Radiofrequency ablation of the pancreas: protective effect of local cooling techniques (original) (raw)

Radiofrequency ablation of the pancreas. I: Definition of optimal thermal kinetic parameters and the effect of simulated portal venous circulation in an ex-vivo porcine model

JOP : Journal of the pancreas, 2005

Radiofrequency ablation of pancreatic tumours carries a risk of injury to important structures such as the bile duct and duodenum. We have recently developed an ex-vivo model of radiofrequency ablation of the porcine pancreas. This study evaluates the effect of variations in probe temperature, duration of ablation and simulated portal venous flow on radiofrequency-induced injury. SPECIMEN RETRIEVAL: Pancreata of 30 6-month-old healthy pigs undergoing sacrifice in a commercial abattoir were used. Radiofrequency energy was applied to a pre-marked area of the pancreatic head. Pancreatic head biopsies were taken after ablation to incorporate duodenum, portal vein and bile duct respectively and frozen in liquid nitrogen. For each experiment a portion of the tail of the pancreas was studied as non-ablated control. Paired slides using haematoxylin and eosin (H&E) and nicotinamide adenine dinucleotide (NADH) stains were prepared. The effects of variation in target temperature (100 degrees C...

Endoscopic Ultrasound-Guided Radiofrequency Ablation (EUS-RFA) of the Pancreas in a Porcine Model

Gastroenterology Research and Practice, 2012

Backgrounds. Limited effective palliative treatments exist for pancreatic cancer which includes surgery or chemotherapy. Radiofrequency ablation (RFA) uses high frequency alternating current to ablate diseased tissue and has been used to treat various tumors. In this study, we evaluated a prototype probe adjusted to the EUS-needle to perform EUS-RFA to permit coagulative necrosis in the pancreas. Methods. Five Yucatan pigs underwent EUS-guided radiofrequency ablation of the head of their pancreas. Using an EUS-needle, RFA was applied with 6 mm and then 10 mm of the probe exposed at specific wattage for preset durations. Results. Only one pig showed moderate levels of pancreatitis (20% proximal pancreatitis). The other animals showed much lower areas of tissue damage. In 3 of the 5 pigs, the proximal pancreas showed greater levels of tissue injury than the distal pancreas, consistent with the proximity of the tissue to the procedure site. In 1 pig, both proximal and distal pancreas showed minimal pancreatitis (1%). There was minimal evidence of fat necrosis in intra-pancreatic and/or extra-pancreatic adipose tissue. Conclusion. EUS-guided RFA of the pancreatic head with the monopolar probe through a 19-gauge needle was well tolerated in 5 Yucatan pigs and with minimal amount of pancreatitis.

Radiofrequency pancreatic ablation and section of the main pancreatic duct does not lead to necrotizing pancreatitis

Pancreas, 2014

The aim of this study was to determine whether radiofrequency ablation (RFA) of the pancreas and subsequent transection of the main pancreatic duct may avoid the risk of both necrotizing pancreatitis and postoperative pancreatic fistula (POPF) formation. Thirty-two rats were subjected to RFA and section of the pancreas over their portal vein. Animals were killed at 3, 7, 15, and 21 days (groups 0-3, respectively). Two additional control groups (sham operation and user manipulation only, respectively) of 15 days of postoperative period were considered. Postoperative complications, histological changes (including morphometric and immunohistochemical analysis), and incidence of POPF were evaluated. A significant increase in serum amylase levels (P < 0.05) on the third postoperative day, which return to baseline levels in the following weeks, was noted in groups 0 to 3. Those groups showed a rapid atrophy of the distal pancreas by apoptosis with no signs of necrotizing pancreatitis o...

Healing dynamics of porcine pancreatic parenchyma after radiofrequency ablation - in vivo experimental pilot study

Acta Veterinaria Brno, 2012

Radiofrequency ablation is a tumour destruction method, widely used in human as well veterinary medicine. Recently, it has been applied to pancreatic disorder treatment. However, little is known about healing of the pancreatic parenchyma after radiofrequency ablation as it is important for the prevention of complications and treatment strategy. The aim of this experimental in vivo study on pigs was to evaluate the pancreatic parenchyma healing dynamics after damage by radiofrequency ablation. Radiofrequency ablations of the duodenal lobe of the pancreas were performed on 8 cross-bred laboratory pigs. They were euthanized in pairs at seven, fourteen, forty and eighty days after the procedure. Histological and cytological changes of the ablated zone were evaluated after autopsy. It was proved that pancreatic necrosis after radiofrequency ablation heals by means of fibrotic scar. There was no sign of exocrine and endocrine regeneration, respectively, during 80 days after the procedure. This is the first study verifying that the healing process of an ablation zone in the pancreatic parenchyma after radiofrequency ablation is similar to healing in the liver, lung, heart and other parenchymal organs.

Decreasing Pancreatic Leak After Distal Pancreatectomy: Saline-coupled Radiofrequency Ablation in a Porcine Model

Journal of Gastrointestinal Surgery, 2007

Despite marked improvements in pancreatic surgery, the high incidence and morbidity of pancreatic leak after resection has remained unchanged. The objective of this study was to evaluate the role of saline-coupled radiofrequency ablation (TissueLink) as an alternative to traditional methods of stump closure in an animal model of distal pancreatectomy. Forty swine were randomized after pancreatic transection and remnant stump was either oversewn in a traditional fashion (control) or treated with the device alone (TissueLink). Animals were killed and necropsied at 3 or 5 weeks postoperatively. Primary endpoints were the development of a pancreatic fistula defined as dye extravasation from the remnant duct, presence of undrained amylase-rich fluid collections/abscess, and greater than threefold drain/serum amylase after the third postoperative day. The incidence of pancreatic leak in the TissueLink group was 5.5 vs 42% in the control group (p=0.01). There were no differences in operative time or other clinical parameters measured. Histologic analysis of the remnant pancreatic stumps confirmed our results. These data support our hypothesis that saline-coupled radiofrequency ablation leads to obliteration of ducts with a resultant decrease in pancreatic leak and subsequent complications. This technology may play a substantial role in preventing this dreaded complication in the clinical setting.

Radiofrequency ablation combined with palliative surgery may prolong survival of patients with advanced cancer of the pancreas

Langenbeck's Archives of Surgery, 2006

Background and aim The aim of this study is to identify the benefit acquired by the use of radiofrequency ablation in parallel to palliative therapy in patients with advanced cancer of the pancreas. Materials and methods Data on 25 consecutive patients who underwent palliative therapy with or without radiofrequency ablation for unresectable pancreatic cancer were included in this retrospective review. Thirteen patients received palliative therapy alone, whereas 12 patients received palliative therapy plus radiofrequency ablation. Results Overall mean survival rate in patients receiving paliative therapy alone was 13 months and the maximum survival was 30 months. Where radiofrequency ablation was applied, mean survival was estimated at 33 months (p=0.0048). Stage III and IV patients treated with palliative therapy alone have a mean survival of 15 and 10 months, respectively. All stage III patients receiving radiofrequency ablation are alive at present and maximum survival has reached 38 months (p=0.0032), whereas stage IV patients who were treated with radiofrequency ablation have an estimated mean survival period of 14 months (p=0.1095). Conclusion Radiofrequency ablation in parallel to palliative therapy seems to provide survival benefit especially for stage III patients with unresectable pancreatic cancer. Further studies should be conducted to determine the usefulness of radiofrequency ablation in the treatment of advanced pancreatic cancer.