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

Radiofrequency ablation (RFA) in unresectable pancreatic adenocarcinoma: meta-analysis & systematic review

BACKGROUND

Pancreatic adenocarcinoma remains a challenging malignancy with a poor prognosis. Radiofrequency ablation (RFA) has emerged as a potential treatment for unresectable pancreatic adenocarcinoma (UPAC) aimed at improving survival and quality of life. This meta-analysis and systematic review evaluates the outcomes of RFA in UPAC.

METHODS

A comprehensive search was conducted in MEDLINE, Embase, Scopus, and Cochrane Central databases from inception to October 2023. Studies included patients over 18 years with UAPC undergoing RFA. Survival rates and complication rates were assessed as primary outcomes. Data were pooled using random-effects models, and heterogeneity was assessed with I2 statistics. ROBINS-I tool was used for quality assessment.

RESULTS

Nine studies encompassing 265 patients met the inclusion criteria. The mean age was 64.5 years, with 42.5% female participants. Survival analysis showed that at 30 days post-RFA, the mortality rate was 3.3%. At 6 months, the mortality rate was 20.9%, increasing to 50.4% at 12 months. At 24 months, the mortality rate was 61.9%. The pooled mean survival period at 12 and 24 months was 9.18 months and 14.26 months, respectively. Overall, 78.4% of patients died during the follow-up period, with an overall mean survival period of 12.27 months. The most common were intra-abdominal (10.1%), pancreatic (9.8%), and hepatobiliary (6.7%) complications.

CONCLUSIONS

RFA shows potential in the management of unresectable pancreatic adenocarcinoma, with a manageable safety profile. However, the high heterogeneity and risk of bias in available studies highlight the need for well-designed randomized controlled trials to confirm these findings and establish standardized protocols.

State-of-the-Art and Upcoming Innovations in Pancreatic Cancer Care: A Step Forward to Precision Medicine

Pancreatic cancer remains a social and medical burden despite the tremendous advances that medicine has made in the last two decades. The incidence of pancreatic cancer is increasing, and it continues to be associated with high mortality and morbidity rates. The difficulty of early diagnosis (the lack of specific symptoms and biomarkers at early stages), the aggressiveness of the disease, and its resistance to systemic therapies are the main factors for the poor prognosis of pancreatic cancer. The only curative treatment for pancreatic cancer is surgery, but the vast majority of patients with pancreatic cancer have advanced disease at the time of diagnosis. Pancreatic surgery is among the most challenging surgical procedures, but recent improvements in surgical techniques, careful patient selection, and the availability of minimally invasive techniques (e.g., robotic surgery) have dramatically reduced the morbidity and mortality associated with pancreatic surgery. Patients who are not candidates for surgery may benefit from locoregional and systemic therapy. In some cases (e.g., patients for whom marginal resection is feasible), systemic therapy may be considered a bridge to surgery to allow downstaging of the cancer; in other cases (e.g., metastatic disease), systemic therapy is considered the standard approach with the goal of prolonging patient survival. The complexity of patients with pancreatic cancer requires a personalized and multidisciplinary approach to choose the best treatment for each clinical situation. The aim of this article is to provide a literature review of the available treatments for the different stages of pancreatic cancer.

Preclinical Study of Biphasic Asymmetric Pulsed Field Ablation

Pulsed field ablation (PFA) is a novel method of pulmonary venous isolation in atrial fibrillation ablation and is featured by tissue-selective ablation. Isolation is achieved via the application of high-voltage microsecond pulses that create irreversible perforations in cell membranes (i.e., electroporation). We proposed a new biphasic asymmetric pulse mode and verified the lesion persistence and safety of this mode for pulmonary vein ostia ablation in preclinical studies. We found that biphasic asymmetric pulses can effectively reduce muscle contractions and drop ablation threshold. In the electroanatomic mapping, the ablation site showed a continuous low potential area, and the atrium was not captured after 30 days of pacing. Pathological staining showed that cardiomyocytes in the ablation area were replaced by fibroblasts and there was no damage outside the ablation zone. Our results show that pulmonary venous isolation using the biphasic asymmetric discharge mode is safe, durable, effective, and causes no damage to other tissues.

Study on Optimal Parameter and Target for Pulsed-Field Ablation of Atrial Fibrillation

Pulsed-field ablation (PFA) had potential advantages in atrial fibrillation ablation, and we aim to confirm the optimal parameter and target of PFA for atrial fibrillation. Two ablation modes in vitro of single-cell system (ablation in electrode cup) and monolayer cell system (ablation in inserts with electrode tips) were established to perform PFA for myocardial cell H9C2 and smooth muscle cell A7r5. Ablation effect, calcium ion influx, the expression of Cx45, and surface morphological change were observed. Three Bama minipigs were used to verify the in vivo ablation effect of PFA. In monolayer cell system, H9C2 was significantly sensitive to PFA compared with A7r5, with shrinking of the whole monolayer. The ablation effect of bidirectional pulse was weaker than that of the two mono-polar pulses. Expressed Cx45 proteins were increased in H9C2 but decreased in A7r5 cells. Bidirectional PFA performed on Bama minipigs was able to effectively block electrical activity from the pulmonary vein to the atrium with week muscle contraction, not generating pulmonary vein stenosis. Bidirectional PFA was able to significantly ablate myocardial cells, maintain cell–cell connection, and reduce muscle contraction, which was a kind of optimized PFA strategy for atrial fibrillation.

Pancreatoduodenectomy associated with colonic resections: indications, pitfalls, and outcomes

Pancreatoduodenectomy (PD) associated with colonic resections (CR) (PD-CR) might be a viable option in case of locally advanced periampullary tumors or right colon cancer. The aim of this review was to reappraise the indications and outcomes of PD-CR focusing on the occurrence of postoperative pancreatic fistula (POPF) and colonic anastomotic leak (CAL). A systematic literature search was performed in Medline and Cochrane Central Register of Controlled Trials (CENTRAL) for studies published between 2000 and 2020 concerning PD-CR for periampullary or colonic neoplasms. Twenty-seven studies were selected. Morbidity after PD-CR ranged from 12 to 65% and surgery-related mortality was approximately 10%. When reported, the rates of POPF and AL were as high as 40% and 33%, respectively. The oncological results were strictly linked to the nature of the primary tumor and did not significantly differ from those achieved with standard resections. Surgical radicality and nodal status resulted the main determinants of outcome for pancreatic and colonic cancer, respectively. Solid evidence about the surgical outcomes of PD-CR is lacking, mainly due to the small proportion of patients undergoing such combined resection. Given the elevated surgical risk, a multidisciplinary evaluation is recommended for patient's selection. The increasing use of neoadjuvant therapies is expected to further change the indications and outcomes of PD-CR in the next future.

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.

Clinical effectiveness of combined interventional therapy as a salvage modality for unresectable pancreatic carcinoma

Although different treatment methods have been introduced to treat advanced pancreatic carcinoma, the median overall survival rate remains unsatisfactory. Theoretically, combining different treatment methods should work in synergy to enhance locoregional disease control and improve survival. Therefore, the aim of the present retrospective study was to analyze the effectiveness of combined interventional therapy compared with trans-arterial chemoembolization (TACE) or chemotherapy alone for the treatment of unresectable pancreatic carcinoma. A total of 266 patients who were undergoing treatment for unresectable pancreatic carcinoma between July 2012 and November 2015 were included in the current study. The tumor responses and 3-year overall survival rates of patients treated with combined interventional therapy (TACE combined with iodine-125 seed implantation and/or radiofrequency ablation; CIT group; n=84) were compared with those of patients treated with TACE alone (TACE group; n=59), as well as patients treated with systemic chemotherapy alone (control group; n=123). Patients in the CIT group exhibited significantly improved tumor responses compared with patients in the TACE group (51.89 vs. 30.61%; P=0.028) or control group (51.89 vs. 17.20%; P<0.001). The 3-year overall survival rate of the CIT group was also significantly higher compared with that of the TACE and control groups (P=0.0116 and P=0.0001, respectively). Furthermore, the CIT group exhibited a significantly higher overall survival rate for patients with unresectable metastatic pancreatic cancer compared with the TACE and control groups (P=0.0088 and P<0.0001, respectively), which suggests that a combination of different interventional techniques increases the survival of patients with unresectable pancreatic cancer. No life-threatening complications were observed in any treatment group. In conclusion, combined interventional therapy exhibits a good efficacy and an improved survival rate for unresectable pancreatic cancer compared with TACE alone.

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.

Ultrasound-guided percutaneous procedures in pancreatic diseases: new techniques and applications

Ultrasound (US) is not only an important diagnostic tool for the evaluation of the pancreas, but is also a fundamental imaging technique to guide percutaneous interventions for several pancreatic diseases (fluid aspiration and drainage; invasive diagnosis by means fine-needle aspiration and core-needle biopsy; tumour ablation by radiofrequency, microwaves, irreversible electroporation, cryoablation, and high-intensity focused US). Technical improvements, such as contrast media and fusion imaging, have recently increased precision and safety and reduced procedure-related complications. New treatment US techniques for the ablation of pancreatic tumours, such as contrast-enhanced US and multimodality fusion imaging, have been recently developed and have elicited a growing interest worldwide. The purpose of this article was to review the most up-to-date role of US in percutaneous procedures for pancreatic diseases.