EUS-guided Radiofrequency Ablation Research Articles

EUS-Guided Radiofrequency Ablation Therapy for Pancreatic Neoplasia.

Radiofrequency ablation (RFA) under endoscopic ultrasound (EUS) guidance has been developed and utilized over the last decade to provide the loco-regional treatment of solid and cystic pancreatic neoplastic lesions. The advantage of this approach relies on the close proximity of the EUS transducer to the target pancreatic lesion, which, coupled with the development of specifically designed RFA ablation devices, has made the procedure minimally invasive, with a clear reduction in adverse events as compared to the high morbidity of the surgical approach. EUS-RFA has been applied so far to pancreatic functional and non-functional neuroendocrine neoplasms, pancreatic ductal adenocarcinoma or metastases to the pancreas, and pancreatic neoplastic cysts. Excluding neuroendocrine tumors, for other indications, most of these procedures have been performed in patients who refused surgery or were at high surgical risk. More studies evaluating EUS-RFA in selected patients, not at surgical risk, are gradually becoming available and will pave the road to extend the indications for this therapeutic approach, also in association with other oncological therapies. The present manuscript will critically review the available evidence in the field of the EUS-guided RFA of solid and cystic pancreatic neoplasms.

EUS-guided radiofrequency ablation for pancreatic adenocarcinoma

Emerging data suggest neoadjuvant chemotherapy (NAC) for resectable pancreatic ductal adenocarcinoma (PDAC) is associated with improved survival. However, less than 40% of patients demonstrate a meaningful radiographic response to NAC. EUS-guided radiofrequency ablation (EUS-RFA) has emerged as a new modality to treat PDAC. We hypothesize that NAC plus EUS-RFA can be used in the management of resectable PDAC. This was a prospective review of PDAC patients meeting the criteria of resectable tumor anatomy who underwent NAC chemotherapy plus EUS-RFA followed by pancreatic resection. Radiographic imaging and perioperative and short-term outcomes were recorded. Surgical pathology specimens were analyzed for treatment response. Three eligible patients with resectable PDAC received 4 months of NAC plus EUS-RFA. One month after completing NAC and EUS-RFA, all 3 patients underwent standard pancreaticoduodenectomy without adverse events. After a 6-week recovery, all patients completed 2 months of postoperative adjuvant chemotherapy. In our institutional experience, this treatment protocol appears to be safe as patients tolerated the combination of chemotherapy and ablation. Patients underwent pancreatic resection with uneventful recovery. This novel neoadjuvant approach may provide a more effective alternative to chemotherapy alone.

Endoscopic loco-regional treatment in controlling pancreatic neuroendocrine tumors (PNETs) behavior: a case series and literature review.

Pancreatic neuroendocrine tumors (PNETs) are considered rare pancreatic neoplasms, and it is a challenging disease entity due to its indolent behavior and is difficult to manage. Diagnostic challenge is usually found in the imaging-based approach, such as transabdominal ultrasound, abdominal CT scan, and abdominal MRI. Surgery is still the main key player in controlling the disease. The main problems in clinical practice are the early detection of small PNETs lesion and non-functional PNET (NF-PNET) cases. Most cases usually come with large tumor size or metastatic disease. Endoscopic ultrasound (EUS) has been well-known as the most sensitive tool for early detection of pancreatic malignancy. It has now also been developed for managing pancreatic cancer, such as tumor ablation therapy. We presented four variety of PNETs cases (one patient with non-functioning PNETs and three patients with functioning PNETs) who have been successfully treated with EUS-guided radiofrequency ablation (RFA) with good control of tumor growth during follow-up. One patient with a large-size insulinoma could have the tumor controlled gradually after several EUS-RFA sessions. No adverse events or major complications were observed during and after the EUS-RFA procedure. EUS has been shown as a promising tool not only for more accurate diagnosis but also for tumor growth control. However, it would need further comparison studies between EUS and surgical approaches to make a better treatment strategy.

Assessing EUS-guided radiofrequency ablation in unresectable pancreatic ductal adenocarcinoma: a single-center historic cohort study

/aims: Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has emerged as an alternative for the local treatment of unresectable pancreatic ductal adenocarcinoma (PDAC). We aim to assess the feasibility and safety of EUS-RFA in patients with unresectable PDAC. The following was a historic cohort compounded by locally advanced (LA) and metastatic (m) PDAC naïve patients, who underwent EUS-RFA between October 2019 to March 2022. EUS-RFA was performed with a 19-g needle electrode with a 10 mm active tip for energy delivery. Study primary endpoints were feasibility, safety, and clinical follow-up; secondary endpoints were performance status (PS), local control (LC) and overall survival (OS). Twenty-six patients were selected: 15/26 LA-PDAC and 11/26 mPDAC. Technical success was achieved in all patients with no major adverse events. Six months after EUS-RFA, OS was 11/26 (42.3%), with significant PS improvement (P=.03). LC was achieved, with tumor reduction from 39.5 to 26 mm (P=.04). Post-treatment hypodense necrotic area was observed at six-month follow-up in 11/11 alive cases. Metastatic disease was a significant factor for OS worsening (HR 5.021; IC 95% 1.589 - 15.87; P=.004) CONCLUSIONS: EUS-RFA of pancreatic adenocarcinoma is a minimally invasive and safe technique that may have an important role as targeted therapy for local treatment of unresectable cases, as well as an alternative for poor surgical candidates. Also, RFA may play a role in downstaging cancer with potential OS increase in non-metastatic cases. Large prospective cohorts are required to evaluate this technique in clinical practice.

Endoscopic radiofrequency ablation of pancreatic neuroendocrine tumors

Aim. To present the first experience of EUS-guided radiofrequency ablation in the treatment of patients with functioning neuroendocrine tumors of the pancreas. Materials and methods. Endoscopic radiofrequency ablation was performed in 2 patients with insulin-producing neuroendocrine tumor of the pancreatic head and clinical picture of organic hyperinsulinism. The radiofrequency ablation system includes a 19-gauge needle electrode to be conducted through the forceps aperture, a generator and an intraelectrode cooling system. Results. The efficacy of ultrasound-guided radiofrequency ablation in the cases presented above appears to be clinically proven. The outcomes include stabilization of the blood glucose level, a complete elimination of hypoglycemia-associated clinical symptoms. Both observations reveal no complications after the procedure. Conclusion. EUS-guided radiofrequency ablation appears to possess a potential for wider application as a minimally invasive intervention, thus introducing an alternative to surgical treatment of patients with neuroendocrine tumors of the pancreas. An experience of EUS-guided radiofrequency ablation is worth to be accumulated and outcomes of the method application to be analyzed on a larger number of clinical observations.

Comparative efficacies and safeties of cylindrical interstitial laser ablation and radiofrequency ablation on swine pancreas.

Laser ablation (LA) has been evaluated for the minimally invasive thermal treatment of various cancers, but conventional unidirectional endoscopic ultrasound (EUS)-guided LA has limitations. Therefore, we developed a cylindrical laser diffuser to overcome the limitations of unidirectional EUS-guided LA. The purpose of this study was to compare the efficacies and safeties of EUS-guided LA using a novel cylindrical laser diffuser and radiofrequency ablation (RFA) in vivo in swine pancreas. EUS-guided RFA (15 W, 30s, 450J) and cylindrical interstitial LA (CILA) (5 W, 90s, 450J) were applied to normal pancreatic tissue in six anesthetized pigs (three per group). Laboratory tests were performed at baseline, immediately after ablation (day 0), and 2days after procedures (day 2). Two days after procedures, all pigs were sacrificed, and histopathological safety and efficacy assessments were performed. Technically, EUS-guided RFA and CILA were performed successfully in all cases. No major complications, including perforation or acute pancreatitis, occurred during the experiment in either group. All animals remained in excellent condition throughout the experimental period, and laboratory tests provided no evidence of a major complication. Average necrotic volumes in the RFA and CILA groups were 424.2 mm3 and 3747.4 mm3, respectively, and average necrotic volume was significantly larger in CILA group (p < 0.001). EUS-guided RFA and CILA had acceptable safety profiles in the normal swine pancreas model. Our findings indicate EUS-guided CILA has potential for the effective local treatment of pancreatic cancer as an alternative to EUS-guided RFA.

EUS-guided radiofrequency ablation of solid pancreatic lesions: An updated review.

Recent years have brought to light newly developed therapeutic modalities for the treatment of premalignant and malignant pancreatic lesions. The role of EUS-guided radiofrequency ablation (EUS-RFA) as a treatment modality for malignant pancreatic lesions is still under evaluation. Several animal studies and human studies have demonstrated the safety and efficacy of EUS-RFA in the management of premalignant and malignant pancreatic lesions. EUS-RFA therapy can potentially ablate these lesions safely and with minimally invasive techniques. In this article, we provide an updated review of the application of EUS-RFA of pancreatic lesions. We also review the clinical efficacy and safety of this technique and future directions.

Endoscopic radiofrequency ablation under the control of ultrasonography as a new method of treatment of neuroendocrine pancreatic tumors and analgesia option for locally advanced forms of pancreatic cancer. First experience in Russia

Background. Radiofrequency ablation (RFA) of pancreatic NET up to 20 mm in size under endosonographic control (EUS) may become the method of choice in the treatment of this group of patients, as well as an option for analgesia in patients with locally advanced forms of pancreatic cancer. Aim. Describe the RFA – EUS technique, evaluate the safety and efficacy of the RFA – EUS method in the treatment of NET of the pancreas, up to 2.0 cm in diameter, and ablation of the celiac plexus in a cohort of patients with locally advanced forms of pancreatic cancer in order to relieve pain. Materials and Methods. In a prospective ongoing observational study conducted at the FSBI “N. N. Blokhin national Medical Research Center of Oncology” of the Ministry of Health of Russia from September 2022 to June 2023, data of 10 patients with resectable NET and unresectable malignant neoplasms of the pancreas were analyzed. The main method of treatment in 100 % of cases was RFA – EUS, performed for the first time in Russia. All patients at the first stage underwent esophagogastroduodenoscopy (EGDS) and endosonographic study with fine needle aspiration biopsy (EUS-TAB) to verify the diagnosis. At the second stage, all patients underwent RFA – EUS. The main evaluated parameter in the group of patients with NET was the absence of residual tumor tissue after RFA – EUS, according to Endo-US and MRI, the nature of changes in the pancreatic tissue after RFA was additionally assessed – fibrous or necrotic changes in the area of RFA – EUS. The main parameter evaluated in the group of patients with unresectable pancreatic cancer was the absence of pain within 8 weeks. and complete withdrawal from opioid analgesics 3–5 days after RFA – EUS. Results. According to the results of a morphological study, the diagnosis of pancreatic NET was confirmed in 7 (70 %) patients, adenocarcinoma – in 3 (30 %). Technical success, defined as a complete endosonographic and radiological response 3 months after the intervention in the group of patients with pancreatic NET (n = 7; 70 %) and complete withdrawal of opioid analgesics at 3–5 days, with the preservation of the analgesic effect for 8 weeks. after RFA – EUS, was achieved in 100 % of cases (n = 3; 30 %). Return to opioid analgesics after 3 months RFA – EUS in the group of patients with adenocarcinoma of the pancreas (n = 3; 30 %) was noted in 20 % of cases (n = 2), which required re-intervention, in 10 % (n = 1) – it was not possible to estimate the duration of the analgesic effect due to the death of the patient 2 months after RFA – EUS, the median follow-up was 6 months. Conclusion. The results of the study are the first experience of using RFA – EUS in the treatment of malignant neoplasms of the pancreas. EUS-guided RFA is an effective, minimally invasive and safe treatment for pancreatic NET, up to 2.0 cm in diameter, as well as an analgesic option for advanced pancreatic cancer. To determine the indications, contraindications and effectiveness of RFA in the radical and symptomatic treatment of malignant neoplasms of the pancreas, it is necessary to conduct large prospective multicenter studies.

EUS-guided radiofrequency ablation plus chemotherapy versus chemotherapy alone for pancreatic cancer (ERAP): An observational open-label pilot study.

No study has compared EUS-guided radiofrequency ablation (EUS-RFA) plus systemic chemotherapy (CMT) with CMT alone for unresectable pancreatic ductal adenocarcinoma. This study compared the results of treatment in patients receiving EUS-RFA plus concomitant CMT (group A; n = 14) with those receiving CMT (group B; n = 14) as a pilot study. From July 2017 to August 2018, 4 and 2 patients from groups A and B, respectively, withdrew from the study because of progression of the disease. In total, 10 and 12 patients from groups A and B, respectively, completed the study. All 30 EUS-RFA procedures were successful. Mean maximal tumor diameter before treatment of group A (n = 10) versus B (n = 12) was 62.2 ± 21.0 versus 50.5 ± 22.0 mm, respectively (P = not significant). After treatment, no statistically significant difference in mean maximal tumor diameter was found between both groups. However, in group B, mean maximal tumor diameter was significantly increased from 50.5 ± 22.0 to 56.3 ± 18.7 mm, respectively (P = 0.017). Tumor necrosis occurred in group A versus B at 10 of 10 (100%) versus 6 of 12 (50%) patients, respectively (P = 0.014). After treatment, group A patients could reduce the mean narcotic pain drug dosage at 26.5 mg of morphine equivalent per day (from 63.6 to 37.1 mg, P = 0.022), whereas group B patients could not reduce the dosage of pain-controlled medication. No statistically significant difference in 6-month mortality rate was found. In group A, 1 procedure-related nonsevere adverse event (n = 1 of 30 [3.3%]) occurred in 1 patient (n = 1 of 14 [7.1%]). In this study, the mean tumor diameter of group B was significantly increased after the treatment. Group A had a significantly higher rate of necrosis of tumor and required less narcotic.

Contrast-enhanced harmonic EUS-guided radiofrequency ablation of hepatocellular carcinoma: a new horizon in endohepatology.

Video 1Contrast-enhanced harmonic EUS-guided radiofrequency ablation of hepatocellular carcinoma.

Expanded indication for EUS-guided radiofrequency ablation: management of adrenal tumors

EUS-guided radiofrequency ablation (EUS-RFA) has been performed as an alternative to surgery for the treatment of pancreatic tumors. The promising results obtained using this procedure suggest that the indication for EUS-RFA could be expanded to the management of extrapancreatic tumors. Here, we evaluate the feasibility, efficacy, and safety of EUS-RFA in the treatment of left adrenal tumors. This single-center, prospective study was conducted at Asan Medical Center between January 2016 and November 2021. A total of 11 patients with left adrenal tumors were enrolled in the study. The technical success rate, treatment response, and adverse events were evaluated. EUS-RFA was performed successfully in all patients (technical success rate, 100%). The indications for the procedure were an increase in tumor size (n= 8), and adrenal tumor with adrenal hormone excess (n= 3). After a median of 2 EUS-RFA sessions (range, 1-2), 73% of patients had a complete response, and 27% had a partial response. During follow-up, 5 patients experienced self-limiting mild abdominal pain; no moderate or severe adverse events were reported. EUS-RFA showed high technical feasibility, clinical success, and an acceptable safety profile in the treatment of left adrenal tumors. In patients at high surgical risk, EUS-RFA can be considered as an alternative therapeutic modality to surgery for the treatment of left adrenal tumors.

Risk factors for EUS-guided radiofrequency ablation adverse events in patients with pancreatic neoplasms: a large national French study (RAFPAN study)

EUS-guided radiofrequency ablation (EUS-RFA) has been described as a potentially curative option for solid and cystic pancreatic neoplasms. We aimed to assess the safety and efficacy of pancreatic EUS-RFA in a large study population. A retrospective study retrieving all consecutive patients who underwent pancreatic EUS-RFA during 2019 and 2020 in France was conducted. Indication, procedural characteristics, early and late adverse events (AEs), and clinical outcomes were recorded. Risk factors for AEs and factors related to complete tumor ablation were assessed on univariate and multivariate analyses. One hundred patients (54% men, 64.8 ± 17.6 years old) affected by 104 neoplasms were included. Sixty-four neoplasms were neuroendocrine neoplasms (NENs), 23 were metastases, and 10 were intraductal papillary mucinous neoplasms with mural nodules. No procedure-related mortality was observed, and 22 AEs were reported. Proximity of pancreatic neoplasms (≤1mm) to the main pancreatic duct was the only independent risk factor for AEs (odds ratio [OR), 4.10; 95% confidence interval [CI), 1.02-15.22; P= .04). Fifty-nine patients (60.2%) achieved a complete tumor response, 31 (31.6%) a partial response, and 9 (9.2%) achieved no response. On multivariate analysis, NENs (OR, 7.95; 95% CI, 1.66-51.79; P< .001) and neoplasm size<20mm (OR, 5.26; 95% CI, 2.17-14.29; P< .001) were independently related to complete tumor ablation. The results of this large study confirm an overall acceptable safety profile for pancreatic EUS-RFA. Close proximity (≤1mm) to the main pancreatic duct represents an independent risk factor for AEs. Good clinical outcomes in terms of tumor ablation were observed, especially for small NENs.

Impact of endoscopic ultrasound-guided radiofrequency ablation in managing pancreatic malignancy.

Pancreatic malignancy is still the most lethal gastrointestinal malignancy. It has a very poor prognosis with low survival rate. Surgery is still the main treatment option for pancreatic malignancy. Most patients already have locally advanced and even late stage disease due to non-specific abdominal symptoms. Even though some cases are still suitable for surgical treatment, due to its aggressiveness adjuvant chemotherapy is becoming the standard treatment for controlling the disease. Radiofrequency ablation (RFA) is a thermal therapy that has been used as one of the standard treatments for liver malignancy. It can also be performed intraoperatively. There are several reports on percutaneous RFA treatment for pancreatic malignancy using transabdominal ultrasound and guided by computed tomography scan. However, due to its anatomical location and the risk of high radiation exposure, these methods seem to be very limited. Endoscopic ultrasound (EUS) has been widely used for pancreatic abnormality evaluation due to its ability to detect more accurately, especially small pancreatic lesions, compared to other imaging modalities. By the EUS approach, it is easier to achieve good visualization of tumor ablation and necrosis as the echoendoscope position is closer to the tumor area. Based on studies and a recent meta-analysis, EUS-guided RFA is a promising treatment approach for most pancreatic malignancy cases, but most studies only collected data from a small sample size. Larger studies are needed before clinical recommendations can be made.

Small nonfunctional pancreatic neuroendocrine neoplasms: Time for a step-up treatment approach?

Surgery has been regarded as the only curative treatment for patients with small nonfunctional pancreatic neuroendocrine neoplasms (NF-PNENs) less than 2 cm. Due to the significant adverse event rates of surgery, the European Neuroendocrine Tumor Society issued guidelines favoring surveillance for those patients lacking criteria suggestive of an aggressive disease. Despite the above recommendations, a significant proportion of small NF-PNEN patients still undergo surgery. Recently, several studies have reported the safety and effectiveness of EUS-guided radiofrequency ablation (RFA) for the treatment of small NF-PNENs. The experience with EUS-RFA is, however, limited, but published results indicate a potential role as a minimally invasive alternative treatment for these patients, in particular in those in whom further progression is more probable, before they reach the absolute need for surgery. A step-up approach with EUS-RFA followed by surgery for the failure cases can become a valid option to be validated in clinical studies.

S1066 High 1-Year Survival Rate of UnresecTable Pancreatic Cancer Size Smaller Than 4 cm in Diameter Treated With Concurrent EUS-RFA: An Average Treatment Effect on the Treated Weighted Survival Analysis

Introduction: Treatment of small primary pancreatic ductal adenocarcinoma (PDAC), unresecTable due to of blood vessel involvement or distant metastasis, relies on systemic therapy only. We hypothesized that concurrent EUS-guided radiofrequency ablation (EUS-RFA) might control the primary tumor and improve patients’ outcomes. Methods: A prospective series of unresecTable PDAC patients with primary tumor size ≤4 cm who underwent EUS-RFA using a 19-gauge RFA needle (STARmed Koyang, Korea) from Jan 2017 – Jan 2022 were compared with matched historical controls. A propensity score was calculated using tumor size, staging, age adjusted Charleston Comorbidity Index (CCI), Chemotherapy regimen received, and interactions between CCI regimen and staging. This was used to reweight observations so covariate distribution in the chemotherapy only group equalled that of the RFA group (Average Treatment effect on the Treated weights). We used the VIVA combo RF system with an energy of 50 Watts and impedance of 100 Ohms. Chemotherapy was given if the patients were deemed tolerable by oncologists. The patients were followed for at least 12 months to see the survival rates. Results: 46 patients comprised of 11 patients in EUS-RFA group and 35 patients in control group were included in the analysis. The mean (SD) age was 63 (13.5) years in the RFA group and 68 (8.1) years in control group. Characteristics of patients, along with the standard mean differences before and after weighting are show in in Table. Median weighted survival was 14 months in the RFA group versus 6.1 months in the controls. The adjusted survival probability at 6 and 12 months was 73% and 64% in the EUS-RFA group, versus 69% and 17% in the controls. The hazard ratio (HR) for death was 0.38 (95%CI 0.17 to 0.84); p=0.016 in the RFA group versus the controls. Median weighted time to progression was 6.1 in the RFA group versus 3.9 months in the controls. The adjusted progression-free survival at 6 and 12 months in the EUS-RFA group were 55% and 36%, versus 28% and 4% in the controls; the HR for progression was 0.57 (95%CI 0.36 – 1.26); p = 0.16 in the RFA group versus controls. The adverse events were only mild abdominal pain which were observed in 8.3% of total RFA operations. Conclusion: In patients PDAC with primary lesions ≤4 cm that cannot be cured by surgery, EUS-RFA combined with chemotherapy resulted in improved survival and progression free survival with minimal adverse events.Figure 1.: Treatment outcomes compared RFA group with control group Table 1. - Baseline characteristics of the enrolled patients *Data are mean (SD) or n(%) as appropriate. Percentages are rounded to 1 decimal place and may not equal 100% Characteristic Raw (unweighted) After weighting Prospective cases (n=11) Historical controls (n=35) Prospective cases (n=11) Historical controls (n=35) Standardized mean difference p-value Mean age (years) 63 (13.5) 68 (8.1) Female sex, n(%) 9 (81.8) 22 (62.9) Mean CCI score 2.91 (2.4) 2.89 (1.3) 2.91 2.94 -0.055 0.98 Tumor diameter (cm) 3.25 (0.51) 3.10 (0.58) 3.25 3.25 0.008 0.90 Regimen, n(%) None 3 (27.3) 6 (17.1) 27.3 26.3 0.022 0.96 First-line 3 (27.3) 16 (45.7) 27.3 27.0 0.005 0.99 Second-line 5 (45.5) 13 (37.1) 45.5 46.7 -0.025 0.96 Staging Stage III 6 (54.6) 24 (68.6) 54.5 56.6 0.021 0.97 Stage IV 5 (45.5) 11 (31.4) 45.5 43.4 -0.021 0.97

EUS-guided radiofrequency ablation of pancreatic/peripancreatic tumors and oligometastatic disease: an observational prospective multicenter study.

Background and study aims Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) is an emerging and minimally invasive technique that seems promising for treatment of focal pancreatic and peripancreatic lesions. Our aim was to prospectively evaluate the feasibility, safety, and technical and clinical success of pancreatic and extra-pancreatic EUS-RFA. Patients and methods We prospectively collected clinical and technical data for all patients who underwent EUS-RFA at two Belgian academic centers from June 2018 to February 2022. Feasibility, adverse events (AEs), and follow-up were also assessed. Results Twenty-nine patients were included, accounting for 35 lesions: 10 non-functioning neuroendocrine tumors (29 %), 13 pancreatic insulinomas (37 %), one adenocarcinoma (3 %), and 11 intra-pancreatic and extra-pancreatic metastatic lesions (31 %). Technical success was achieved in 100 % of cases, with a median of three power applications per lesion (interquartile range 2). The majority of patients (59 %) presented no collateral effects, three (10.3 %) developed non-severe acute pancreatitis, and four (14 %) had mild abdominal pain. At 6 months follow-up (n = 25), 36 % of patients showed radiological complete response, 16 % presented a significant partial response and 48 % showed < 50 % decrease in diameter. At 12 months (n = 20), 30 % showed complete necrosis and 15 % > 50 % decrease in diameter. Hypoglycemia related to insulinoma was immediately corrected in all 13 cases, with no recurrence during follow-up. Conclusions EUS-RFA is feasible, safe, and effective for treatment of pancreatic and peripancreatic tumors. Larger and longer multicenter prospective studies are warranted to establish its role in management of focal pancreatic lesions and oligometastatic disease. Symptomatic insulinoma currently represent the best indication.

An update on EUS-guided ablative techniques for pancreatic cystic lesions.

Pancreatic cystic lesions (PCLs) are increasingly being recognized due to improvements and widespread use of cross-sectional imaging. With an estimated prevalence of 15% in general population, incidentally discovered PCLs represent a dilemma in management. While pancreatectomies offer a chance of cure, the morbidity is considerable in patients with high surgical risks. More recently, EUS-guided approaches for cyst ablation are being offered in clinical trials for the management of PCLs. EUS-chemoablation studies have progressed from first investigating safety and efficacy of EUS-guided alcohol lavage to single-agent paclitaxel ablation. Recent studies have shown that alcohol lavage may not be required, and long-term resolution can be achieved by chemoablation alone. EUS-guided lauromacrogol ablation and EUS-guided radiofrequency ablation (RFA) are new techniques that have shown promising results in a few small studies. Overall, the current literature suggests that EUS-guided paclitaxel ablation has better cyst resolution rates compared to other existing minimally invasive techniques including ethanol injection, lauromacrogol ablation, or RFA. This article will review EUS-guided PCL ablation approaches and future directions the field is headed into.

Current role of endoscopic ultrasound in the diagnosis and management of pancreatic cancer.

Endoscopic ultrasound (EUS) has emerged as an invaluable tool for the diagnosis, staging and treatment of pancreatic ductal adenocarcinoma (PDAC). EUS is currently the most sensitive imaging tool for the detection of solid pancreatic tumors. Conventional EUS has evolved, and new imaging techniques, such as contrast-enhanced harmonics and elastography, have been developed to improve diagnostic accuracy during the evaluation of focal pancreatic lesions. More recently, evaluation with artificial intelligence has shown promising results to overcome operator-related flaws during EUS imaging evaluation. Currently, an appropriate diagnosis is based on a proper histological assessment, and EUS-guided tissue acquisition is the standard procedure for pancreatic sampling. Newly developed cutting needles with core tissue procurement provide the possibility of molecular evaluation for personalized oncological treatment. Interventional EUS has modified the therapeutic approach, primarily for advanced pancreatic cancer. EUS-guided fiducial placement for local targeted radiotherapy treatment or EUS-guided radiofrequency ablation has been developed for local treatment, especially for patients with pancreatic cancer not suitable for surgical resection. Additionally, EUS-guided therapeutic procedures, such as celiac plexus neurolysis for pain control and EUS-guided biliary drainage for biliary obstruction, have dramatically improved in recent years toward a more effective and less invasive procedure to palliate complications related to PDAC. All the current benefits of EUS in the diagnosis and management of PDAC will be thoroughly discussed.

EUS-guided radiofrequency and ethanol ablation for pancreatic neuroendocrine tumors: A systematic review and meta-analysis.

ABSTRACTEUS-guided radiofrequency ablation (RFA) and ethanol ablation (EA) for pancreatic neuroendocrine tumors (PNETs) have recently been reported with good outcomes. We performed a systematic review and meta-analysis to evaluate the comparative effectiveness and safety of EUS-RFA and EUS-EA in the treatment of PNETs. A comprehensive search of multiple databases (through October 2020) was performed to identify studies that reported outcomes of EUS-RFA and EUS-EA of PNETs. Outcomes assessed included clinical success, technical success, and adverse events (AEs). A total of 181 (100 EUS-RFA, 81 EUS-EA) patients (60.7 ± 9.2 years) with 204 (113 EUS-RFA, 91 EUS-EA) PNETs (mean size 15.1 ± 4.7 mm) were included from 20 studies. There was no significant difference in the rates of technical success (94.4% [95% confidence interval (CI): 88.5–97.3, I2 = 0] vs. 96.7% [95% CI: 90.8–98.8, I2 = 0]; P = 0.42), clinical success (85.2% (95% CI: 75.9–91.4, I2 = 0) vs. 82.2% [95% CI: 68.2–90.8, I2 = 10.1]; P = 0.65), and AEs (14.1% [95% CI: 7.1–26.3, I2 = 0] vs. 11.5% [95% CI: 4.7–25.4, I2 = 63.5]; P = 0.7) between EUS-RFA and EUS-EA, respectively. The most common AE was pancreatitis with the rate of 7.8% and 7.6% (P = 0.95) for EUS-RFA and EUS-EA, respectively. On meta-regression, the location of PNETs in head/neck of pancreas (P = 0.03) was a positive predictor of clinical success for EUS-RFA. EUS-RFA and EUS-EA have similar effectiveness and safety for PNETs ablation. Head/neck location of PNETs was a positive predictor for clinical success after EUS-RFA.

Clinical outcomes of EUS-guided radiofrequency ablation for unresectable pancreatic cancer: A prospective observational study.

Background and Objectives:EUS-guided radiofrequency ablation (EUS-RFA) has been increasingly used for the treatment of pancreatic neoplasms. The role of EUS-RFA in the management of pancreatic cancer has not yet been elucidated. This study aimed to evaluate the survival impact of EUS-RFA in unresectable pancreatic cancer.Methods:Twenty-two patients (n = 14, locally advanced unresectable; n = 8, metastatic) with unresectable pancreatic cancer underwent EUS-RFA combined with subsequent chemotherapy between May 2016 and June 2019. Survival outcomes including overall survival (OS) and progression-free survival (PFS) were evaluated.Results:EUS-RFA was successful in all patients. The median number of RFA sessions was 5 (interquartile range, [IQR], 3.25–5.75). After successful EUS-RFA, subsequent gemcitabine-based chemotherapy was performed. Early procedure-related adverse events occurred in 4 out of 107 sessions (3.74%), including peritonitis (n = 1) and abdominal pain (n = 3). During follow-up over a median of 21.23 months (IQR, 10.73–27.1), the median OS and PFS were 24.03 months (95% confidence interval [CI], 16–35.8) and 16.37 months (95% CI, 8.87–19), respectively.Conclusions:EUS-RFA is technically feasible and safe for the management of unresectable pancreatic cancer. EUS-RFA combined with systemic chemotherapy may be associated with favorable survival outcomes. Further larger-scale prospective comparative study is required to confirm these findings.