Irrigation of the Bile Ducts with Chilled Saline During Percutaneous Radiofrequency Ablation of a Hepatic Ocular Melanoma Metastasis

Safety and efficacy of microwave ablation for periductal hepatocellular carcinoma with intraductal cooling of the central bile ducts through a percutaneous transhepatic cholangial drainage tube

Background and aims

Methods

Results

Conclusions

Management of uveal melanoma: a consensus-based provincial clinical practice guideline

INTRODUCTION

Survival in uveal melanoma has remained unchanged since the early 1970s. Because outcomes are highly related to the size of the tumour, timely and accurate diagnosis can increase the chance for cure.

METHODS

A consensus-based guideline was developed to inform practitioners. PubMed was searched for publications related to this topic. Reference lists of key publications were hand-searched. The National Guidelines Clearinghouse and individual guideline organizations were searched for relevant guidelines. Consensus discussions by a group of content experts from medical, radiation, and surgical oncology were used to formulate the recommendations.

RESULTS

Eighty-four publications, including five existing guidelines, formed the evidence base.

SUMMARY

Key recommendations highlight that, for uveal melanoma and its indeterminate melanocytic lesions in the uveal tract, management is complex and requires experienced specialists with training in ophthalmologic oncology. Staging examinations include serum and radiologic investigations. Large lesions are still most often treated with enucleation, and yet radiotherapy is the most common treatment for tumours that qualify. Adjuvant therapy has yet to demonstrate efficacy in reducing the risk of metastasis, and no systemic therapy clearly improves outcomes in metastatic disease. Where available, enrolment in clinical trials is encouraged for patients with metastatic disease. Highly selected patients might benefit from surgical resection of liver metastases.

Locoregional management of hepatic metastasis from primary uveal melanoma

Uveal melanoma is the most common primary ocular malignancy in adults and has a significant predilection for metastasis to the liver. Despite successful treatment of the primary uveal melanoma, up to 50% of patients will subsequently develop a systemic metastasis, with the liver involved in up to 90% of these individuals. Metastatic uveal melanoma has proven to be resistant to currently available systemic chemotherapies. Recognition of the poor prognosis associated with liver metastasis has led to the evaluation of various locoregional treatment modalities primarily designed to control tumor progression in the liver, including surgical resection, hepatic arterial chemotherapy, transarterial chemoembolization (TACE), immunoembolization, radiosphere, drug-eluting beads, isolated hepatic perfusion (IHP), and percutaneous hepatic perfusion. This article reviews the efficacies, and morbidities of currently available locoregional therapies.

Intraductal chilled saline perfusion to prevent bile duct injury during percutaneous radiofrequency ablation for hepatocellular carcinoma

BACKGROUND AND AIM

Radiofrequency ablation (RFA) is a promising, minimally invasive treatment for hepatocellular carcinoma (HCC). However, thermal injury sometimes occurs in the bile duct, potentially leading to a critical situation. The aim of the present study was to investigate whether bile duct injury is reduced by an intraductal chilled saline perfusion (ICSP) through a nasobiliary tube during RFA for HCC.

PATIENTS AND METHODS

The baseline incidence of bile duct injury at Gifu Municipal Hospital was 3.1% (13 patients) in 424 patients with HCC treated by percutaneous RFA. In all patients, the tumor was within 5 mm of the central bile duct on CT images. The incidence of bile duct injury was 46% among the 28 selected patients whose tumor was close to the central bile duct. To prevent complications in such high-risk patients, we placed a nasobiliary tube endoscopically before RFA, and performed ICSP during RFA. Forty consecutive patients with tumors close to the central bile duct were enrolled in this study.

RESULTS

Of the 40 enrolled patients, only one had biliary injury, whereas the remaining 39 patients were able to avoid it. The incidence of biliary injury was significantly reduced in the ICSP group (1/40, 2.5%) compared to that in the control group (13/28, 46%) (P < 0.0001). Moreover, the liver function 6 months after RFA was also better preserved in the ICSP group according to Child-Pugh grading, thus resulting in a better clinical outcome.

CONCLUSIONS

ICSP through a nasobiliary tube is a potential intervention method to prevent biliary injury by percutaneous RFA.

The safety and efficacy of radiofrequency and electrolytic ablation created adjacent to large hepatic veins in a porcine model

INTRODUCTION

Immediately adjacent to large hepatic veins, tumour ablation by radiofrequency or electrolysis may be impaired by heat or current sink effects. Ablation may also cause vessel injury and thrombosis. The aim of this study was to evaluate the safety and efficacy of radiofrequency and electrolytic ablative techniques adjacent to large hepatic veins.

METHODS

Electrolytic and radiofrequency zones of ablation were created adjacent to hepatic veins in large white pigs. After 72 h the zones of ablation created were examined histologically for (a) the extent of tissue necrosis up to the vessel and (b) the presence of intimal damage and mural thrombus in the veins.

RESULTS

An unexpected complication of electrolysis near large veins was cardiac tamponade. This current related phenomenon could easily be avoided. In seven of nine electrolysis zones of ablation necrosis was completely adjacent to the vessel wall, but in only four of seven radiofrequency zones of ablation. All zones of ablation were associated with intimal necrosis, and most with mural thrombosis.

CONCLUSIONS

Ablation of hepatic tumours by radiofrequency and electrolysis is unreliable adjacent to hepatic veins. Both techniques are associated with mural thrombus formation, and so risk thrombo-embolic complication. These ablative modalities are not recommended for zones of ablation adjacent to hepatic veins.

Magnetic resonance imaging for hepatic radiofrequency ablation

Image-guided radiofrequency (RF) ablation is a minimally invasive therapy option in the treatment of primary and secondary hepatic malignancies. Magnetic resonance (MR) imaging offers an accurate pre-interventional imaging having important impact on patient selection and planning of the ablation procedure. Peri-interventional imaging is used for targeting, monitoring, and controlling of the ablation procedure. Due to a high soft-tissue contrast offering delineation of tumor tissue and the surrounding anatomy, coupled with multiplanar capabilities, MR imaging is an advantageous targeting technique compared with ultrasonography (US) or computed tomography (CT). MR imaging is sensitive to thermal effects enabling a monitoring of ablation therapy subsequently being supportive to control the ablation procedure. Therefore, MR imaging can fulfil the conditions for overlapping ablations by enabling a precise repositioning of the MR compatible RF applicator if required. Thus, the probability of achieving complete coagulation in larger tumors within a single therapy session is potentially increased. A monitoring of thermal effects is moreover essential in order to prevent unintended tissue damage from critical structures in the surrounding of the target tissue. Post-interventional imaging is performed to assess treatment response after RF ablation and has prognostic impact, as an early detection of treatment failure, e.g. residual tumor tissue, enables immediate therapy. Nevertheless, differential diagnostic difficulties arise from benign periablational enhancement which may cover tumor tissue. Hence, further evaluation and improvement in the assessment of treatment response is essential.

Radiofrequency Ablation of Metastatic Mediastinal Lymph Nodes during Cooling and Temperature Monitoring of the Tracheal Mucosa to Prevent Thermal Tracheal Damage: Initial Experience

Institutional review board approval and patient informed consent were obtained. Radiofrequency ablation in a total of 10 sessions was performed for each mediastinal lymph node metastasis from esophageal cancer that had a mean largest diameter of 2.2 cm +/- 0.6 (standard deviation) in seven male patients (mean age, 59 years). During ablation, cooling and temperature of the tracheal mucosa were monitored in the proper position in eight of the 10 sessions; in the other two sessions, monitoring was not done because of tracheal stenosis (perforation resulted). Three of the four lymph nodes that were 2.0 cm or smaller in largest diameter showed no evidence of local progression for at least 1 year since ablation; all three of the nodes greater than 2.0 cm in largest diameter progressed within 6 months. The 1-year survival rate was 60%; the median survival time was 13 months. Radiofrequency ablation may be effective for local control of small metastatic mediastinal lymph nodes, and cooling and temperature monitoring of the tracheal mucosa in the proper position may prevent thermal tracheal damage.