Endoscopic ultrasound-guided radiofrequency ablation of pancreatic insulinoma: a state of the art review

Endoscopic ultrasound guided liver biopsy and portal pressure gradient: when, why and how? Can it become the standard of care in endo-hepatology?

INTRODUCTION

The armamentarium of 'Endo-hepatology' is proliferating with the advancements in techniques and availability of new devices in the field of endoscopic ultrasound (EUS). This has resulted in the merger of multitude of diagnostic and therapeutic interventions, such as EUS-liver biopsy (LB), EUS-angioembolization of gastric varices, EUS-portal pressure gradient (PPG) measurement, and others into a 'one-stop-shop' for efficient patient management. Lack of standardization of these techniques forms a major hinderance in their widespread adoption.

AREAS COVERED

A comprehensive literature search was undertaken across various databases on EUS-LB and EUS-PPG till November 2024 for reviews, observational studies, and randomized trials on EUS-LB and EUS-PPG, describing its indications, technique, and data of safety and efficacy, detailing its role in day-to-day clinical practice.

EXPERT OPINION

EUS-LB and EUS-PPG have shown promise in the ever-growing field of endo-hepatology. EUS-LB has exhibited excellent safety profile and comparable tissue yield compared to its percutaneous counterpart. On the other hand, EUS-PPG seems to be a viable alternative although it needs to be standardized further. From a patient and hospital perspective, they might prove to be convenient and cost-effective. Nevertheless, more evidence is warranted before they can be labeled as the new standard of care.

Reducing the incidence of pancreatic cancer through radiofrequency ablation of mucinous cystic neoplasms: What is the evidence?

Pancreatic cystic lesions are mostly discovered incidentally during cross-sectional imaging for other indications. They range from benign cysts to premalignant lesions, posing a risk for development of pancreatic cancer. Surveillance of cysts with low-risk features and surgical resection of high-risk ones has been the standard of care. However, the lack of consensus between national society guidelines results in discordant management and follow-up. One of the upcoming therapeutic modalities for pancreatic cysts, including mucinous cystic neoplasms (MCN), is endoscopic ultrasound (EUS)-guided interventions, including injection of chemotherapeutic agents or EUS-guided radiofrequency ablation (EUS-RFA). EUS-RFA is emerging as a promising minimally invasive tool with the need for further investigation to understand its clinical utility. This review discusses the physiology, clinical studies, adverse events, and future perspectives of RFA for various pancreatic lesions, with particular regard with MCN.

Pancreatic Neuroendocrine Neoplasms: Classification and Novel Role of Endoscopic Ultrasound in Diagnosis and Treatment Personalization

The incidence and prevalence of pancreatic neuroendocrine neoplasms are steadily increasing. These tumors are highly heterogeneous, with treatment options ranging from observation to surgery, and various medical therapies. The choice of treatment is influenced by factors such as tumor stage, grade (proliferative activity), and the presence of hormone-related syndromes. Endoscopic ultrasound (EUS) is becoming increasingly valuable for assessing pancreatic neuroendocrine neoplasms, offering detailed morphological, vascular, and functional information through techniques such as contrast enhancement and elastography. It also allows biopsies that are useful for both histopathological and molecular analyses. These tumors are highly heterogeneous, with treatment options ranging from observation to various medical therapies and surgery. Recent data suggest that small, non-functioning PanNENs with low proliferation rates may be safely monitored, whereas more aggressive or functioning tumors typically require surgery. EUS-guided ablation is a promising alternative for patients with functional pancreatic neuroendocrine neoplasms who are unsuitable for surgery, although randomized trials are needed. In non-resectable pancreatic neuroendocrine neoplasms, treatment options include somatostatin analogs, targeted therapies (e.g., everolimus, sunitinib), chemotherapy, and radioligand therapy. This review discusses key factors in planning personalized treatment strategies for pancreatic neuroendocrine neoplasms.

Diagnosis and management of benign secreting pancreatic insulinoma: What's new? 4 case report

Introduction and importance: Even though insulinoma is the most frequent neuroendocrine tumor, it represents only 2% of pancreatic 2% of all pancreatic neoplasms. Diagnosis is relatively simple, and surgery after accurate determination of the tumors location within the pancreas is the cornerstone of its treatment. Case presentation: We herein report 4 patients undergoing various surgeries for benign secreting insulinomas, after extensive radiological and endoscopic exploration. Clinical discussion: Diagnosis is relatively simple relying on clinical and biological criteria, it must be followed by an extensive and accurate preoperative determination of the tumors localization. The laparoscopic tumoral enucleation is the treatment of choice for small isolated tumors, but open surgery still has its indications. Conclusion: Pancreatic insulinoma is a rare neuroendocrine tumor that can be life-threatening due to hypoglycemic manifestations. The diagnosis is based on clinical and biological criteria. echo endoscopy and to a lesser extent radiological exploration can precisely determine the tumors location. Laparoscopic surgical enucleation of the tumor remains the preferred curative treatment.

Percutaneous Ultrasound-Guided Radiofrequency Ablation as a Therapeutic Approach for the Management of Insulinomas and Associated Metastases in Dogs

Insulinomas are the most common neoplasms of the endocrine pancreas in dogs, leading to persistent hypoglycemia due to inappropriate insulin secretion. The standard treatment is surgical resection, but it carries significant risks, including pancreatitis and diabetes mellitus. This study investigates the efficacy and safety of percutaneous ultrasound-guided radiofrequency ablation (RFA) as an alternative to surgery. A total of 29 dogs diagnosed with insulinoma were treated with RFA, targeting both primary pancreatic tumors and metastases in regional lymph nodes or the liver. Blood glucose levels and tumor size were monitored before and after the procedure. RFA led to a significant increase in blood glucose levels and a reduction in tumor size in all patients, with minimal postoperative complications. The results suggest that RFA is a feasible and effective treatment option for insulinomas in dogs.

Role of Endoscopic Ultrasound-Guided Radiofrequency Ablation in Pancreatic Lesions: Where Are We Now and What Does the Future Hold?

Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has emerged as an effective and minimally invasive treatment for pancreatic lesions, particularly in patients at high surgical risk. Utilizing thermal energy, RFA induces the coagulative necrosis of the tissue and potentially triggers immunomodulation by releasing intracellular antigens. Numerous studies have confirmed the technical feasibility, safety, and efficacy of EUS-RFA in pancreatic neuroendocrine tumors and premalignant cystic lesions, with an acceptable profile of adverse events. The technique's potential immunomodulatory effects offer intriguing implications for the treatment of advanced pancreatic malignancies, encouraging further evaluation. This review paper aims to highlight the EUS-RFA principles, technology, and clinical applications in various pancreatic lesions and safety, and the future research directions.

Harnessing endoscopic ultrasound-guided radiofrequency ablation to reshape the pancreatic ductal adenocarcinoma microenvironment and elicit systemic immunomodulation

Pancreatic ductal adenocarcinoma (PDAC) is characterized by poor prognostics and substantial therapeutic challenges, with dismal survival rates. Tumor resistance in PDAC is primarily attributed to its fibrotic, hypoxic, and immune-suppressive tumor microenvironment (TME). Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA), an Food and Drug Administration (FDA)-approved minimally invasive technique for treating pancreatic cancer, disrupts tumors with heat and induces coagulative necrosis, releasing tumor antigens that may trigger a systemic immune response-the abscopal effect. We aim to elucidate the roles of EUS-RFA-mediated thermal and mechanical stress in enhancing anti-tumor immunity in PDAC. A comprehensive literature review focused on radiofrequency immunomodulation and immunotherapy in pancreatic tumors to understand the pathophysiological mechanisms of RFA and its effect on the TME, which could prevent recurrence and resistance. We reviewed clinical, preclinical, and in vitro studies on RFA mechanisms in pancreatic adenocarcinoma, discussing the unique immunomodulatory effects of EUS-RFA. Recent findings suggest that combining RFA with immune adjuvants enhances responses in pancreatic adenocarcinoma. EUS-RFA offers a dual benefit against PDAC by directly reducing tumor viability and indirectly enhancing anti-tumor immunity. Observations of neutrophil-mediated immunomodulation and programmed cell death ligand 1 (PD-L1) modulation support integrating EUS-RFA with targeted immunotherapies for managing pancreatic adenocarcinoma. Integrating EUS-RFA in PDAC treatment promises direct cytoreduction and synergistic effects with molecular targeted therapies. Prospective clinical trials are crucial to assess the efficacy of this combined approach in improving outcomes and survival rates in advanced PDAC cases.

Endoscopic ultrasound-guided pancreatic duct drainage: a comprehensive state of the art review

INTRODUCTION

Endoscopic retrograde pancreatography (ERP) has traditionally been the standard modality for pancreatic endotherapy. However, in certain situations, failure of retrograde ductal access may warrant an alternative modality of drainage. This can occur in various settings like difficult and/or surgically altered anatomy or duodenal obstruction. Endoscopic ultrasound-guided pancreatic duct drainage (EUS-PDD) is a relatively newer addition to the armamentarium for endoscopic access to the PD.

AREAS COVERED

This comprehensive state-of-art review aims to give an overview of the indications, technical details, different approaches, and outcomes of EUS-PDD, with the latest evidence available in scientific literature.

EXPERT OPINION

Akin to its biliary drainage counterpart, EUS-PDD enables an EUS-assisted-ERP using rendezvous technique or EUS-guided drainage through transmural stenting. The technique has evolved over the ensuing years with multitude of accessories, approaches, and devices to optimize the outcomes. However, the technical success and adverse events rates need to be further improved. Additionally, it has a steep learning curve with requirements of advanced technical skill and optimum infrastructure back-up. Meticulous patient selection, precise knowledge of ductal anatomy, appropriate approach, and carefully chosen accessories can improve its clinical outcomes.