are anticipated. Tumors that are too large in size or number to ablate are treated with transarterial chemoembolization, involving the distribution of chemotherapeutic agents and the blocking of the blood supply to the tumor; this is not considered a curative therapy. Combination therapies may also be used. These treatment options need further evaluation for determination of the optimal course of therapy for individual patients.

Outcome of regional and local ablative therapies for hepatocellular carcinoma: a collective review

BACKGROUND

Transcatheter arterial (chemo) embolization (TACE), cryoablation (CA) and percutaneous ethanol injection (PEI) were the first regional and local ablative techniques that came into use for irresectable HCC. Radiofrequency ablation (RFA) and interstitial laser coagulation (ILC) followed and have now evolved rapidly. It would not be ethical to compare resection with ablation in patients well enough to undergo major surgery. Therefore, hepatic resection and hepatic transplantation remain the only curative treatment options for HCC.

METHODS

On the basis of a Medline literature search and the authors' experiences, the principles, current status and prospects of TACE and local ablative techniques in HCC are reviewed.

RESULTS

Complete tumour necrosis can be achieved in 60-100% of patients treated with PEI (70-100%), cryoablation (60-85%), RFA (80-90%) or ILC (70-97%). After TACE significant tumour response is achieved in 17-61.9% but complete tumour response is rare (0-4.8%) as viable tumour cells remain after TACE. Five-year survival rates are available for TACE (1-8%), PEI (0-70%) and cryoablation (40%). Only PEI and RFA were compared in one RCT. RFA was associated with fewer treatment sessions and a higher complete necrosis rate. Furthermore, all techniques are associated with low morbidity and mortality, but cryoablation seems to be associated with a higher morbidity rate.

CONCLUSION

TACE has shown to be a valuable therapy with survival benefits in strictly selected patients with unresectable HCC. RFA and PEI are now considered as the local ablative techniques of choice for the treatment of, preferably small, HCC. When tumours are located close to bile ducts or large vessels, PEI remains a valuable therapy. Completeness of ablation can be more easily monitored during cryoablation and another advantage of cryoablation is the possibility of edge freezing. The results of ILC are comparable to RFA with only few side effects and high tumour response rates.

Pharmacotherapy of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the more common causes of cancer death worldwide. It occurs on a background of chronic liver disease or viral hepatitis in the vast majority of cases, with hepatitis C being mostly responsible for its continuing rise in western countries. With the screening of at-risk groups, up to 70% of HCC lesions will be detected at a treatable stage but at best, only 20-30% will benefit from potentially curative hepatic resection or transplantation. How best to treat the remaining nonsurgical patients is an area of much debate and no ideal treatment is yet available. This review summarises some of the therapeutic modalities used for HCC, with an emphasis on pharmacological therapies.

Experimental and clinical assessment of percutaneous hepatic quantified ethanol injection in treatment of hepatic carcinoma

AIM: To detect the relationship between absolute ethanol injection quantity, the interval and formation of fibreboard, the curative effect in treatment of hepatocarcinoma and to evaluate the clinical application of percutaneous hepatic quantified ethanol injection (PHQEI) in treatment of hepatic carcinoma (HCC).

METHODS: (1) Experimental study: Twenty-four human hepatic carcinoma SMMC-7721 xenografted nude mice were randomly divided into three groups: Group A injected with quantified ethanol at short intervals (QESI), group B with quantified ethanol at long intervals (QELI) and group C with a small quantity of ethanol at long intervals (SQLI). The tumor tissues were sent for patho-histology and electron microscopic examinations. The diameters of tumors were measured with high frequency ultrasound before and after therapies and tumor growth index (TGI) was calculated. (2) Clinical study: Tumors of 122 cases of pathologically proved HCC were injected with quantified ethanol guided by ultrasound every 3-5 d 4-10 times per period of treatment. The quantity of ethanol was calculated according to the regressive equations where Y = 2.885X when the mass was ≤ 5 cm in diameter and Y = 1.805X when the mass was > 5 cm in diameter (X is the maximal diameter of the mass with the unit cm, Y is the ethanol quantity with the unit mL). The survival rates of 1, 2, 3 and 4 years and recurrent rates in situ as well as dystopia in the liver were calculated.

RESULTS: (1) Experimental study: TGI of QESI group (0.072 ± 0.018) and QELI group (0.094 ± 0.028) was apparently lower than that of SQLI group (1.982 ± 0.482) (P < 0.01). TGI of QESI group seemed to be lower than that of QELI group, but it was not markedly different (P > 0.05) between two groups. Severe degeneration and necrosis could be seen in QESI group by patho-histology examination. Coagulative necrosis could be seen in most tumors of QESI group and there were no residual cancer cells under electronic microscope, while the residual cancer and inflammatory cells and fibre tissues could be seen around the tumors of QELI group. Infiltration of inflammatory cells could be seen and fibre tissues were formed. (2) Clinical study: B mode ultrasound showed that 62.5% of tumors shrank after PHQEI. The survival rates of 1, 2, 3 and 4 years of the group with tumors ≤ 3 cm in diameter were higher than those of the group with tumors > 3 cm in diameter. The recurrent rates of tumors in situ of the former group were apparently lower than those of the latter group. The recurrent rates of tumors in dystopia in the liver of the former group were markedly lower than those of the latter group. The 122 cases underwent a total of 1221 PEI. There were no complications such as hemorrhage and severe heart, liver and kidney functional injuries except for 1 case of melena and 4 cases of jaundice who recovered after 1-2 wk under common therapies.

CONCLUSION: The experimental study shows quantified ethanol at intervals of 3-5 d could improve the curative effect of hepatocarcinoma. The clinical study shows PHQEI is an effective therapeutic method for HCC with few side-effects, and a low-cost. The treatment efficacy is more remarkable for tumors ≤ 3 cm in diameter.

Advances in the surgical management of liver malignancies

Primary malignancies of the liver include tumors arising from the hepatocytes (hepatocellular carcinoma and the fibrolamellar variant) and the intrahepatic bile ducts (intrahepatic cholangiocarcinoma). Hepatocellular carcinoma is the most common primary cancer of the liver and is a leading cause of death from cancer worldwide. Although it is uncommon in the United States, the incidence of hepatocellular carcinoma is rising. Hepatitis, ethanol use, and cirrhosis often dominate the clinical picture and may dictate prognosis. New clinical and pathological staging systems have allowed for the more accurate stratification of patients to more appropriately identify patients for resection, transplantation, and percutaneous ablation therapies. A correlation between liver volume and surgical outcome has recently been demonstrated, with small liver remnant size being associated with increased morbidity. Portal vein embolization has therefore been proposed as one way to induce hypertrophy of the anticipated liver remnant before resection. Initial reports have shown that portal vein embolization decreases the incidence of postoperative complications. More recently, systemic chemotherapy and chemoembolization have been investigated as both primary and neoadjuvant therapy. Chemoimmunotherapy with 5-fluorouracil and interferon may be associated with a superior response rate in the fibrolamellar variant of hepatocellular carcinoma. Two recent randomized studies have also indicated improved survival after hepatic artery embolization in selected patients.

The emergent role of focal liver ablation techniques in the treatment of primary and secondary liver tumours

Only 20% of patients with primary or secondary liver tumours are suitable for resection because of extrahepatic disease or the anatomical distribution of their disease. These patients could be treated by ablation of the tumour, thus preserving functioning liver. This study presents a detailed review of established and experimental ablation procedures. The relative merits of each technique will be discussed and clinical data regarding the efficacy of the techniques evaluated. A literature search from 1966 to 2003 was undertaken using Medline, Pubmed and Web of Science databases. Keywords were Hepatocellular carcinoma, liver metastases, percutaneous ethanol injection, cryotherapy, microwave coagulation therapy, radiofrequency ablation, interstitial laser photocoagulation, focused high-intensity ultrasound, hot saline injection, electrolysis and acetic acid injection. Ablative techniques offer a promising therapeutic modality to treat unresectable tumours. Large-scale randomised controlled trials are required before widespread acceptance of these techniques can occur.

Minimally invasive image-guided therapies for hepatocellular carcinoma

Minimally invasive therapies are gaining increasing attention as an alternative to standard surgical therapies in the treatment of primary hepatocellular carcinoma. These include therapies administered transcatheterally (arterial embolization, intraarterial chemoinfusion, and combination chemoembolization) and percutaneously (chemical ablation with ethanol or acetic acid, and thermal ablation with radiofrequency, microwave, or laser energies). Benefits over surgical resection include the anticipated reduction in morbidity and mortality, low cost, suitability for real time image guidance, the ability to perform ablative procedures on outpatients, and the potential application in a wider spectrum of patients, including nonsurgical candidates. This review examines reported clinical success, potential complications, current limitations, and future directions of development of chemoembolization, ethanol and acetic acid instillation, and radiofrequency, microwave, and laser thermal ablation.

Chemical ablation of hepatocellular carcinoma

Chemical ablation with absolute ethanol is the most established technique of imaging-guided regional therapy for small hepatocellular carcinomas (HCCs), with long-term survival rates that rival those of surgical resection. In this article, the authors review patient selection criteria, techniques (including the one-shot approach of ethanol ablation for HCCs larger than 3 cm), complications, follow-up, and outcomes. The use of agents other than ethanol and the combination of chemical ablation with chemoembolization is also discussed.

Locoregional therapies for hepatocellular carcinoma: a critical review from the surgeon's perspective

OBJECTIVE

This article reviews the current results of various locoregional therapies for hepatocellular carcinoma (HCC), with special reference to the implications for surgeons.

SUMMARY BACKGROUND DATA

Resection or transplantation is the treatment of choice for HCC, but most patients are not suitable candidates. The past decade has witnessed the development of a variety of locoregional therapies for HCC. Surgeons are faced with the challenge of adopting these therapies in the management of patients with resectable or unresectable HCC.

METHODS

A review of relevant English-language articles was undertaken based on a Medline search from January 1990 to August 2001.

RESULTS

Retrospective studies suggested that transarterial chemoembolization is an effective treatment for inoperable HCC, but its perceived benefit for survival has not been substantiated in randomized trials, presumably because its antitumor effect is offset by its adverse effect on liver function. Nonetheless, it remains a widely used palliative treatment for HCC not amenable to resection or ablative therapies, and it also plays an important role as a treatment of postresection recurrence and as a pretransplant therapy for transplantable HCC. Better patient selection, selective segmental chemoembolization, and treatment repetition tailored to tumor response and patient tolerance may improve its benefit-risk ratio. Transarterial radiotherapy is a less available alternative that produces results similar to those of chemoembolization. Percutaneous ethanol injection has gained wide acceptance as a safe and effective treatment for HCCs 3 cm or smaller. Uncertainty in tumor necrosis limits its potential as a curative treatment, but its repeatability allows treatment of recurrence after ablation or resection of HCC that is crucial to prolongation of survival. Cryotherapy affords a better chance of cure because of predictable necrosis even for HCCs larger than 3 cm, but its use is limited by a high complication rate. There has been recent enthusiasm for heat ablation by microwave, radiofrequency, or laser, which provides predictable necrosis with a low complication rate. Preliminary data indicated that radiofrequency ablation is superior to ethanol injection in the radicality of tumor ablation. The advent of more versatile radiofrequency probes has allowed ablation of HCCs larger than 5 cm. Recent studies have suggested that combined transarterial embolization and heat ablation is a promising strategy for large HCCs. Thus far, no randomized trials comparing various thermoablative therapies have been reported. It is also uncertain whether a percutaneous route, laparoscopy, or open surgery affords the best approach for these therapies. Thermoablative therapies have been combined with resection or used to treat postresection recurrence, and they have also been used as a pretransplant therapy. However, the value of such strategies requires further evaluation.

CONCLUSIONS

Advances in locoregional therapies have led to a major breakthrough in the management of unresectable HCC, but the exact role of the various modalities needs to be defined by randomized studies. Novel thermoablative techniques provide the surgeon with an exciting opportunity to participate actively in the management of unresectable HCC. Locoregional therapies are also useful adjuncts in the management of patients with resectable or transplantable disease. Hence, surgeons must be equipped with the latest knowledge and techniques of ablative therapy to provide the most appropriate treatment for the wide spectrum of patients with HCC.

Non-surgical treatment of hepatocellular carcinoma

Primary hepatocellular cancer is a disease with a poor prognosis for which there is little consensus on treatment and a paucity of comparative trials. The coexistence of cancer with cirrhosis complicates treatment, and also confers a high risk for the development of further tumours. Surgery, either by hepatic resection or orthotopic liver transplantation, is only a feasible option in a minority of patients. This article surveys the non-surgical approaches to the treatment of hepatocellular cancers-local ablation techniques, arterial embolization with and without chemotherapy, conventional chemotherapy and hormonal modulation, and targeted and external irradiation.