Radiofrequency ablation of the pancreas with and without intraluminal duodenal cooling in a porcine model. J Surg Res. 2013;184:867-872. [PMID: 23726235 DOI: 10.1016/j.jss.2013.04.068]

Endoscopic Ultrasound-Guided Radiofrequency Ablation (EUS-RFA) for Pancreatic Adenocarcinoma: A Review

Pancreatic ductal adenocarcinoma (PDAC) is still one of the deadliest neoplasms in the world. Although various advancements in the treatment and management of this disease have been made, no significant overall survival benefit has been achieved. Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has been proposed as a treatment for patients who are unfit for surgery or with inoperable PDAC. We conducted a literature review of the PubMed and Embase databases to identify and analyze studies on the use of EUS-RFA in inoperable PDAC. Eleven studies with a total of 122 patients were analyzed to assess the population characteristics, feasibility and safety of the procedure, and overall survival of the population. Technical success was achieved in 95.1% of cases, and no intraoperative complications were reported. The most common early complication reported was abdominal pain (21 out of 122 patients) with a total early complication rate of 29.6%, and none of these complications affected hospital stays or post-procedure recovery. Late complications were reported in four patients (3.2%). Post-procedure cytoreduction was achieved in all patients, although disease progression was reported in 119 of 122 patients. The overall survival rate did not differ from that reported in the literature. We found that EUS-RFA could be a valid palliative option for inoperable patients, a bridge for surgery reducing the size of the tumor and its vascular relationship, or a first-line therapy in a subset of selected patients. Larger cohort and prospective studies should be conducted to establish guidelines for this procedure.

Proactive esophageal cooling during laser cardiac ablation: A computer modeling study

BACKGROUND AND OBJECTIVES

Laser ablation is increasingly used to treat atrial fibrillation (AF). However, atrioesophageal injury remains a potentially serious complication. While proactive esophageal cooling (PEC) reduces esophageal injury during radiofrequency ablation, the effects of PEC during laser ablation have not previously been determined. We aimed to evaluate the protective effects of PEC during laser ablation of AF by means of a theoretical study based on computer modeling.

METHODS

Three-dimensional mathematical models were built for 20 different cases including a fragment of atrial wall (myocardium), epicardial fat (adipose tissue), connective tissue, and esophageal wall. The esophagus was considered with and without PEC. Laser-tissue interaction was modeled using Beer-Lambert's law, Pennes' Bioheat equation was used to compute the resultant heating, and the Arrhenius equation was used to estimate the fraction of tissue damage (FOD), assuming a threshold of 63% to assess induced necrosis. We modeled laser irradiation power of 8.5 W over 20 s. Thermal simulations extended up to 250 s to account for thermal latency.

RESULTS

PEC significantly altered the temperature distribution around the cooling device, resulting in lower temperatures (around 22°C less in the esophagus and 9°C in the atrial wall) compared to the case without PEC. This thermal reduction translated into the absence of transmural lesions in the esophagus. The esophagus was thermally damaged only in the cases without PEC and with a distance equal to or shorter than 3.5 mm between the esophagus and endocardium (inner boundary of the atrial wall). Furthermore, PEC demonstrated minimal impact on the lesion created across the atrial wall, either in terms of maximum temperature or FOD.

CONCLUSIONS

PEC reduces the potential for esophageal injury without degrading the intended cardiac lesions for a variety of different tissue thicknesses. Thermal latency may influence lesion formation during laser ablation and may play a part in any collateral damage.

The Assessment of a Novel Endoscopic Ultrasound-Compatible Cryocatheter to Ablate Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease that may be treated utilizing thermal therapies. Cryoablation is an effective, minimally invasive therapy that has been utilized for the treatment of various cancers, offering patients a quicker recovery and reduced side effects. Cryoablation has been utilized on a limited basis for the treatment of PDAC. With the recent reports on the success of cryoablation, there is a growing interest in the use of cryoablation as a standalone, minimally invasive procedure to treat PDAC. While offering a promising path, the application of cryoablation to PDAC is limited by current technologies. As such, there is a need for the development of new devices to support advanced treatment strategies for PDAC. To this end, this study investigated the performance of a new endoscopic ultrasound-compatible cryoablation catheter technology, FrostBite. We hypothesized that FrostBite would enable the rapid, effective, minimally invasive delivery of ultra-cold temperatures to target tissues, resulting in effective ablation via an endoscopic approach. Thermal properties and ablative efficacy were evaluated using a heat-loaded gel model, tissue-engineered models (TEMs), and an initial in vivo porcine study. Freeze protocols evaluated included single and repeat 3 and 5 min applications. Isotherm assessment revealed the generation of a 2.2 cm diameter frozen mass with the -20 °C isotherm reaching a diameter of 1.5 cm following a single 5 min freeze. TEM studies revealed the achievement of temperatures ≤ -20 °C at a diameter of 1.9 cm after a 5 min freeze. Fluorescent imaging conducted 24 h post-thaw demonstrated a uniformly shaped ellipsoidal ablative zone with a midline diameter of 2.5 cm, resulting in a total ablative volume of 6.9 cm3 after a single 5 min freeze. In vivo findings consistently demonstrated the generation of ablative areas measuring 2.03 cm × 3.2 cm. These studies demonstrate the potential of the FrostBite cryocatheter as an endoscopic ultrasound-based treatment option. The data suggest that FrostBite may provide for the rapid, effective, controllable freezing of cancerous pancreatic and liver tissues. This ablative power also offers the potential of improved safety margins via the minimally invasive nature of an endoscopic ultrasound-based approach or natural orifice transluminal endoscopic surgery (NOTES)-based approach. The results of this pre-clinical feasibility study show promise, affirming the need for further investigation into the potential of the FrostBite cryocatheter as an advanced, minimally invasive cryoablative technology.

Interventional gastroenterology in oncology

Cancer is one of the foremost health problems worldwide and is among the leading causes of death in the United States. Gastrointestinal tract cancers account for almost one third of the cancer-related mortality globally, making it one of the deadliest groups of cancers. Early diagnosis and prompt management are key to preventing cancer-related morbidity and mortality. With advancements in technology and endoscopic techniques, endoscopy has become the core in diagnosis and management of gastrointestinal tract cancers. In this extensive review, the authors discuss the role endoscopy plays in early detection, diagnosis, and management of esophageal, gastric, colorectal, pancreatic, ampullary, biliary tract, and small intestinal cancers.

An In Vitro Investigation into Cryoablation and Adjunctive Cryoablation/Chemotherapy Combination Therapy for the Treatment of Pancreatic Cancer Using the PANC-1 Cell Line

As the incidence of pancreatic ductal adenocarcinoma (PDAC) continues to grow, so does the need for new strategies for treatment. One such area being evaluated is cryoablation. While promising, studies remain limited and questions surrounding basic dosing (minimal lethal temperature) coupled with technological issues associated with accessing PDAC tumors and tumor proximity to vasculature and bile ducts, among others, have limited the use of cryoablation. Additionally, as chemotherapy remains the first-line of attack for PDAC, there is limited information on the impact of combining freezing with chemotherapy. As such, this study investigated the in vitro response of a PDAC cell line to freezing, chemotherapy, and the combination of chemotherapy pre-treatment and freezing. PANC-1 cells and PANC-1 tumor models were exposed to cryoablation (freezing insult) and compared to non-frozen controls. Additionally, PANC-1 cells were exposed to varying sub-clinical doses of gemcitabine or oxaliplatin alone and in combination with freezing. The results show that freezing to −10 °C did not affect viability, whereas −15 °C and −20 °C resulted in a reduction in 1 day post-freeze viability to 85% and 20%, respectively, though both recovered to controls by day 7. A complete cell loss was found following a single freeze below −25 °C. The combination of 100 nM gemcitabine (1.1 mg/m2) pre-treatment and a single freeze at −15 °C resulted in near-complete cell death (<5% survival) over the 7-day assessment interval. The combination of 8.8 µM oxaliplatin (130 mg/m2) pre-treatment and a single −15 °C freeze resulted in a similar trend of increased PANC-1 cell death. In summary, these in vitro results suggest that freezing alone to temperatures in the range of −25 °C results in a high degree of PDAC destruction. Further, the data support a potential combinatorial chemo/cryo-therapeutic strategy for the treatment of PDAC. These results suggest that a reduction in chemotherapeutic dose may be possible when offered in combination with freezing for the treatment of PDAC.

Role of radio-ablative technique for optimizing the survival of patients with locally advanced pancreatic adenocarcinoma (Review)

Pancreatic ductal adenocarcinoma (PDAC) is one of the most common and frequently diagnosed malignant tumor of the pancreas with few treatment options and poor life expectancy. Despite the advances in the surgical field, 40% of the patients are diagnosed with locally advanced disease which is not suitable for surgery. Radio-frequency ablation (RFA) has been described as a new ‘weapon’ in the multimodal treatment of PDAC, representing a cytoreductive procedure which must be completed with radiotherapy or chemo-radiotherapy. A systematic research was carried out utilizing the PubMed database in regards to this subject, to evaluate the role of RFA in PDAC management. Abstracts, letters-to-the-editor and non-English language manuscripts were excluded. The literature showed that RFA can be used in open and laparoscopic surgery but it is also feasible for endoscopic ultrasound (EUS-guided RFA) or percutaneous approach. Even though we found optimistic and encouraging reports on overall survival (OS), randomized studies are still required to corroborate these findings. Our review research underline that surgical resection remains the only radical treatment option, RFA being a safe and feasible technique reserved for unresectable, non-metastatic pancreatic tumors. Its combination with oncological treatment can improve the OS of these patients.

Radiofrequency ablation and chemotherapy versus chemotherapy alone for locally advanced pancreatic cancer (PELICAN): study protocol for a randomized controlled trial

Background

Approximately 80% of patients with locally advanced pancreatic cancer (LAPC) are treated with chemotherapy, of whom approximately 10% undergo a resection. Cohort studies investigating local tumor ablation with radiofrequency ablation (RFA) have reported a promising overall survival of 26–34 months when given in a multimodal setting. However, randomized controlled trials (RCTs) investigating the effect of RFA in combination with chemotherapy in patients with LAPC are lacking.

Methods

The “Pancreatic Locally Advanced Unresectable Cancer Ablation” (PELICAN) trial is an international multicenter superiority RCT, initiated by the Dutch Pancreatic Cancer Group (DPCG). All patients with LAPC according to DPCG criteria, who start with FOLFIRINOX or (nab-paclitaxel/)gemcitabine, are screened for eligibility. Restaging is performed after completion of four cycles of FOLFIRINOX or two cycles of (nab-paclitaxel/)gemcitabine (i.e., 2 months of treatment), and the results are assessed within a nationwide online expert panel. Eligible patients with RECIST stable disease or objective response, in whom resection is not feasible, are randomized to RFA followed by chemotherapy or chemotherapy alone. In total, 228 patients will be included in 16 centers in The Netherlands and four other European centers. The primary endpoint is overall survival. Secondary endpoints include progression-free survival, RECIST response, CA 19.9 and CEA response, toxicity, quality of life, pain, costs, and immunomodulatory effects of RFA.

Discussion

The PELICAN RCT aims to assess whether the combination of chemotherapy and RFA improves the overall survival when compared to chemotherapy alone, in patients with LAPC with no progression of disease following 2 months of systemic treatment.

Trial registration

Dutch Trial RegistryNL4997. Registered on December 29, 2015. ClinicalTrials.govNCT03690323. Retrospectively registered on October 1, 2018

Role of Radiofrequency Ablation in the Management of Unresectable Pancreatic Cancer

Pancreatic cancer is one of the most aggressive malignancies of the digestive tract and carries a poor prognosis. The majority of patients have advanced disease at the time of diagnosis. Surgical resection offers the only curative treatment, but only a small proportion of patients can undergo surgical resection. Radiofrequency ablation (RFA) is a well-known modality in the management of solid organ tumors, however, its utility in the management of pancreatic cancer is under investigation. Since the past decade, there is increasing use of RFA as it provides a feasible palliation treatment in the management of unresectable pancreatic cancer. RFA causes tumor cytoreduction through multiple mechanisms such as coagulative necrosis, protein denaturation, and activation of anticancer immunity. The safety profile of RFA is controversial because of the high risk for complications, however, small prospective and retrospective studies have shown promising results in its applicability for palliative management of unresectable pancreatic malignancies. In this review, we discuss different approaches of RFA, their indications, technical accessibility, safety, and major complications in the management of unresectable pancreatic cancer.

A computational model to investigate the influence of electrode lengths on the single probe bipolar radiofrequency ablation of the liver

BACKGROUND AND OBJECTIVES

Recently, there have been calls for RFA to be implemented in the bipolar mode for cancer treatment due to the benefits it offers over the monopolar mode. These include the ability to prevent skin burns at the grounding pad and to avoid tumour track seeding. The usage of bipolar RFA in clinical practice remains uncommon however, as not many research studies have been carried out on bipolar RFA. As such, there is still uncertainty in understanding the effects of the different RF probe configurations on the treatment outcome of RFA. This paper demonstrates that the electrode lengths have a strong influence on the mechanics of bipolar RFA. The information obtained here may lead to further optimization of the system for subsequent uses in the hospitals.

METHODS

A 2D model in the axisymmetric coordinates was developed to simulate the electro-thermophysiological responses of the tissue during a single probe bipolar RFA. Two different probe configurations were considered, namely the configuration where the active electrode is longer than the ground and the configuration where the ground electrode is longer than the active. The mathematical model was first verified with an existing experimental study found in the literature.

RESULTS

Results from the simulations showed that heating is confined only to the region around the shorter electrode, regardless of whether the shorter electrode is the active or the ground. Consequently, thermal coagulation also occurs in the region surrounding the shorter electrode. This opened up the possibility for a better customized treatment through the development of RF probes with adjustable electrode lengths.

CONCLUSIONS

The electrode length was found to play a significant role on the outcome of single probe bipolar RFA. In particular, the length of the shorter electrode becomes the limiting factor that influences the mechanics of single probe bipolar RFA. Results from this study can be used to further develop and optimize bipolar RFA as an effective and reliable cancer treatment technique.

Safety of radiofrequency ablation in patients with locally advanced, unresectable pancreatic cancer: A phase II study

INTRODUCTION

Radiofrequency ablation (RFA) has been proposed as a new treatment option for locally advanced, unresectable pancreatic cancer (LAPC). In preparation of a randomized controlled trial (RCT), the aim of this phase II study was to assess the safety of RFA for patients with LAPC.

MATERIALS AND METHODS

Patients diagnosed with LAPC confirmed during surgical exploration between November 2012 and April 2014 were eligible for inclusion. RFA probes were placed under ultrasound guidance with a safety margin of at least 10 mm from the duodenum and 15 mm from the portomesenteric vessels. During RFA, the duodenum was continuously perfused with cold saline to reduce risk for thermal damage. Primary outcome was defined as the amount of major complications (Clavien-Dindo grade ≥III). RFA-related complications were predefined as: pancreatic fistula, pancreatitis, thermal damage to the portomesenteric vessels and duodenal perforation.

RESULTS

In total, 17 patients underwent RFA. Delayed gastric emptying (DGE) requiring endoscopic feeding tube placement occurred in 4 patients (24%) as only major complication. Five patients (29%) had a major complication other than DGE. One (6%) RFA-related major complications occurred. One patient (6%) died due to complications from a biliary leak following hepaticojejunostomy. After evaluation of the first 5 patients, gastrojejunostomy was no longer performed routinely. Since then severe DGE seemed to occur less (3/5 vs. 3/12 grade C DGE).

CONCLUSION

RFA is a major, but safe procedure for patients with LAPC if performed with strict predefined safety criteria. A RCT is currently investigating the true effectiveness of RFA in patients with LAPC.

Computed tomography findings after radiofrequency ablation in locally advanced pancreatic cancer

Purpose

The purpose of the study was to provide a systematic evaluation of the computed tomography(CT) findings after radiofrequency ablation (RFA) in locally advanced pancreatic cancer(LAPC).

Methods

Eighteen patients with intra-operative RFA-treated LAPC were included in a prospective case series. All CT-scans performed prior to RFA and 1 week and 3 months of post-RFA, according to standard regimen, were assessed by two radiologists in consensus, using standardized radiological scoring lists.

Results

51 CT-scans were assessed. One week after RFA, the ablation zone was visible in all patients as a (partially) sharply defined (83%), heterogeneous area (94%). At 3 months of follow-up, the ablation zone was completely invaded by tumor in 67% of patients and still present, but decreased in 33%. In two patients (11%), local thrombosis and/or occlusion of the superior mesenteric vein occurred. The occlusions persisted without clinical consequences and the thrombosis disappeared. A peripancreatic fluid collection was visible 1 week after RFA in 3 patients, wherein the ablation zone extended ventrally outside of the pancreas.

Conclusions

Directly after RFA for LAPC, a well-defined ablation zone is visible on CT-imaging. This ablation zone is usually replaced by tumor ingrowth after 3 months. Moreover, the ablation zone regularly included vascular structures, with rare asymptomatic venous occlusion or thrombosis and without adverse effects on arteries.

Electronic supplementary material

The online version of this article (10.1007/s00261-018-1519-y) contains supplementary material, which is available to authorized users.

Intratumoral radiofrequency hyperthermia-enhanced direct chemotherapy of pancreatic cancer

Purpose

To investigate the technical feasibility of using ultrasound-guided intratumoral radiofrequency hyperthermia (RFH) to enhance local chemotherapy of rat orthotopic pancreatic cancers.

Materials and Methods

Orthotopic pancreatic cancer masses were established by inoculating luciferase/mCherry labeled-pancreatic cancer cells into the pancreatic tails of Lewis model rats via a laparotomy approach. Twenty-four rats with pancreatic cancer and 24 mice with subcutaneous pancreatic cancer xenografts in four study groups (n = 6/group) received various treatments: i) combination therapy of intratumoral MR imaging-heating-guidewire-mediated RFH (42^oC) plus local chemotherapy (gemcitabine); ii) intratumoral chemotherapy alone; iii) RFH alone; and (iv)phosphate-buffered saline (PBS). Transcutaneous ultrasound imaging was used to guide the treatment and subsequently follow changes in tumor sizes. Bioluminescence optical imaging was performed to follow photon signal changes. Sonographic and optical findings were correlated with histology at 14 days.

Results

Optical imaging demonstrated a significantly decreased bioluminescence signal in mice with combination therapy group, compared with the other control groups (0.51±0.18 VS 1.6±0.4 VS 3.18±0.9 VS 3.5±0.96, p < 0.05). Ultrasound imaging showed the smallest tumor volumes of both mice and rat group with the combination therapy, compared with other control groups (0.62±0.16 VS 1.25±0.19 VS 2.28±0.25 VS 2.64±0.26, p < 0.05) and (0.75±0.18 VS 1.31±0.30 VS 1.61±0.28 VS 1.72±0.28, p < 0.05). Both imaging findings were confirmed by histologic correlation.

Conclusion

Intratumoral RFH can augment the chemotherapeutic effect in an orthotopic pancreatic cancer model.

Endoscopic ultrasound-guided radiofrequency ablation in gastroenterology: New horizons in search

Radiofrequency ablation (RFA) has been widely used for the treatment of various solid organ malignancies. Over the last decade, endosonographers have gradually shifted the application of RFA from porcine models to humans to treat a spectrum of diseases. RFA is performed in patients with pancreatic carcinoma who are not candidates for surgery. In this paper, we will discuss various indications for RFA, its procedural details and complications. At present, endoscopic ultrasound-guided RFA is gradually incorporated into the management of various diseases and opens a new avenue for disease treatment.

Multi-modality imaging-monitored creation of rat orthotopic pancreatic head cancer with obstructive jaundice

Purpose

To investigate the feasibility of using multi-modality imaging to monitor the creation of rat models with orthotopic pancreatic head cancer with obstructive jaundice.

Results

27 of 52 rats (51.92%) developed pancreatic head cancer. The tumor formation rate was significantly higher in the animal group receiving bioluminescent tumor, compared to the group receiving non-bioluminescent donor tumors [78.1% (25/32 rats) vs 10.0% (2/20 rats), P = 0.0001]. Both ultrasound imaging and MRI clearly characterized the orthotopic tumors. Laboratory biochemistry test for those rats with obstructive jaundice showed elevated levels of bilirubin, aspartate transaminase (AST), alkaline phosphatase (ALT) and gamma-glutamyl transpeptidase (λ-GGT), compared with those rats without jaundice (P < 0.05). Correlative pathology confirmed that all tumors were ductal adenocarcinomas, and located in pancreatic head regions.

Materials and Methods

Rat pancreatic adenocarcinoma cells (DSL-6A/C1) were first transfected with lentivirus/mCherry-luciferase genes, and then subcutaneously implanted into flanks of donor immunocompetent Lewis rats, to create pancreatic tumor tissues. The tumor tissues from donor rats with either bioluminescence signal or without the signal were then transplanted into the pancreatic heads of 52 recipient Lewis rats. Bioluminescence optical and ultrasound imaging, as well as magnetic resonance imaging (MRI), were performed to follow up the tumor formation and growth in these tumor-transplanted rats. Physical examination and biochemistry test were used to discern the rats with obstructive jaundice. The rats were euthanized for subsequent histologic correlation and confirmation.

Conclusions

We successfully created a new rat model with orthotopic pancreatic head cancer, which can be accurately monitored and visualized by different imaging modalities.

Role of local ablative techniques (Radiofrequency ablation and Irreversible Electroporation) in the treatment of pancreatic cancer

Thanks to continuous research and investment in technology, the ablation of tumors has become common. Through the application of different types of energy is possible to induce cellular injury of the neoplastic tissue, leading to cellular death. Radiofrequency ablation (RFA) and irreversible electroporation (IRE) represent the most applied ablative techniques on pancreatic cancer. RFA and IRE, causing necrosis and apoptosis of neoplastic cells, are able to destroy neoplastic tissue, to drastically modify the neoplastic microenvironment and, possibly, to stimulate both directly and indirectly the anti-tumor immune system. This article provides part of our experience with the application of RFA and IRE on pancreatic adenocarcinoma (PDAC).

Local Ablative Strategies for Ductal Pancreatic Cancer (Radiofrequency Ablation, Irreversible Electroporation): A Review

Pancreatic ductal adenocarcinoma (PDAC) has still a dismal prognosis. Locally advanced pancreatic cancer (LAPC) accounts for the 40% of the new diagnoses. Current treatment options are based on chemo- and radiotherapy regimens. Local ablative techniques seem to be the future therapeutic option for stage-III patients with PDAC. Radiofrequency Ablation (RFA) and Irreversible Electroporation (IRE) are actually the most emerging local ablative techniques used on LAPC. Initial clinical studies on the use of these techniques have already demonstrated encouraging results in terms of safety and feasibility. Unfortunately, few studies on their efficacy are currently available. Even though some reports on the overall survival are encouraging, randomized studies are still required to corroborate these findings. This study provides an up-to-date overview and a thematic summary of the current available evidence on the application of RFA and IRE on PDAC, together with a comparison of the two procedures.

Emerging indications of endoscopic radiofrequency ablation

INTRODUCTION

Radiofrequency ablation (RFA) is a well-validated treatment of dysplastic Barrett's esophagus. Other indications of endoscopic RFA are under evaluation.

RESULTS

Four prospective studies (total 69 patients) have shown that RFA achieved complete remission of early esophageal squamous intra-epithelial neoplasia at a rate of 80%, but with a substantial risk of stricture. In the setting of gastric antral vascular ectasia, two prospective monocenter studies, and a retrospective multicenter study, (total 51 patients), suggest that RFA is efficacious in terms of reducing transfusion dependency. In the setting of chronic hemorrhagic radiation proctopathy, a prospective monocenter study and a retrospective multicenter study (total 56 patients) suggest that RFA is an efficient treatment. A retrospective comparative study (64 patients) suggests that RFA improves stents patency in malignant biliary strictures.

CONCLUSIONS

Endoscopic RFA is an upcoming treatment modality in early esophageal squamous intra-epithelial neoplasia, as well as in gastric, rectal, and biliary diseases.

Radiofrequency Ablation of the Pancreas: Protective Effect of Local Cooling Techniques

Pancreatic carcinoma is one of the commonest malignant diseases today and the majority of patients are suitable for palliative treatment only. Radiofrequency ablation (RFA) has been used extensively for the treatment of solid organ tumors but little is known on the efficacy and safety of pancreatic ablation. To further investigate the safety of pancreatic RFA, 18 pigs had RFA of the pancreas, close to superior mesenteric vein and duodenum. Group A (nine animals) was protected with peripancreatic cool perfusion and Group B (nine animals) with portal vein (PV) intravenous injection of cool saline. Biochemical and histological evidence suggested lateral thermal injury of the duodenal wall and superior mesenteric vein and acute pancreatitis in most animals. However, clinically and at autopsy, Group B animals fared much better. PV thrombosis, hepatic abscess, duodenal perforation, ascites, and extensive pancreatic necrosis were observed in Group A but not in Group B. The present study suggests that PV cool saline perfusion can prevent major complications caused by pancreatic RFA and may be used in combination with other protective techniques in the clinical setting to reduce RFA-associated morbidity.

Radiofrequency ablation of pancreatic ductal adenocarcinoma: The past, the present and the future

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive cancers with a grim overall 5-year survival rate of 5%. Advances in surgical techniques, critical care, molecular diagnosis, diagnostic imaging, endosonology and adjuvant therapy have improved outcomes; but still more needs to be achieved. There is an urgent need to discover new avenues that may impact survival. Radiofrequency ablation (RFA) has attracted attention as an adjunctive treatment in PDAC. A review of English literature in PubMed was done using the MESH terms for PDAC and RFA. All the articles were reviewed and core information was tabulated for reference. After a comprehensive review of all articles the data was evaluated to discover the role of RFA in PDAC management. Indications, contraindications, feasibility, success rate, safety, complications and impact on survival were reviewed and are discussed further. RFA appears to be an attractive option for non-metastatic locally advanced PDAC. RFA is feasible but has a significant morbidity. At the present time the integration of RFA into the management of pancreatic ductal adenocarcinoma is evolving. It should be considered as having a complimentary role to current standard therapy in the multimodal management care model. It is likely that indications and patient selection for pancreatic RFA will expand.

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

OBJECTIVE

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.

METHODS

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.

RESULTS

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 or POPF. The distal pancreas in groups 1 to 3 compared with group 0 and control groups showed a significant increase of small islets (<1000 µm).

CONCLUSIONS

The rapid acinar atrophy of the distal pancreas after RFA and section of the pancreatic ducts in this model does not lead to necrotizing pancreatitis.