Comparison of modified wet suction technique and dry suction technique in endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for solid lesions: study protocol for a randomized controlled trial

Study Protocol for a Prospective Self-Controlled Trial on Success in Meeting Comprehensive Genomic Profiling Analysis Criteria for Specimens Obtained by Endoscopic Ultrasound-Guided Tissue Acquisition Using a 19G Needle from Primary and Metastatic Lesions in Pancreatic Cancer with Metastatic Lesions: The PRIMATE Study

EUS-TA in unresectable pancreatic cancer requires not only a tissue diagnosis but also tissue collection in anticipation of comprehensive genomic profiling. However, the optimal puncture target remains controversial. Therefore, the Primary and Metastatic Lesions in Pancreatic Cancer (PRIMATE) study was designed to clarify the optimal target by comparing the success rates for meeting OncoGuide NCC Oncopanel (NOP) analysis criteria on pre-check primary and metastatic lesion specimens obtained during the same EUS-TA session in patients with invasive pancreatic ductal adenocarcinoma. In this ongoing prospective study, two specimens, each from primary and metastatic lesions, are obtained by EUS-TA (typically using a 19G fine-needle biopsy needle) in patients with invasive pancreatic ductal adenocarcinoma. The primary endpoint is the proportion of EUS-TA specimens that meet NOP analysis criteria during pre-check (i.e., tumor cellularity of ≥20% and a tissue area of ≥4 mm2), which are then compared between primary and metastatic lesions. This study has been approved by the National Cancer Center Institutional Review Board (Research No. 2022-168). The results of this study will be reported at an international conference and published in an international peer-reviewed journal. The trial registration number is UMIN 000048966.

Endoscopic ultrasound-guided fine-needle aspiration for gastrointestinal subepithelial lesions

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the first-choice procedure for obtaining pathological tissue samples from gastrointestinal (GI) subepithelial lesions (SELs). However, its diagnostic accuracy is lower than that for pancreatic masses owing to puncture difficulty and the need for immunostaining for definitive diagnosis. The advent of fine-needle biopsy needles, which have become well known in recent years, improves the diagnostic accuracy of EUS-FNA for GI SELs. The forward-viewing echoendoscope and rapid on-site evaluation (ROSE) have also helped to improve diagnostic accuracy. Furthermore, in facilities where ROSE is not available, endosonographers perform a macroscopic on-site evaluation. With these procedural innovations, EUS-FNA is now performed aggressively even for SELs smaller than 20 mm. The incidence of procedure-related adverse events such as bleeding and infection is low, and thus, EUS-FNA can be safely performed to diagnose SELs.

Methods to increase the diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration for solid pancreatic lesions: An updated review

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a means to procure adequate specimens for histological and cytologic analysis. The ideal EUS-FNA should be safe, accurate, and have a high sample adequacy rate and low adverse events rate. In recent years, many guidelines and trials on EUS-FNA have been published. The purpose of this article is to provide an update on the influence of some of the main factors on the diagnostic efficiency of EUS-FNA as well as a rare but serious complication known as needle tract seeding.

Comparing fine needle biopsy techniques in solid pancreatic lesions: A prospective randomized study

INTRODUCTION

Endoscopic ultrasound-guided fine-needle biopsies (EUS-FNB) are the best technique for sampling solid pancreatic lesions. However, the most appropriate biopsy technique has not been standardized using Fine Needle Biopsy (FNB) needles. The aim of this work was to identify the best biopsy technique to achieve the best tissue integrity and cause the least blood contamination.

MATERIAL AND METHODS

Patients ≥18 years of age with solid pancreatic lesions who underwent EUS-FNB at our institution from January 2020 to May 2021 were consecutively selected. Three passes were performed with each of the threee techniques to obtain tissue: suction with 10 ml of vacuum, capillary, and wet. An independent pathologist evaluated the received tissue integrity and the degree of blood contamination of each sample according to scales.

RESULTS

Seventy-five patients were recruited for our study. A superior tissue integrity was observed using the wet-suction technique in lesions located in the body and/or tail of the pancreas, and an average score of 4.40 (p = 0.027) was assigned for this technique. Regarding the contamination of the sample in the whole cohort, the simple-suction technique shown a higher contamination, 1.55 (p < 0.001). There was no statistically significant difference among the techniques when evaluating tissue integrity or contamination in lesions larger or smaller than 3 cm.

CONCLUSION

When performing EUS-FNB for solid pancreatic lesions located in the head/uncinated process, the three methods provided similar diagnostic yields. The wet-suction technique had a higher score in tissue integrity when lesions were located in the body and/or tail of the pancreas.

EUS-guided FNAC in intra-abdominal lesions: Technique of tissue acquisition, ancillary testing, pearls and perils, and prospects

Endoscopic ultrasound enables visualization of lesions within and in the vicinity of the gastrointestinal tract. Endoscopic ultrasound guided fine needle aspiration cytology (EUS-FNAC) helps in targeting various luminal and extraluminal lesions both diagnostically and therapeutically. Various intra-abdominal organs amenable to EUS-FNA include the gastrointestinal tract (GIT), pancreas, kidney, adrenal gland, liver, bile duct, gallbladder, spleen, and lymph nodes. EUS-FNAC is mostly done for pancreatic and intra-abdominal lymph nodal lesions. In the present review, we have discussed various aspects of EUS-FNAC.

Diagnostic and Prognostic Values of KRAS Mutations on EUS-FNA Specimens and Circulating Tumor DNA in Patients With Pancreatic Cancer

INTRODUCTION

The ability of carbohydrate antigen 19-9 (CA19-9) to differentiate pancreatic cancer from other benign pancreatic lesions is unsatisfactory. This study explored the diagnostic value of KRAS gene mutations and plasma circulating tumor DNA (ctDNA) in patients with pancreatic cancer.

METHODS

The prospective cohort study comprised 149 consecutive patients with solid pancreatic lesions who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). KRAS subtype mutations were analyzed by digital droplet PCR (ddPCR) in EUS-FNA histopathology tissue samples, and blood samples were sent for plasma ctDNA analysis. The final diagnosis was based on surgical resection pathology or follow-up for at least 2 years.

RESULTS

Adding KRAS mutation ddPCR increased the sensitivity and accuracy of EUS-FNA from 71.4% to 91.6% (P < 0.001) and 75.8% to 88.6% (P < 0.001), respectively. By comparison, the sensitivities of circulating biomarkers ctDNA and CA19-9 were only 35.2% and 71.2%. The area under the curve of the receiver operating characteristic curve (AUC) of EUS-FNA and KRAS ddPCR combination was >0.90 for distinguishing pancreatic cancer from benign lesions, whereas the AUC of EUS-FNA and CA19-9 combination was 0.83. The median survival time was significantly shorter in patients with G12D KRAS mutations than that in patients with other mutations (180 vs 240 days, P < 0.001).

DISCUSSION

FNA tissue sample KRAS mutation analysis in tissues significantly improves the diagnostic accuracy of cyto/histopathological evaluation in EUS-FNA samples. The combination of EUS-FNA and tissue sample KRAS ddPCR provided a more accurate method for pancreatic cancer diagnosis, superior to the combination of EUS-FNA and CA19-9/ctDNA. G12D KRAS mutations in pancreatic cancer were independently associated with poor overall survival.

Comparison between modified wet suction and dry suction technique for endoscopic ultrasound-guided fine-needle biopsy in pancreatic solid lesions

BACKGROUND AND AIM

Although endoscopic ultrasound-guided fine-needle biopsy is widely applied, there is no clear consensus on the optimal biopsy technique. We described a modified wet suction technique (MWEST) with the aim to compare the efficacy and safety between MWEST and the dry suction technique (DST).

METHODS

In this prospective, randomized, crossover, single-blinded study, patients with suspected pancreatic malignancy were randomized to the DST (group A) or MWEST (group B) for the first pass, and the two techniques were performed alternately. The primary outcome was the comparison of specimen adequacy and diagnostic yield between the techniques. Secondary outcomes included the macroscopic visible core length, blood contamination of specimens, and adverse events of both techniques.

RESULTS

From January 2019 to September 2019, 216 passes were performed in 50 patients. The specimen adequacy was significantly higher in "per-lesion" (P = 0.026), "per-pass" (cytology: P = 0.034; histology: P = 0.042), and first-pass analysis (P = 0.034) for MWEST than for DST. In diagnostic yield, MWEST showed significantly superior histological yield (P = 0.014) and first-pass analysis (κ: MWEST: 0.743 and DST: 0.519) compared with DST. The median macroscopic visible core lengths were 8 mm (interquartile range: 3.25-15 mm) and 10 mm (interquartile range: 5.25-15 mm) for DST and MWEST, respectively (P = 0.036). Blood contamination was significantly more serious in DST than in MWEST (cytology: P = 0.021; histology: P = 0.042).

CONCLUSIONS

Endoscopic ultrasound-guided fine-needle biopsy with MWEST resulted in significantly better quality of specimen, histological, and first-pass diagnostic yields and comparable safety compared with the DST. MWEST is preferred for endoscopic ultrasound-guided fine-needle biopsy in pancreatic solid lesions.

Amyloid-Rich Pancreatic Neuroendocrine Tumors: a Potential Diagnostic Pitfall in Endoscopic Ultrasound-Guided Fine Needle Aspiration Cytology (EUS-FNAC)

Pancreatic neuroendocrine tumors (PanNETs) are rare neoplasms that include even rarer variants that may pose different diagnostic problems, especially in fine needle aspiration cytology (FNAC). We describe the diagnostic clues of the amyloid-rich variant of PanNETs in endoscopic ultrasound (EUS)-guided fine needle aspiration cytology (EUS-FNAC). Three cases of PanNETs with an amyloid-rich stromal component were retrieved and retrospectively reviewed. For every case, the pancreatic lesion was investigated by a EUS-FNAC procedure. The final diagnosis was supported by immunocytochemistry and Congo red staining. All cases had similar EUS-FNAC features: neoplastic cells were entrapped in an eosinophilic, homogeneous dense and amorphous matrix. The neuroendocrine nature was confirmed by immunoexpression of synaptophysin and chromogranin A, while the amorphous stroma was characterized as amyloid based on positive Congo red staining. Regarding the hormonal profile, no insulin or proinsulin reactivity was observed, but all cases were diffusely positive for amylin. The diagnosis of uncommon variants of PanNETs, such as the amyloid-rich, is challenging especially in EUS-FNAC procedures because of a unique and misleading morphology, potentially mimicking fibrotic conditions and amyloid deposition within systemic amyloidosis. In cytology specimens, the presence of amorphous material requires amyloid deposition to be considered in the differential diagnosis of pancreatic neoplasms with neuroendocrine phenotype.

A Pilot Randomized Crossover Trial of Wet Suction and Conventional Techniques of Endoscopic Ultrasound-Guided Fine-Needle Aspiration for Upper Gastrointestinal Subepithelial Lesions

Methods

Twenty-six patients with UGI-SELs indicated for EUS-FNA were randomly assigned to the dry-first arm using the dry technique for the first two passes or the wet-first arm using the wet technique for the first two passes using a cross-over design with a ratio of 1 : 1. The primary endpoint was the cellularity score of the EUS-FNA specimens rated on a 4-point scale (0-3). The secondary endpoints were the factors influencing cellularity in each suction technique.

Results

The mean cellularity score was 1.65 ± 1.20 for the wet technique and 2.00 ± 0.98 for the dry technique (p = 0.068). Logistic regression analysis showed that higher cellularity may be related to the final diagnosis of gastrointestinal stromal tumors in the dry technique and the SEL location in the upper stomach in the wet technique.

Conclusion

The wet EUS-FNA technique failed to show a potential for improved cellularity of specimens compared to the dry technique for UGI-SELs.

Mediastinal granular cell tumor diagnosed with endoscopic ultrasound-guided fine needle aspiration via a modified technique based on wet suction: A case report and literature review

Granular cell tumor (GCT) represents a less frequently seen tumor originating from Schwann cells. Although GCT develops in various locations in the human body, GCT of the mediastinum is extremely uncommon. A case of mediastinal GCT diagnosed by aspiration using a fine needle assisted by endoscopic ultrasound (EUS-FNA) via a modified technique based on wet suction was reported. An asymptomatic 28-year-old man was referred for assessment of a mass in the mediastinum that was found incidentally via chest computed tomography (CT) at health screening. EUS demonstrated a hypoechoic lesion with a distinct boundary, which was derived from the upper posterior mediastinum and partly located close to the posterior wall of the esophagus. Therefore, EUS-FNA with a modified wet suction technique was performed to harvest adequate specimens for the diagnosis of GCT. Minimally invasive tumor removal was performed, and histological examination of the specimen harvested surgically verified GCT, consistent with histological findings of the specimen obtained by EUS-FNA. The case highlights that a good accuracy of histological diagnosis and specimen quality are achieved for the modified wet-suction technique in EUS-FNA, and a preoperative diagnosis of mediastinal GCT can be made with certainty.

Diagnostic efficacy of three suction techniques for endoscopic ultrasound-guided fine-needle biopsy of solid pancreatic lesions: protocol for a multicenter randomized cross-over clinical trial

BACKGROUND

How suction technique affects endoscopic ultrasound-guided tissue acquisition (EUS-TA) remains unclear. A standardized protocol is currently lacking, with most previous studies being restricted to EUS-guided fine-needle aspiration (EUS-FNA). The research related to EUS-guided fine-needle biopsy (EUS-FNB) is sparse.

AIMS

The aim of this study is to evaluate the diagnostic efficacy, cellularity, tissue acquisition, blood contamination and adverse event rate of three common suction techniques (standard suction, slow-pull, and wet suction) used for EUS-FNB of solid pancreatic masses.

METHODS

This is a multicenter single-blind randomized cross-over superiority trial. A total of 300 patients with suspected pancreatic malignancy will be enrolled from digestive endoscopic centers at five large tertiary hospitals in China. All three suction techniques will be performed on each patient using a 25G ProCore needle, with the sequence of suction techniques determined by randomization. Cytological and histological specimens obtained with each of the three techniques will be assessed independently. Outcomes among the three suction techniques will be compared.

DISCUSSION

To the best of our knowledge, this is the largest multicenter randomized cross-over trial designed to determine the optimal suction technique for the diagnosis of solid pancreatic masses. This study may contribute to standardizing the suction technique for EUS-FNB.

An international, multi-institution survey on performing EUS-FNA and fine needle biopsy

Background and Objectives

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and fine needle biopsy (FNB) are effective techniques that are widely used for tissue acquisition. However, it remains unclear how to obtain high-quality specimens. Therefore, we conducted a survey of EUS-FNA and FNB techniques to determine practice patterns worldwide and to develop strong recommendations based on the experience of experts in the field.

Methods

This was a worldwide multi-institutional survey among members of the International Society of EUS Task Force (ISEUS-TF). The survey was administered by E-mail through the SurveyMonkey website. In some cases, percentage agreement with some statements was calculated; in others, the options with the greatest numbers of responses were summarized. Another questionnaire about the level of recommendation was designed to assess the respondents' answers.

Results

ISEUS-TF members developed a questionnaire containing 17 questions that was sent to 53 experts. Thirty-five experts completed the survey within the specified period. Among them, 40% and 54.3% performed 50-200 and more than 200 EUS sampling procedures annually, respectively. Some practice patterns regarding FNA/FNB were recommended.

Conclusion

This is the first worldwide survey of EUS-FNA and FNB practice patterns. The results showed wide variations in practice patterns. Randomized studies are urgently needed to establish the best approach for optimizing the FNA/FNB procedures.

Endoscopic ultrasonography in pancreatic diseases: advances in tissue acquisition

Background and study aims  Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) improved the diagnostic performance and upgraded the role of endoscopic ultrasonography (EUS) into an interventional modality, able to guide patient management and treatment.This review aimed to highlight the advances, emerging practices, procedural techniques and technological innovations in EUS tissue acquisition in pancreatic diseases. Methods  A thorough review of the literature was performed using PubMed to identify articles that describe techniques, advances, and practices in EUS tissue acquisition in gastrointestinal diseases. Conclusion  Since the first EUS-FNA procedure, EUS guided-tissue acquisition has been evolving continuously. Development of needles with innovative tip design enabled procurement of larger samples with preserved histological architecture. Moreover, sampling techniques and complementary methods, such as contrast harmonic imaging and EUS-elastography, have been introduced in an effort to improve diagnostic performance and sample adequacy.

Efficacy of 3 fine-needle biopsy techniques for suspected pancreatic malignancies in the absence of an on-site cytopathologist

BACKGROUND AND AIMS

EUS-guided fine-needle aspiration/biopsy (EUS-FNA/B) has a high diagnostic accuracy for pancreatic tumors. Most reports have focused on the diagnostic yield of cytology or histology; the ability of various FNA/B techniques to obtain an adequate mass of cells or tissue has rarely been investigated.

METHODS

Patients with suspected pancreatic malignancy underwent EUS-FNB using a 22-gauge ProCore needle by either the stylet slow-pull-back technique (group A), conventional negative suction after stylet removal (group B), or non-suction after stylet removal (group C) in the absence of an on-site cytopathologist. The adequacy of the 3 techniques based on the diagnostic yield, cellularity, blood contamination, and core-tissue acquisition was evaluated.

RESULTS

A total of 50 patients (27 males) were analyzed. The mean tumor size was 21 to 40 mm in 54%. The rate of a good or excellent proportion of cellularity was highest in group A compared with groups B and C (72% vs 60% vs 50%, P = .049). A >25% rate of blood contamination was more prevalent in group B (30% vs 42% vs 10%, P = .009). The rate of adequate core-tissue acquisition was not different (52% vs 34% vs 50%, P = .140). Based on the multivariate generalized estimation equation, the stylet slow-pull-back technique and a tumor size >40 mm were favorable factors for diagnostic adequacy.

CONCLUSIONS

The stylet slow-pull-back technique might enable acquisition of tissue and assessment of cellularity for the diagnosis of pancreatic tumors suspected to be malignant. (Clinical trial registration number: KCT0002190.).

Impact of calcifications on diagnostic yield of endoscopic ultrasound-guided fine-needle aspiration for pancreatic ductal adenocarcinoma

INTRODUCTION

Chronic calcific pancreatitis (CCP) is a major risk factor for pancreatic ductal adenocarcinoma (PDAC) and is common in southern India. Endoscopic ultrasound fine-needle aspiration (EUS-FNA) is useful for tissue acquisition in patients with solid pancreatic lesions. Multiple factors may affect the diagnostic yield of FNA samples. The present study was performed to assess the impact of pancreatic calcifications on the diagnostic yield of EUS-FNA in PDAC.

METHODS

All patients with confirmed PDAC from January 2013 to December 2017 were included. CCP was diagnosed based on typical imaging characteristics with or without evidence of pancreatic insufficiency along with surgical histopathology reports showing features of chronic pancreatitis. The diagnostic yield and adequacy of cellularity were  assessed by a pathologist who was blinded and were compared between the two groups: group 1: PDAC patients with no evidence of CCP and, group 2: PDAC patients with CCP.

RESULTS

A total of 122 patients were included in the study. The diagnostic yield was lower in patients in group 2 (n = 42, 25 [59.52%]) as compared to those in group 1 (n = 80, 63 [78.75%]) (p-value = 0.01). On multivariate analysis, only the presence of calcifications was found to have an independent association with diagnostic yield (odds ratio 3.83 [95% confidence interval 1.22-11.9]).

CONCLUSIONS

CCP had a significant impact on the diagnostic yield of EUS-FNA for pancreatic adenocarcinoma. Novel techniques and newer technology that may mitigate the negative effect of calcification on diagnostic yield of EUS-FNA in patients with CCP.