Percutaneous microwave coagulation therapy for hepatocellular carcinoma located on the surface of the liver

Evaluation of the efficacy and postoperative outcomes of hydrodissection-assisted microwave ablation for subcapsular hepatocellular carcinoma and colorectal liver metastases

PURPOSE

To explore the effect of hydrodissection assisted percutaneous microwave ablation (MWA) on the primary technique efficacy (PTE) and local tumor progression (LTP) of subcapsular hepatocellular carcinoma (HCC) and colorectal liver metastases (CRLM).

METHODS

A retrospective review of 135 patients with 181 hepatic subcapsular HCC and CRLM that underwent MWA with (hydrodissection group) and without the use of hydrodissection (control group). The PTE, cumulative LTP rate, and postoperative complications were compared between the two groups.

RESULTS

Amongst the 135 patients with 181 tumors, 60 patients with 72 tumors were in the hydrodissection group and 75 patients with 109 tumors were in the control group. The PTEs were 97.2% and 85.3% in hydrodissection and control groups, respectively (P = 0.019). Multivariate analysis showed that hydrodissection significantly improved the PTE of MWA [odds ratio (OR) 0.147; 95% confidence interval (CI) 0.031-0.703; P = 0.016). Among the tumors which achieved complete response at the first (1 month) follow-up, the overall LTP rates were 8.6% (6/70) and 11.8% (11/93) in the hydrodissection and control groups, respectively. The 1- and 2-year cumulative LTP rates were 3.0% and 5.0% for the hydrodissection group and 6.8% and 13.5% in the control group, respectively (P = 0.391). No significant differences were observed in major postoperative complications between the two groups.

CONCLUSION

Hydrodissection-assisted MWA had a significantly higher PTE than MWA alone in hepatic subcapsular HCC and CRLM. Hydrodissection did not significantly impact the cumulative LTP rate or the incidence of postoperative complications.

Evaluation of antitumour activity of tea carbohydrate polymers in hepatocellular carcinoma animals

Box-Behnken design criterion was applied to identify the significant effects of various extraction parameters such as temperature, time, and solvent-solid ratio on extraction of tea carbohydrate. Among the three variables tested extraction temperature, and solvent-solid ratio were found to have significant effect on tea carbohydrate extraction. The most suitable condition for extraction of tea carbohydrate was found to be a single step extraction at extraction temperature 90°C, extraction time 30 min, and solvent-solid ratio 5:1. At these optimum extraction parameters, the maximum yield of tea carbohydrate obtained experimentally was found to be very close to its predicted value of 3.47% dry weight of root. Then, we have studied the influence of tea carbohydrate on biochemical parameters in hepatocellular carcinoma (HCC) animals. Hepatocellular carcinoma was induced by the injection of 1×10(5) H22 hepatocarcinoma cells into right hind thigh muscle in experimental animals. Tea carbohydrate could inhibit tumour growth and decrease microvessel density in tumour tissue. The altered amount of serum white blood cells (WBC), Interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) in HCC animals were dose-dependently increased, whereas activities of serum alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) were dose-dependently decreased in the drug treated animals. In addition, tea carbohydrate administration could decrease expression of vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (PCNA) in H22 tumor tissue. It can be concluded that tea carbohydrate displayed strong antitumour activity in animals.

Thermal ablative therapies for secondary hepatic malignancies

Hepatic metastatic disease affects more than half of the patients with colorectal cancer and neuroendocrine cancer. Hepatic resection remains the gold standard for liver metastasis from colorectal and neuroendocrine primaries. Thermal ablative technologies, however, are increasingly being used either alone or in combination with resection to treat this group of patients. Radiofrequency ablation is the most common modality used in the United States, whereas microwave ablation has been more widely used in the East. In addition to being adjuncts to hepatic resection, ablation has gained an increased popularity in the management of patients who are not operative candidates or have unresectable colorectal or neuroendocrine hepatic metastasis. Although radiofrequency ablation seems to have a higher local recurrence than resection, ablation remains an important therapeutic option for many patients with hepatic metastasis.

Percutaneous radiofrequency ablation for the hepatocellular carcinoma abutting the diaphragm: assessment of safety and therapeutic efficacy

Objective

To assess the safety and therapeutic efficacy of a percutaneous radiofrequency (RF) ablation for the hepatocellular carcinoma (HCC) abutting the diaphragm.

Materials and Methods

We retrospectively assessed 80 patients who underwent a percutaneous RF ablation for a single nodular (< 4 cm) HCC over the last four years. Each patient underwent an ultrasound-guided RF ablation using internally cooled electrodes for the first-line treatment. We divided patients into two subgroups based on whether the index tumor was abutting (less than 5 mm) the diaphragm or not: group A (abutting; n = 31) versus group B (non-abutting; n = 49). We compared the two subgroups for complications and therapeutic efficacy using image and the review of medical records. The statistical assessment included an independent t-test, Fisher's exact test, and chi-square test.

Results

The assessment of the diaphragmatic swelling at CT immediately following the procedure was more severe in group A than group B (mean thickness change:1.44 vs. 0.46 mm, p = 0.00). Further, right shoulder pain was more common in group A than B (p = 0.01). Although minor complications (hemothorax 1 case, pleural effusion 1 case) were noted only in group A, no major thoracic complication occurred in either group. The technical success rate was lower in group A than group B (84% vs. 98%, p = 0.03). As well, the primary and secondary technique effectiveness rates in group A and group B were 90% versus 98% (p = 0.29) and 79% versus 91% (p = 0.25), respectively. The local tumor progression rate was higher in group A than in group B (29% vs. 6%, p = 0.02).

Conclusion

We found that the percutaneous RF ablation for the HCC abutting the diaphragm is a safe procedure without major complications. However, it is less effective with regard to technical success and local tumor control.

Effect of artificial ascites on thermal injury to the diaphragm and stomach in radiofrequency ablation of the liver: experimental study with a porcine model

OBJECTIVE

The purpose of this study was to evaluate the effect of artificial ascites on thermal injury to the diaphragm and stomach in a porcine model of radiofrequency ablation of the liver.

MATERIALS AND METHODS

We performed this study using eight pigs in experimental and control groups of four pigs each. Artificial ascites was produced before radiofrequency ablation to separate the liver from the diaphragm and the stomach in the experimental group. Using a 1-cm exposed internally cooled radiofrequency electrode for 5 minutes, we performed 74 hepatic ablations abutting the diaphragm and stomach. CT was performed on the day of the procedure and 7 days after ablation. The pigs were sacrificed, and necropsy was performed. We performed pathologic and CT examinations to compare the frequency and extent of thermal injury to the two organs.

RESULTS

The mean number of radiofrequency ablations in each pig was 9.3 (range, 6-12). The mean number of ablation zones adjoining the diaphragm was 5.5 (range, 3-8) and of zones contiguous with the stomach was 3.8 (range, 3-4). Thermal injury to the adjacent organs occurred more frequently in the control group than in the experimental group (p < 0.05). The major complications of diaphragmatic hernia and gastric perforation occurred only in the control group. No major complications were identified in the experimental group at necropsy. The sizes of the radiofrequency ablation zone of the liver did not differ between the two groups (p > 0.05). The mean diameters of the diaphragmatic and gastric lesions did differ (p < 0.05). Histopathologic examination revealed a significant difference in the depths of thermal injury in the two groups (p < 0.05).

CONCLUSION

Artificial ascites may be a simple and useful technique for reducing the frequency and severity of collateral thermal injury to the diaphragm and stomach during radiofrequency ablation of subcapsular hepatic tumors.

Combined radiofrequency ablation and doxorubicin-eluting polymer implants for liver cancer treatment

Previously, biodegradable polymer implants (polymer millirods) to release chemotherapeutic agents directly into tumors have been developed. The purpose of this study is to evaluate local drug distribution from these implants in liver tumors treated with radiofrequency (RF) ablation and determine if the implants provide a therapeutic improvement over RF ablation alone. Cylindrical implants were fabricated using 65% poly(D,L-lactide-co-glycolide) (PLGA), 21.5% NaCl, and 13.5% doxorubicin. Control or drug-containing millirods were implanted inside VX2 liver tumors (11 mm diameter) in rabbits after RF ablation. Therapeutic efficacy was assessed 4 and 8 days after treatment using tumor size, histology, and fluorescence measurement of drug distribution. Tumors in both test groups recurred at the boundary of the ablated region. Therapeutic doxorubicin concentrations were found in more than 80% of the ablated area, but concentrations declined rapidly at the boundary between normal and ablated tissue. This region was characterized by a developing fibrous capsule with resolving inflammation, which restricted drug transport out of the ablated zone. The intratumoral doxorubicin implants delivered high concentrations of drug within the ablated region but only limited amounts outside the ablation zone. Future studies will focus on overcoming the fibrotic transport barrier and enhancing drug delivery to the periphery of the ablation region to prevent tumor progression.

Activating anti-CD40 antibodies induce tumour invasion by cytotoxic T-lymphocytes and inhibition of tumour growth in experimental liver cancer

The aim of this study was to investigate the effects of an activating anti-CD40 antibody (aCD40Ab) on leukocyte adhesion to tumour vessels, leukocyte migration and tumour growth in experimental liver cancer. Morris-Hepatoma was induced by subcapsular inoculation of tumour cells in the liver of ACI-rats. On day 7 and 8 after tumour cell injection, one group of the animals received aCD40Ab. On day 13 the tumour volume was measured and intravital microscopy was performed quantifying leukocyte adherence in the liver. Furthermore, immunohistological analyses were performed. aCD40Ab-Treated animals showed increased leukocyte-endothelium interaction, demonstrated substantially more T- and natural killer (NK) cells in the tumour and had a distinctly decreased tumour volume. Our results show that treatment with aCD40Ab stimulates endothelial leukocyte adhesion in tumour vessels and migration of CD4 cells/CD8 T-cells and NK cells into the tumour and inhibits tumour growth. Thus, the CD40/CD154 pathway is a worthwhile target for adjuvant immunotherapy.

Right trisectionectomy for primary liver cancer

AIM: To evaluate the value of right trisectionectomy, previously named right trisegmentectomy, in the treatment of primary liver cancer by summarizing our 13-year experience for this procedure.

METHODS: Thirty three primary liver cancer patients undergoing right trisectionectomy from Apr. 1987 to Dec. 1999 were investigated retrospectively. The impacts in survival of patients by cancerous biological behavior, such as tumor thrombi and satellite nodules, were discussed respectively. All right trisectionectomies were performed under normothermic interruption of porta hepatis at single time. Ultrasonic dissector (CUSA system 200) was used in dissection of hepatic parenchyma from Nov. 1992, instead of finger fracture.

RESULTS: 1-, 3- and 5-year survival rates were 71.9%, 40.6% and 34.4%, respectively. The longest survival term with free cancer was 150 months (alive). There were no significant differences in survival curves between cases with and without tumor thrombi (right branch of portal vein) and satellite nodules. Operative mortality was 3.0% (1/33). Main surgical complications occurred in 5 cases.

CONCLUSION: Right trisectionectomy should be regarded as an effective and safe procedure for huge primary liver cancers and is worth using more widely.

Right trisectionectomy for primary liver cancer

AIM

To evaluate the value of right trisectionectomy, previously named right trisegmentectomy, in the treatment of primary liver cancer by summarizing our 13-year experience for this procedure.

METHODS

Thirty three primary liver cancer patients undergoing right trisectionectomy from Apr. 1987 to Dec. 1999 were investigated retrospectively. The impacts in survival of patients by cancerous biological behavior, such as tumor thrombi and satellite nodules, were discussed respectively. All right trisectionectomies were performed under normothermic interruption of porta hepatis at single time. Ultrasonic dissector (CUSA system 200) was used in dissection of hepatic parenchyma from Nov. 1992, instead of finger fracture.

RESULTS

1-, 3- and 5-year survival rates were 71.9 %, 40.6 % and 34.4 %, respectively. The longest survival term with free cancer was 150 months (alive). There were no significant differences in survival curves between cases with and without tumor thrombi (right branch of portal vein) and satellite nodules. Operative mortality was 3.0 % (1/33). Main surgical complications occurred in 5 cases.

CONCLUSION

Right trisectionectomy should be regarded as an effective and safe procedure for huge primary liver cancers and is worth using more widely.

Effects of intraaterial chemoembolization combined with percutaneous microwave coagulation on hepatocellular carcinoma: a clinical and experimental study

AIM: To evaluate the role of microwave coagulation for liver cancer after occlusion of hepatic artery in animal experiment and clinical study.

METHODS: Total 24 suitable hepatic lobes of ten dogs were separated into two groups. Microwave coagulation alone (control group) or after hepatic artery occlusion (experiment group) was performed respectively. The power of irradiation was 50 W and the duration was 300 and 400 seconds. Clinically, 25 patients with hepatocellular carcinoma (30 nodules) were treated with PMCT after TACE. The TACE was performed 1-3 times and PMCT 1-2 times totally in every patients.

RESULTS: In animal experiment, the coagulated area was elliptic in control group and was elliptic or round in experimental group. The volume of coagulated tissue in experimental group was 3.8 times bigger than that in control. Clinically, all the lesions in contrast-enhanced CT showed slight enhancement or no enhancement after treatment. Intratumoral blood flow decreased significantly in 6 patients and disappeared in 20 patients. In 19 patients with elevated a-fetoprotein, the level decreased in all patients and was normalized in 14. There were no significant side- effects.

CONCLUSION: PMCT after TACE can significantly enlarge the necrosis volume of microwave coagulation, and promote the efficacy of treatment for hepatocellular carcinoma.

New nonsurgical therapies in the treatment of hepatocellular carcinoma

The last decade has seen a rapid increase in the incidence of hepatocellular carcinoma in the United States, mostly because of the increased incidence of hepatitis C. Surgical therapy remains limited to the few patients who are surgical candidates at presentation. In addition, surgery has been plagued by high recurrence rates, which can reach 80% at 3 years. Systemic chemotherapy has been found to be ineffective, with response rates approaching 10% to 20%. Nonsurgical percutaneous therapies, including percutaneous locoregional ablative procedures (ethanol or acetic acid injection, radiofrequency ablation, microwave coagulation therapy, chemotherapy infusion, laser photocoagulation, and high-intensity ultrasound) and intra-arterial procedures (radioembolization with yttrium-90 microspheres or transcatheter intra-arterial chemoembolization) are gaining popularity because they are less invasive than surgery and can be nearly as effective in prolonging survival. Multiple studies have shown good response rates with high technical success rates, as well as significant survival advantages for nonresectable disease. Furthermore, they can be performed repeatedly without compromising liver function and at a considerably lower morbidity and cost than surgery.

Hepatocellular carcinoma--cause, treatment and metastasis

In the recent decades, the incidence of hepatocellular carcinoma (HCC) has been found to be increasing in males in some countries. In China, HCC ranked second of cancer mortality since 1990s. Hepatitis B and C viruses (HBV and HCV) and dietary aflatoxin intake remain the major causative factors of HCC. Surgery plays a major role in the treatment of HCC, particularly for small HCC. Down-staging unresectable huge HCC to smaller HCC and followed by resection will probably be a new approach for further study. Liver transplantation is indicated for small HCC, however, some issues remain to be solved. Different modes of regional cancer therapy for HCC have been tried. Systemic chemotherapy has been disappointing in the past but the future can be promising. Biotherapy, such as cytokines, differentiation inducers, anti-angiogenic agents, gene therapy and tumor vaccine will probably play a role, particularly in the prevention of tumor recurrence. HCC invasiveness is currently the major target of study. Tremendous works have been done at the molecular level, which will provide clues for biomarker of HCC progression as well as targets for intervention.

CT appearance of hepatic parenchymal changes after percutaneous microwave coagulation therapy for hepatocellular carcinoma

PURPOSE

The purpose of this study was to evaluate the changes in the CT appearance of the hepatic parenchyma surrounding the necrotic area in the early period after percutaneous microwave coagulation therapy (PMCT) for hepatocellular carcinoma (HCC).

METHOD

We reviewed enhanced CT scans obtained before and within 2 weeks, at 1 month, and at 3 months after PMCT of 61 lesions in 47 patients with HCC.

RESULTS

On dynamic CT, early enhancement of the hepatic parenchyma around the treated area was a frequent finding within 1 (87%) or 2 (68%) weeks after PMCT, but such enhancement disappeared on follow-up. Arterioportal shunts were also demonstrated by enhanced CT after treatment (21% at < or =2 weeks), and these shunts tended to persist for >1 month.

CONCLUSION

We should evaluate the effect of PMCT by performing dynamic enhanced CT not only within 2 weeks to determine the end-point of treatment but also at 1 month or more after finishing treatment for definite assessment of tumor necrosis.