Endoscopic ultrasound-guided pancreatic cyst ablation

Long-term outcomes of EUS-guided lauromacrogol ablation for the treatment of pancreatic cystic neoplasms: 5 years of experience

Background and Objectives

We initially reported EUS-guided lauromacrogol ablation (EUS-LA) to treat pancreatic cystic neoplasms (PCNs); however, its long-term effectiveness remains unknown. This study was performed to further determine the effectiveness of EUS-LA in a larger population with a long-term follow-up based on 5 years of experience with EUS-LA.

Materials and Methods

From April 2015 to April 2020, 279 patients suspected of having PCNs were prospectively enrolled, and seventy patients underwent EUS-guided ablation using lauromacrogol alone. Fifty-five patients underwent follow-up, 35 of whom had a follow-up duration of at least 12 months. The effectiveness of ablation was determined based on volume changes.

Results

Among the fifty female and twenty male patients with an overall mean age of 50.3 years, cysts were located in the head/neck of the pancreas in 37 patients (52.9%) and in the body/tail of the pancreas in 33 patients (47.1%). The adverse events rate was 3.6% (3/84), with 14 patients undergoing a second ablation. Among the 55 patients who underwent follow-up, the median cystic volume sharply decreased from 11,494.0 mm³ to 523.6 mm³ (P < 0.001), and the mean diameter decreased from 32.0 mm to 11.0 mm (P < 0.001). Postoperative imaging showed complete resolution (CR) in 26 patients (47.3%) and partial resolution (PR) in 15 (27.3%) patients. CR was observed in 18 (51.4%), and PR was observed in 9 (25.7%) patients among the 35 patients followed for at least 12 months.

Conclusions

EUS-LA was effective and safe for the treatment of PCNs with stable effectiveness based on at least 12 months of follow-up.

Endoscopic ultrasound-guided ablation of pancreatic cystic neoplasms: ready for prime time?

With the increase in the use of cross-sectional diagnostic imaging, there has been a concomitant rise in the rate of detected pancreatic cystic lesions. Recent years have seen the rise of newly developed therapeutic modalities to treat pancreatic lesions via ablation. Specifically, through the use of endoscopic ultrasound-guided therapy, endoscopists can potentially ablate these lesions safely and with minimally invasive techniques. In this manuscript we review 4 major endoscopic ultrasound-guided ablative therapies: radiofrequency ablation, ethanol injection, chemo ablation, and cryoablation. We also review the efficacy and safety of these techniques and future directions in the management of cystic pancreatic lesions.

Clinical Approach to Incidental Pancreatic Cystic Neoplasm in Outpatient Clinics

Cystic lesions of the pancreas are increasingly observed due to increased use of abdominal images. The malignant rate of pancreas cystic lesion varies widely between various types. Identification of malignant or high-risk lesions is important when determining the appropriate course of management. Using these image findings, including cyst size, presence of solid components, and pancreatic duct involvement, the 2012 International Association of Pancreatology (IAP) and the 2015 American Gastroenterological Association (AGA) guidelines provide a rationale in identifying higher risk patients requiring further workups using an endoscopic ultrasound (EUS). EUS with fine needle aspiration and cytology allows confirmation of the cyst type and determines the risk of malignancy. Small cysts with no suspicious features may undergo the regular imaging study for regular surveillance due to low risk for malignancy. In this review, the differences between the 2012 IAP and 2015 AGA guidelines are presented, In addition to possible recommendations for management and surveillance.

Endoscopy-guided ablation of pancreatic lesions: Technical possibilities and clinical outlook

Endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP)-guided ablation procedures are emerging as a minimally invasive therapeutic alternative to radiological and surgical treatments for locally advanced pancreatic cancer (LAPC), pancreatic neuroendocrine tumours (PNETs), and pancreatic cystic lesions (PCLs). The advantages of treatment under endoscopic control are the real-time imaging guidance and the possibility to reach a deep target like the pancreas. Currently, radiofrequency probes specifically designed for ERCP or EUS ablation are available as well as hybrid cryotherm probe combining radiofrequency with cryotechnology. To date, many reports and case series have confirmed the safety and feasibility of that kind of ablation technique in the pancreatic setting. Moreover, EUS-guided fine-needle injection is emerging as a method to deliver ablative and anti-tumoral agents inside the tumuor. Ethanol injection has been proposed mostly for the treatment of PCLs and for symptomatic functioning PNETs, and the use of gemcitabine and paclitaxel is also interesting in this setting. EUS-guided injection of chemical or biological agents including mixed lymphocyte culture, oncolytic viruses, and immature dendritic cells has been investigated for the treatment of LAPC. Data on the long-term efficacy of these approaches, and large prospective randomized studies are needed to confirm the real clinical benefits of these techniques for the management of pancreatic lesions.

Pancreatic Solid and Cystic Neoplasms: Diagnostic Evaluation and Intervention

High-resolution imaging modalities, such as multi-detector computed tomography, MR imaging, and endoscopic ultrasound, are frequently used alone or in combination to characterize focal solid and cystic pancreatic neoplasms. Imaging in solid pancreatic neoplasms, typically adenocarcinoma and neuroendocrine tumors, is primarily used to detect and stage the extent of the tumor and to determine if complete surgical resection for cure is feasible. In cystic pancreatic masses, imaging aims to differentiate benign nonmucinous cystic lesions from potentially or frankly malignant mucin-producing cysts. Several noninvasive and invasive treatment options can be performed if surgical resection is not possible or contraindicated.

Endoscopic diagnosis and treatment of pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (PNETs) are rare pancreatic neoplasms comprising only 1% to 2% of all pancreatic tumors. In recent years, the number of incidentally discovered PNETs has greatly increased given the widespread use of axial imaging. However, a significant proportion of PNETs may not be visualized on conventional imaging such as computed tomography, magnetic resonance imaging, and somatostatin receptor scintigraphy. Endoscopic ultrasound (EUS) has become an integral part of the diagnosis of PNETs because of its high sensitivity for detecting, localizing, and diagnosing PNETs. EUS-guided tissue acquisition provides histologic and immunologic confirmation, and may also allow prognostication about tumor behavior. In addition to preoperative assessment of these tumors, EUS has also been shown to have an important role in nonoperative management of small nonfunctional PNETs. Finally, recent developments suggest that interventional EUS may be used to aid intraoperative localization of PNETs and to deliver therapeutic agents for the treatment of PNETs. This review will discuss the endoscopic diagnosis and treatment of PNETs, with focus on recent advances in the utility of EUS in the clinical management of these tumors.

The role of therapeutic endoscopic ultrasound now and for the future

Therapeutic endoscopic ultrasound (EUS) became possible after the advent of the linear echoendoscope and the EUS guided fine needle aspiration. Over the past two decades, the indications for therapeutic EUS have expanded and evidence regarding its utility has been steadily accumulating. Randomized studies have shown EUS to be effective for cancer pain relief (celiac plexus neurolysis), pancreatic fluid collection drainage, and biliary drainage. Prospective studies have shown EUS-guided biliary drainage to be safe and effective in patients with failed ERCP. There is evidence to suggest that EUS is effective for pancreatic duct drainage, gallbladder drainage, and drainage of pelvic collections. EUS may also be useful for targeted cancer treatment via brachytherapy, radiofrequency ablation, or injection therapy. Therapeutic EUS is likely to play an increasingly important role in endoscopic therapy of gastrointestinal diseases in the near future.

Interdisciplinary management of cystic neoplasms of the pancreas

Cystic neoplasms of the pancreas are increasingly recognized due to the frequent use of abdominal imaging. It is reported that up to 20% of abdominal cross-sectional scans identify incidental asymptomatic pancreatic cysts. Proper characterization of pancreatic cystic neoplasms is important not only to recognize premalignant lesions that will require surgical resection, but also to allow nonoperative management of many cystic lesions that will not require resection with its inherent morbidity. Though reliable biomarkers are lacking, a wide spectrum of diagnostic modalities are available to evaluate pancreatic cystic neoplasms, including radiologic, endoscopic, laboratory, and pathologic analysis. An interdisciplinary approach to management of these lesions which incorporates recent, specialty-specific advances in the medical literature is herein suggested.