Conclusions regarding the suction techniques of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) remain controversial. This study aimed to compare the diagnostic accuracy of the dry suction vs wet suction technique in solid pancreatic lesions (SPLs) and determine the optimal number of passes for EUS-FNB.

This investigation was conducted as a multicenter, randomized, controlled, noninferiority trial. Patients with SPLs were randomly allocated to receive either the dry or wet suction technique. The primary outcome was diagnostic accuracy. The secondary outcomes included sensitivity, specificity, optimal number of needle passes, specimen quality, procedure time, and adverse events.

Of the 200 patients, 193 were included in the final analysis, with 96 in the dry suction group and 97 in the wet suction group. The diagnostic accuracies were 97.92% and 96.91% in the dry and wet groups, respectively, with a 1.01% difference between the study groups (2-sided 95% CI, -3.47% to 5.48%, P = 0.659). The overall adverse event rate was 2.6%. No significant differences were observed in sample adequacy (98.9% vs 98.9%, P = 1) or blood contamination ( P = 0.796). Regarding procedure time, there was no statistical difference (18.68 ± 8.03 minutes vs 19.36 ± 8.89 minutes, P = 0.626); however, more procedural steps were required in the wet suction technique. No significant difference was found between the cumulative diagnostic accuracy of each needle (first pass 93.78% vs second pass 95.34% vs third pass 97.41%, P = 0.225).

The dry suction technique is noninferior to the wet suction technique for EUS-FNB in SPLs. In the absence of rapid on-site evaluation, only one pass was required to achieve more than 90% diagnostic accuracy ( ClinicalTrial.gov number NCT05549856).

The negative pressure selectable for the wet-suction technique remains uncertain. The aim was to investigate the quality of sampling and diagnostic accuracy with solid lesions by 5 mL and 10 mL negative pressure with wet-suction techniques.

This is a single-center, crossover, randomized controlled trial conducted with a random sampling technique. In all, 160 patients consecutively undergoing EUS-FNA for solid lesions were randomized in a ratio of 1:1 into 2 groups, the 5 mL and 10 mL negative pressure wet-suction group. The main outcome was to compare the sample quality between the 2 groups. The secondary outcome was to compare the histologic and cytologic diagnostic accuracy of solid lesions.

Pancreatic (n=129) and nonpancreatic (n=27) lesions from 156 lesions were examined. The sample quality concluding cellularity, adequacy, integrity, and blood contamination were comparable between the 2 groups. However, in subgroup analysis, we found 19G FNA provided more integrity of specimen in 5 mL than in 10 mL group (100% vs. 82.9%, P =0.025). In contrast, this benefit was not noteworthy in the 22G FNA subgroup. And there was no statistically significant in histologic (87.82% vs. 87.18%, P =1.000) and cytologic (78.85% vs. 80.77%, P =0.778) accuracy between 5 mL and 10 mL groups.

When using the wet-suction technique, 5 mL and 10 mL negative pressure offer equivalent sample quality and diagnostic accuracy. However, the 19G FNA can obtain better sample quality with 5 mL negative pressure than 10 mL negative pressure.

In solid pancreatic lesions (SPLs), we compared the diagnostic efficacy of a 19G fine-needle aspiration (FNA) needle and a 22G ProCore fine-needle biopsy (FNB) needle, We also compared the specimen quality between the standard suction (SS) technique and heparinized wet-suction (HWS) technique.

All cases of endoscopic ultrasound-guided tissue acquisition (EUS-TA) by 19G FNA or 22G FNB for SPLs in a single-centre hospital were retrospectively reviewed. The diagnostic yield was compared between the 19G and 22G groups. Univariate and multivariate logistic regression analyses were used to identify optimal factors for a correct histological diagnosis. We also examined tissue integrity, the length of the tissue cores, and the rate of blood cell contamination between the SS and HWS groups.

One hundred seventy-one and sixty-three patients were included in the comparisons of needle types and suction techniques, respectively. The 19G group had higher histological diagnosis rates compared to the 22G group for the first pass (87.8% vs. 70.4%, p = 0.005), the second pass (82.2% vs. 65.4%, p = 0.012), the first two passes (90.0% vs. 72.8%, p = 0.004), and the final diagnosis (91.1% vs. 79%, p = 0.025). Through macroscopic on-site evaluation, a significantly higher proportion of patients in the 22G group required a third needle pass compared to the 19G group (88.9% vs. 67.8%, p = 0.002). The total procedure time was shorter in the 19G group than in the 22G group (p < 0.001). The HWS group showed superiority over the SS group in terms of the total length of tissue cores (p < 0.001) and the total length of white tissue cores (p = 0.005). The HWS group, compared to the SS group, can enhance the tissue integrity (p = 0.024) and reduce blood cell contamination (p = 0.040) during the first needle pass. There was no significant difference in complication rates between the needle puncture groups (p = 0.770) or the aspiration technique groups (p = 0.654).

Compared to the 22G FNB needle, endoscopists should consider using the 19G FNA needle when appropriate. Furthermore, the use of the HWS technique for the first pass is recommended to improve specimen quality.

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.

EUS-guided tissue acquisition (EUS-TA) is the preferred method to acquire pancreatic cancer (PC) tissues. The factors associated with false-negative outcomes and inadequate samples should be explored to gain an understanding of EUS-TA.

The patients who underwent EUS-TA for suspected solid PC but whose results were false-negative were analyzed. The PC patients who underwent EUS-TA with true-positive results on the first day of every month during the study period were selected as the control group. The factors influencing diagnostic accuracy and sample adequacy were explored.

From November 2017 to January 2022, 184 patients were included in the false-negative group, and 175 patients were included in the control group. Multivariate logistic regression demonstrated that the recent acute pancreatitis [odds ratio (OR): 0.478, 95% confidence interval (CI): 0.250-0.914, P = 0.026] and high echo component within the tumor (OR: 0.103, 95% CI: 0.027-0.400, P = 0.001) were independently associated with false-negative EUS-TA results. Meanwhile, using fine-needle biopsy (FNB) needles (OR: 2.270, 95% CI: 1.277-4.035, P = 0.005), more needle passes (OR: 1.651,95% CI: 1.239-2.199, P = 0.005), large tumor size (OR: 1.053, 95% CI: 1.029-1.077, P < 0.001), and high CA-19-9 level (OR: 1.001, 95% CI: 1.000-1.001, P = 0.019) were independently associated with true-positive EUS-TA outcomes. Three needle passes are needed to achieve optimal EUS-TA outcomes. Tumor location in the body/tail (OR: 1.38, 95% CI: 1.01-1.72; P = 0.04), needle passes ≥3 (OR: 1.90; 95% CI: 1.22-2.56; P < 0.001), and using the FNB needle (OR: 2.10; 95%: 1.48-2.85; P < 0.001) were independently related to sample adequacy.

Numerous factors were identified to be associated with the diagnostic accuracy and sample adequacy of EUS-TA.

Studies have shown that the wet suction technique in endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) generates better histological diagnostic accuracy and specimen quality than the dry suction technique. However, conclusions of wet suction on the diagnostic accuracy of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) are still controversial. Besides, the optimal number of passes for EUS-FNB has not been determined. We aimed to design a large multicenter randomized trial to compare the diagnostic accuracy of dry suction versus wet suction technique in solid pancreatic lesions (SPLs) using 22G Franseen needles and determine the optimal number of passes required for EUS-FNB.

This is a multi-center open-label, randomized controlled non-inferiority trial with two parallel groups. Two hundred patients with SPLs will undergo EUS-FNB using 22G Franseen needles in 4 tertiary hospitals in China and will be randomly assigned to the dry suction group and wet suction group in a ratio of 1:1. The primary endpoint is diagnostic accuracy. Secondary endpoints include the optimal number of needle passes, sensitivity, specificity, specimen quality, cytological diagnoses, time of the procedure, and incidence of complications.

This study has been designed to determine (i) whether EUS-FNB using 22G Franseen needle with dry suction is non-inferior to wet suction in terms of diagnostic accuracy and (ii) the optimal number of passes during EUS-FNB of SPLs using 22G Franseen needle.

ClinicalTrials.gov NCT05549856. Registered on September 22, 2022.

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is a widely used modality for acquiring various target samples, but its efficacy in gallbladder masses is unknown. The aim of this retrospective study was to evaluate the efficacy and safety of EUS-FNB in patients with gallbladder masses.

The study samples were composed of patients from March 2015 to July 2019 who needed to identify the nature of gallbladder masses through EUS-FNB. The outcomes of this study were the adequacy of specimens, diagnostic yields, technical feasibility, and adverse events of the EUS-FNB in gallbladder masses.

A total of 27 consecutive patients with a median age of 58 years were included in this study. The 22-gauge FNB needle was feasible in all lesions. The median follow-up period of the patients was 294 days. The specimens sufficient for diagnosis account for 89% (24/27) and 93% (25/27) in cytology and histology, respectively. The overall diagnostic yields for malignancy showed the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 95.45% [95% confidence interval (CI): 75.12%-99.76%], 100% (95% CI: 46.29%-100%), 100% (95% CI: 80.76%-100%), 83.33% (95% CI: 36.48%-99.12%), and 96.30% (95% CI: 80.20%-99.99%), respectively. The subgroup analysis revealed that FNB could obtain sufficient specimens and high diagnostic yields in both gallbladder mass < 20.5 mm group and ≥ 20.5 mm group. One patient experienced mild abdominal pain after the procedure and recovered within one day.

EUS-FNB is a reasonable diagnostic tool for the pretreatment diagnosis of patients with gallbladder masses, especially for patients who may miss the opportunity of surgery and need sufficient specimens to identify the pathological type so as to determine chemotherapy regimens. Further large-scale studies are needed to confirm our conclusion.

Evidence comparing ultrasound endoscopy-guided fine-needle biopsy (EUS-FNB) with EUS-guided fine-needle aspiration (EUS-FNA) in deep-seated lymphoma tissue sampling is insufficient. This study aims to evaluate the diagnostic efficacy of immunohistochemistry (IHC) or flow cytometry (FCM) on specimens obtained from EUS-FNB and EUS-FNA in the diagnosis and staging of deep-seated lymphomas. This real-world, dual-center study prospectively evaluated all eligible specimens from patients who underwent EUS-FNB/FNA over an 8-year period. 53 patients were enrolled, with 23 patients in the EUS-FNB group and 30 patients in the EUS-FNA group. FNB yielded specimens with longer core tissues (0.80 mm [0.55, 1.00] vs. 0.45 mm [0.30, 0.50], p = 0.009) and higher scores of specimen adequacy [4 (3.75, 4.00) vs. 3 (1.00, 4.00), p = 0.025]. Overall analysis revealed that the diagnostic accuracy of IHC based on specimens acquired from EUS-FNB was significantly higher than that of EUS-FNA (91.30% vs. 60.00%, p = 0.013). After controlling confounding factors including lesion size and endoscopists, EUS-FNB with IHC maintained a higher-level diagnostic accuracy compared to EUS-FNA (OR = 1.292 [1.037-1.609], p = 0.023). When FCM was additionally used to analyze the specimen acquired from EUS-FNA, the diagnostic yield was significantly improved (ROC AUC: 0.733 vs. 0.550, p = 0.015), and the AUC of FNB alone or combined with FCM was 0.739 and 0.761. Conclusions: FNB needles generate higher histopathological diagnostic accuracy and specimen quality than FNA for the deep-seated lymphoma. Though the application of FCM significantly improves the diagnostic efficacy of EUS-FNA, FNB was still the preferred diagnostic modality with a shorter procedure time, comparable diagnostic accuracy, and better cost-effectiveness.

Background and study aims Despite the widespread use of endoscopic ultrasound (EUS)-guided tissue acquisition, the choice of optimal suction technique remains a subject of debate. Multiple studies have shown conflicting results with respect to the four suction techniques: Dry suction (DS), no suction (NS), stylet slow-pull (SSP) and wet suction (WS). Thus, the present network meta-analysis (NMA) was conducted to compare the diagnostic yields of above suction techniques during EUS-guided tissue acquisition. Methods A comprehensive literature search from 2010 to March 2022 was done for randomized trials comparing the aspirated sample and diagnostic outcome with various suction techniques. Both pairwise and network meta-analyses were performed to analyze the outcomes: sample adequacy, moderate to high cellularity, gross bloodiness and diagnostic accuracy. Results A total of 16 studies (n=2048 patients) were included in the final NMA. WS was associated with a lower odd of gross bloodiness compared to DS (odds ratio 0.50, 95% confidence interval 0.24-0.97). There was no significant difference between the various suction methods with respect to sample adequacy, moderate to high cellularity and diagnostic accuracy. On meta-regression, to adjust for the effect of needle type, WS was comparable to DS in terms of bloodiness when adjusted for fine-needle aspiration needle. Surface under the cumulative ranking analysis ranked WS as the best modality for all the outcomes. Conclusions The present NMA did not show superiority of any specific suction technique for EUS-guided tissue sampling with regard to sample quality or diagnostic accuracy, with low confidence in estimates.

In endoscopic ultrasound (EUS)-fine-needle biopsy (FNB) of solid pancreatic mass lesions, the number of times the needle moves back and forth within the lesion might affect the collection of the sample and the subsequent diagnostic accuracy. Thus, this study was designed to compare the diagnostic adequacy between different numbers of back-and-forth movements in EUS-FNB.

Fifty-five patients with solid pancreatic masses underwent EUS-FNB sampling with the needle (22-gauge) moved 20 times (MTT) and 40 times (MFT) randomly and sequentially for a total of four alternating passes. We compared the acquisition rate of appropriate and adequate specimens for histologic assessment and diagnostic accuracy.

Finally, 55 patients (35 men and 20 women) were included in the study. We found that 56.4% (31/55) and 60% (33/55) of the specimens obtained using MTT and MFT, respectively, could be adequately diagnosed histologically (P = 0.815, McNemar test). The diagnostic accuracy of MTT and MFT was 72.7% (40/55) and 80% (44/55), respectively (P = 0.289, McNemar test). The overall diagnostic accuracy was 89.1%.

There was no significant statistical difference between the histopathological diagnostic samples obtained in MTT and those obtained in MFT. Therefore, a large number of back-and-forth movements of the needle should be avoided during EUS-FNB, which can help reduce the operation time and may reduce the risk of intraoperative and postoperative complications (Clinical trial registration number: ChiCTR2000031106).

Mediastinal lesions are diagnosed sometimes by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). Wet-heparinized suction technique has been used to improve the quality of abdominal solid tumor samples obtained by EUS-FNA. The aim of the study is to assess the effect of wet-heparinized suction on the quality of mediastinal solid tumor samples and to evaluate the safety of the method.

The medical records, EUS-FNA records, pathologic data, and follow-up data between the patients who suspected mediastinal lesions with wet-heparinized suction and conventional suction were retrospectively and comparatively analyzed. Adverse events at 48 h and 1 week after EUS-FNA were evaluated.

Wet-heparinized suction contributed to more tissue specimens (P < 0.05), superior tissue integrity (P < 0.05), and a longer length of white tissue core (P < 0.05). In addition, the more complete the tissue bar was, the higher the rate of successful sample (P < 0.05). Moreover, the total length of the white tissue bar at the first puncture was remarkably longer in the Experimental group (P < 0.05). No significant difference in red blood cell contamination in paraffin sections was found between the two groups (P > 0.05). There was no complication after discharge in both groups.

Wet-heparinized suction can improve the quality of mediastinal lesion samples obtained by EUS-FNA and increase the success rate of sampling. In addition, it will not aggravate blood contamination in paraffin sections while ensuring a safe puncture.

To comprehensively compare the wet suction technique with the conventional dry suction technique for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in solid lesions.

Optimal suction techniques for EUS-FNA remain uncertain when approaching solid lesions.

We performed a retrospective study of EUS-FNA at 3 medical centers in China. A total of 203 patients were enrolled who received 2 passes of EUS-FNA with 22-G needles. If the first pass underwent dry suction, the second pass was wet suction. Otherwise, the order of suction technique is opposite. Diagnostic accuracy, sample quality (including cellularity and blood contamination), and sample quantity (including specimen adequacy, the maximum intact specimen length, and the total specimen length) were compared between wet-suction and dry-suction techniques.

The patients included 143 pancreatic lesions and 60 nonpancreatic lesions. Compared with the dry suction technique, the wet suction technique yielded a significantly higher diagnostic accuracy (85.22% vs. 72.41%, P =0.002), better specimen adequacy score and cellularity score ( P <0.0001), and lower blood contamination score ( P <0.0001). In the subgroup analysis, wet suction provided significantly higher diagnostic accuracy in pancreatic cancer without chronic pancreatitis ( P <0.05), and better cellularity score and specimen adequacy score, lower blood contamination score, and longer maximum intact specimen length and total specimen length in various lesions than that in dry suction.

The wet suction technique resulted in significantly higher diagnostic accuracy in pancreatic cancer without chronic pancreatitis, and better cellularity and histologic specimen in most of solid lesions.

A high-quality sample allows for next-generation sequencing and the administration of more tailored precision medicine treatments. We aimed to evaluate whether heparinized wet suction can obtain higher quality samples than the standard dry-suction method during endoscopic ultrasound (EUS)-guided biopsy of pancreatic masses.

A prospective randomized crossover study was conducted. Patients with a solid pancreatic mass were randomly allocated to receive either heparinized wet suction first or dry suction first. For each method, two needle passes were made, followed by a switch to the other method for a total of four needle punctures. The primary outcome was the aggregated white tissue length. Histological blood contamination, diagnostic performance and adverse events were analyzed as secondary outcomes. In addition, the correlation between white tissue length and the extracted DNA amount was analyzed.

A total of 50 patients were enrolled, and 200 specimens were acquired (100 with heparinized wet suction and 100 with dry suction), with one minor bleeding event. The heparinized wet suction approach yielded specimens with longer aggregated white tissue length (11.07 mm vs 7.96 mm, p=0.001) and less blood contamination (p=0.008). A trend towards decreasing tissue quality was observed for the 2nd pass of the dry-suction method, leading to decreased diagnostic sensitivity and accuracy, although the accumulated diagnostic performance was comparable between the two suction methods. The amount of extracted DNA correlated positively to the white tissue length (p=0.001, Spearman̕s ρ=0.568).

Heparinized wet suction for EUS tissue acquisition of solid pancreatic masses can yield longer, bloodless, DNA-rich tissue without increasing the incidence of adverse events (ClinicalTrials.gov. identifier NCT04707560).

BACKGROUND : It is unknown whether there is an advantage to using the wet-suction or slow-pull technique during endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) with new-generation needles. We aimed to compare the performance of each technique in EUS-FNB.

This was a multicenter, randomized, single-blind, crossover trial including patients with solid lesions of ≥ 1 cm. Four needle passes with 22 G fork-tip or Franseen-type needles were performed, alternating the wet-suction and slow-pull techniques in a randomized order. The primary outcome was the histological yield (samples containing an intact piece of tissue of at least 550 μm). Secondary end points were sample quality (tissue integrity and blood contamination), diagnostic accuracy, and adequate tumor fraction.

Overall, 210 patients with 146 pancreatic and 64 nonpancreatic lesions were analyzed. A tissue core was retrieved in 150 (71.4 %) and 129 (61.4 %) cases using the wet-suction and the slow-pull techniques, respectively (P = 0.03). The mean tissue integrity score was higher using wet suction (P = 0.02), as was the blood contamination of samples (P < 0.001). In the two subgroups of pancreatic and nonpancreatic lesions, tissue core rate and tissue integrity score were not statistically different using the two techniques, but blood contamination was higher with wet suction. Diagnostic accuracy and tumor fraction did not differ between the two techniques.

Overall, the wet-suction technique in EUS-FNB resulted in a higher tissue core procurement rate compared with the slow-pull method. Diagnostic accuracy and the rate of samples with adequate tumor fraction were similar between the two techniques.

Suction pressure is one of the most important factors influencing the amount of tissue obtained during endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/FNB). In this study we aimed to elucidate actual suction pressure generated by various suction methods and the weight of suctioning liquid.

Different types of fine needles and suction techniques were used, including the slow pull technique (SPT), dry suction technique (DST), wet suction technique (WST), neutralizing negative pressure technique (NNPT), and residual negative pressure technique (RNPT). Actual suction pressure was measured and the amount of suctioning liquid was weighed.

Actual suction pressure and weight of the suctioning liquid were lower using SPT than using DST, while they were higher when using WST compared with those using DST. In general, the actual suction pressure increased and the weight of suctioning liquid decreased as the diameter of the FNA needles decreased. While weight of the suctioning liquid using FNB needles was significantly larger than that using FNA needles. In general, the actual suction pressure generated using RNPT was larger than that using NNPT.

WST is superior to SPT and DST in terms of actual suction pressure and weight of suctioning liquid. Diameter of the FNA needle was an important factor that may affect the actual suction pressure and weight of suctioning liquid. FNB needles are superior to FNA needles when it comes to the weight of suctioning liquid. Actual suction pressure obtained by novel suction methods (NNPT and RNPT) may provide a basis for future research.

It remains unclear whether the use of the stylet slow-pull (SP) and wet suction (WS) can improve the yield of endoscopic ultrasound-guided fine-needle biopsy compared to standard suction (SS). The aim of this study was to compare the diagnostic efficacy of the three sampling techniques when using 25G ProCore needles for solid pancreatic lesions.

This multicenter single-blind randomized crossover superiority trial enrolled patients with solid pancreatic lesions (n = 300) from four digestive endoscopic centers in China. All three sampling techniques were performed on each patient using a 25G ProCore needle in a randomized sequence. The diagnostic efficacy, the specimen yield, and quality of each technique, the overall technical success rate and diagnostic yield of the 25G ProCore needle, and rate of adverse events were evaluated.

A total of 291 patients were analyzed. No significant difference was found in diagnostic efficiency among the three techniques (sensitivity, 82.14% vs. 75.00% vs. 77.86, P = 0.1186; accuracy, 82.82% vs. 75.95% vs. 78.69%, P = 0.1212). The SP had an inferior tissue integrity compared to the SS and WS techniques (71.82% vs. 62.55% vs. 69.76%, P = 0.0096). There was no significant difference in the degree of blood contamination among the three groups (P = 0.2079). After three passes, the overall sensitivity was 93.93%, and the accuracy was 94.16%.

SS and WS techniques are better choices than SP technique for 25G ProCore needle, for they could provide higher specimen adequacy without increasing the amount of blood contamination. The 25G ProCore needle can provide a satisfactory diagnostic yield for solid pancreatic lesions.

Data on adequacy of EUS guided biopsies using different tissue acquisition techniques and fine needle aspiration needle designs have been inconclusive. Data on newer fine needle biopsy (FNB) needles are scarce. This study compared the performance of 3 acquisition techniques and 2 fine needle biopsy designs in solid pancreatic lesions.

Single-center, randomized, pilot clinical trial (Trial registration number NCT03264092). Patients undergoing EUS biopsy of pancreatic lesions were randomized to 1 of 3 acquisition techniques (dry suction, wet suction, slow pull) and 1 of 2 22G FNB needle designs. The primary outcome was specimen cellularity. Secondary outcomes included blood contamination and number of passes needed for diagnosis.

A total of 52 (35.3%), 49 (33.3%) and 46 (31.3%) specimens were obtained with slow pull, dry suction and wet suction, respectively. A total of 56 (38%) and 91 (62%) specimens were obtained with each needle, respectively. No difference in cellularity scores was identified by technique (3.28 vs 3.55 vs 2.94; p = 0.081) or needle type (3.45 vs 3.15; p = 0.19). The same was true for blood contamination and diagnostic pass. A diagnosis was reached after 3 passes in 51 patients (93%). Histological diagnosis was possible in 45 specimens (82%). No severe adverse events occurred.

Cellularity of pancreatic specimens obtained with FNB needles via EUS was not influenced by technique and needle design. Three passes were enough to obtain a histological diagnosis in most patients. Larger clinical trials are required to validate the results of this study.

Background and study aims  In this study, we evaluated the performance of community hospitals involved in the Dutch quality in endosonography team regarding yield of endoscopic ultrasound (EUS)-guided tissue acquisition (TA) of solid pancreatic lesions using cumulative sum (CUSUM) learning curves. The aims were to assess trends in quality over time and explore potential benefits of CUSUM as a feedback-tool. Patients and methods  All consecutive EUS-guided TA procedures for solid pancreatic lesions were registered in five community hospitals between 2015 and  2018. CUSUM learning curves were plotted for overall performance and for performance per center. The American Society of Gastrointestinal Endoscopy-defined key performance indicators, rate of adequate sample (RAS), and diagnostic yield of malignancy (DYM) were used for this purpose. Feedback regarding performance was provided on multiple occasions at regional interest group meetings during the study period. Results  A total of 431 EUS-guided TA procedures in 403 patients were included in this study. The overall and per center CUSUM curves for RAS improved over time. CUSUM curves for DYM revealed gradual improvement, reaching the predefined performance target (70 %) overall, and in three of five contributing centers in 2018. Analysis of a sudden downslope development in the CUSUM curve of DYM in one center revealed temporary absence of a senior cytopathologist to have had a temporary negative impact on performance. Conclusions  CUSUM-derived learning curves allow for assessment of best practices by comparison among peers in a multidisciplinary multicenter quality improvement initiative and proved to be a valuable and easy-to-interpret means to evaluate EUS performance over time.

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the main method for acquisition of tissue from gastrointestinal subepithelial lesions (SELs). Despite the development of new needles, diagnostic yield remains low. A new method of aspiration has been described, where the needle is filled with saline [wet-suction technique (WST)], with promising results in pancreatic lesions. This method has not been tested in SELs.

Prospective single center study to assess the diagnostic yield of EUS-FNA+WST in the diagnosis of SELs, without the use of rapid on-site evaluation. In mesenchymal tumors, the diagnosis was considered positive only when immunohistochemistry could differentiate between gastrointestinal stromal tumor and leiomyoma.

Eighty-seven patients with SELs were included (55% male, mean age 66 years). Mean SEL size was 25 mm (min 10 mm, max 120 mm), mean number of passes was 3 (±0.8). A 22G needle was used in 72 patients (83%), 19G in 10 (12%) and 25G in 5 (6%). We obtained a conclusive cytopathological diagnosis in 74 cases (diagnostic yield of 85%) and immunohistochemistry was performed in 70 cases (81%). The most frequent diagnoses were gastrointestinal stromal tumor (n = 34, 37%), leiomyoma (n = 13, 15%) and metastases (n = 10, 11%).

Wet suction technique allowed an excellent diagnostic yield in the EUS-guided evaluation of SELs. We suggest that, after proper replication of these results, WST may become the first-line method in the management of these lesions.

The optimal sampling techniques for EUS-FNA remain unclear and have not been standardized. To improve diagnostic accuracy, suction techniques for EUS-FNA have been developed and are widely used among endoscopists. The aim of this study was to compare wet-suction and dry-suction EUS-FNA techniques for sampling solid lesions. We performed a comprehensive literature search of major databases (from inception to June 2020) to identify prospective studies comparing wet-suction EUS-FNA and dry-suction EUS-FNA. Specimen adequacy, sample contamination, and histologic accuracy were assessed by pooling data using a random-effects model expressed in terms of odds ratio (OR) and 95% confidence interval (CI). Six studies including a total of 418 patients (365 wet suction vs. 377 dry suction) were included in our final analysis. The study included a total of 535 lesions (332 pancreatic lesions and 203 nonpancreatic lesions). The pooled odds of sample adequacy was 3.18 (CI: 1.82-5.54, P = 0.001) comparing wet- and dry-suction cohorts. The pooled odds of blood contamination was 1.18 (CI: 0.75-1.86, P = 0.1). The pooled rate for blood contamination was 58.33% (CI: 53.65%-62.90%) in the wet-suction cohort and 54.60% (CI 49.90%- 59.24%) in the dry-suction cohort (P = 0.256). The pooled odds of histological diagnosis was 3.68 (CI 0.82-16.42, P = 0.1). Very few adverse events were observed and did not have an impact on patient outcomes using either method. EUS-FNA using the wet-suction technique offers higher specimen quality through comparable rates of blood contamination and histological accuracy compared to dry-suction EUS-FNA.

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).

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.

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).

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.

Background and purpose of the study: endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) is the method of choice for sampling pancreatic solid lesions. However, there is significant heterogeneity in terms of the technique used. Intermittent aspiration has not been evaluated in pancreatic solid lesions and could improve the diagnostic performance.

Single-blind, non-inferiority pilot study. Patients with solid pancreatic lesions and indication for EUS-FNA were prospectively included. Patients were randomly assigned to intermittent (IS) or continuous (CS) suction techniques. Diagnostic performance, cellularity, blood contamination and number of passes required to reach diagnosis were evaluated.

33 patients were assigned to CS (16 patients) or IS (17 patients). Diagnostic performance was 87.5% for CS and 94.1% for IS (OR 2.29, 95%CI 0.19-27.99, p = 0.51). In the IS group samples had higher cellularity (OR 1.83, 95%CI 0.48-6.91, p = 0.37) and lower blood contamination (OR 0.38, 95%CI 0.09-1.54, p = 0.18). The number of passes required to reach diagnosis was 2.12 for CS and 1.94 for IS (p = 0.64). Liquid cytology was obtained in 73.3% of IS and 61.5% of CS (OR 1.72, 95%CI 0.35-8.50).

The IS technique was not inferior to CS in terms of diagnostic accuracy in the evaluation of pancreatic solid lesions, with a tendency to obtain higher cellularity, lower blood contamination and frequent presence of cell block.

Endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) is important for the differential diagnosis of solid pancreatic lesions. Sample adequacy is related to the number of needle passes, and European guidelines recommend three to four needle passes with a standard EUS-FNA needle. We aimed to evaluate the optimal number of passes with standard EUS-FNA needles in solid pancreatic lesions.

Patients with solid pancreatic masses without cystic component >20% on computed tomography scan, and without biliary metallic stents, or coagulation problems were included prospectively. Standard 22G needles were used (maximum four passes); each sample was paraffin-embedded and analyzed separately. Final diagnosis was established by EUS-FNA, repeat EUS-FNA, surgery, or follow-up.

Sixty-one of 65 patients were included. The final diagnoses were adenocarcinoma (n = 44, 72%), neuroendocrine tumor (NET) (n = 10, 16%), metastasis (n = 1, 4%) and nonmalignant lesion (n = 6, 10%). Immunohistochemical staining was possible in 17 cases. The diagnosis was established by the first pass in 62% of cases (n = 38), by the second in 15% (n = 9), by the third in 15% (n = 9), and by the fourth in 3% (n = 2). The diagnostic accuracy for all four passes compared to the first three passes was 95% vs 92% (P = .5). The contribution of the fourth pass was not different between adenocarcinoma and NET (2% vs 10%, respectively; P = .667).

Three passes with standard EUS-FNA was optimal for a specific diagnosis of solid pancreatic masses, regardless of the histological type of the lesion.

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.