Comparison of 19-gauge aspiration needles with 20-gauge forward-bevel needles for the diagnosis of autoimmune pancreatitis: a prospective randomized, controlled study

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Here we compared the diagnostic performance and sample adequacy of 19-gauge endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) needles with 20-gauge endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) needles in patients with suspected AIP. Methods Patients with suspected AIP were enrolled between October 2018 and August 2020 into a single-center, prospective, randomized controlled study conducted at a tertiary medical center in Beijing. Participants were randomly assigned to undergo tissue specimen collection using either a 19-gauge EUS-FNA needle or a 20-gauge EUS-FNB needle. The primary endpoint was the sensitivity of the two needle types for diagnosing AIP, with secondary endpoints including diagnostic sufficiency of tissue obtained, technical success rate, adverse event rate, and contribution of histologic findings to the AIP diagnosis according to International Consensus Diagnostic Criteria. Results Forty-five patients were enrolled. There was no significant difference in diagnostic efficacy between the 19-gauge FNA needle and the 20-gauge forward-beveled FNB needle for AIP. Both needle types showed similar sensitivity and overall accuracy in diagnosing benign disease, including AIP. The median tissue length was comparable between the two groups, and there was no significant difference in adverse events. Conclusions There is no difference in diagnostic efficacy or core tissue acquisition between 19-gauge FNA and 20-gauge forward-beveled FNB needles for patients with AIP. The 19-gauge FNA needle may serve as an alternative in centers where FNB needles are not available. Trial Registration ClinicalTrials.gov NCT03753815 Autoimmune pancreatitis EUS-FNA EUS-FNB needle diagnostic performance prospective randomized controlled trial Figures Figure 1 Figure 2 BACKGROUND Autoimmune pancreatitis (AIP) is a distinct form of chronic pancreatitis with an autoimmune pathoetiology [ 1 ]. According to International Consensus Diagnostic Criteria (ICDC), diagnosing AIP requires a multidisciplinary approach that includes serology, histopathology, imaging, establishment of other organ involvement, and response to steroid therapy [ 2 ]. The histopathological diagnosis plays an important role in ruling out malignancy, especially for focal AIP with mass formation and type 2 AIP [ 3 ]. Type 1 AIP, or lymphoplasmacytic sclerosing pancreatitis (LPSP), is characterized by histological features of periductal lymphoplasmatic infiltrates, obliterative phlebitis, storiform fibrosis, and increased IgG4-positive cell infiltrates [ 4 ]. Type 2 AIP is characterized by granulocytic epithelial lesions (GELs) with or without granulocytic acinar inflammation [ 5 ]. Endoscopic ultrasound (EUS) guides tissue acquisition through fine needle aspiration (FNA) and fine needle biopsy (FNB) [ 6 ]. However, EUS-FNA is not included in the guidelines as a method for establishing a pathological diagnosis of AIP due to a lack of evidence regarding obtaining adequately-sized specimens for FNA evaluation [ 7 ]. Nevertheless, previous studies have reported a diagnostic sensitivity of 43–60% using EUS-FNA for AIP, making it a valid diagnostic tool [ 8 – 11 ]. Several studies have also evaluated EUS-FNB in AIP, with promising results [ 12 – 15 ], but there are little data comparing the diagnostic performance of EUS-FNA and EUS-FNB for AIP. We therefore prospectively compared the diagnostic performance and sample size adequacy of 19-gauge EUS-FNA needles (EchoTip, Cook Medical or Expect, Boston Scientific Corporation) and 20-gauge EUS-FNB needles (ProCore, Cook Medical) in patients with AIP. METHODS Patients Consecutive patients with suspected of AIP were prospectively enrolled from October 2018 to August 2020. Inclusion criteria were suspected AIP, informed consent provided, and no other serious or uncontrolled medical illness. Exclusion criteria were patient age less than 18 years, uncorrectable coagulopathy (INR > 1.5) or uncorrectable thrombocytopenia (platelet count < 50,000), lesions inaccessible to EUS, and refusal to participate. Study design This single-center, prospective, randomized controlled study was conducted at a tertiary medical center in Beijing (Fig. 1 ). The Peking Union Medical College Hospital Human Ethics Committee approved the study, which is registered on ClinicalTrials.gov (NCT03753815). Randomization Computer-generated randomization assignments were obtained prior to study enrollment using the block randomization method. Eligible patients were randomly assigned to either the 19G group (19-gauge EchoTip needle or 19-gauge Expect needle) or the 20G group (20-gauge ProCore needle) with a 1:1 allocation. Procedures All EUS-FNA or EUS-FNB examinations were performed by endoscopists who had performed more than 200 EUS-FNA or EUS-FNB cases. The same EUS techniques were used in both groups, which were no suction and fanning the needle > 15 times to-and-fro within the lesion. Two passes were performed in each patient. Samples were expelled into formalin bottles with the stylet and processed for histological analysis. Pathological evaluation Tissue fragments were fixed in 10% neutral-buffered formalin and processed for histopathological evaluation. Sections were cut and stained with hematoxylin and eosin, elastic van Gieson, and IgG4. A pathologist (X.C.) blinded to the type of needle used and the clinical information assessed all samples for (1) length of pancreatic tissue obtained, (2) lymphoplasmacytic infiltration, (3) IgG4-positive plasma cell infiltration, (4) presence of storiform fibrosis and obliterative phlebitis, and (5) histologic diagnosis of AIP using the ICDC. A tissue sample with length at least 500 µm was considered adequate. IgG4-positive plasma cell infiltration was defined as the presence of > 10 IgG4-positive plasma cells per high power field (HPF). Level 1 or level 2 diagnostic criteria for type 1 AIP were defined as the concomitant presence of any three or two of the four key histopathologic features of LPSP: (1) lymphoplasmacytic infiltrate, (2) storiform fibrosis, (3) obliterative phlebitis, and (4) > 10 IgG4-positive cells per HPF. Level 1 diagnostic criteria for type 2 AIP were a granulocytic epithelial lesion (GEL) with or without granulocytic acinar inflammation, whereas level 2 diagnostic criteria were a granulocytic and lymphoplasmacytic acinar infiltrate. Study outcomes The primary endpoint was sensitivity of the two needle types for the diagnosis of AIP. The secondary endpoints were: (1) diagnostic sufficiency of tissue obtained by the needles; (2) technical success rate of the needles; (3) the rate of adverse events related to the needles; and (4) the level of contribution of histological findings to the diagnosis of AIP according to the ICDC. Sample size calculation The primary analysis was the comparison between an EUS-FNB needle and an EUS-FNA needle for the histological diagnosis of AIP. The assumed sensitivity for histological diagnosis of AIP by FNA was 60% and the assumed sensitivity for histological diagnosis of AIP by FNB was 80% according to the previous reports [ 13 ]. To achieve a statistical power of 80% with the assumption of a two-sided type I error rate of 2.5%, a total of 20 per group was calculated. Assuming a 15% drop-out rate, we calculated the final sample size of 46 patients (23 per group). Statistical analysis and data management Categorical parameters were compared by chi-squared and Fisher’s exact tests, and continuous variables were compared with Student’s t -test and presented as percentages with 95% confidence intervals (CI). Analyses were performed using SPSS v23.0 (SPSS, Chicago, IL, USA), with results considered significant at a P-value < 0.05. RESULTS Patients Forty-five patients with suspected AIP were enrolled in the study (Fig. 1 ). Baseline characteristics did not differ significantly between groups (Table 1 ). The quantity of tissue obtained was analyzed in all 45 patients; three patients were excluded from evaluation of the pathologic diagnosis of AIP because the final diagnosis was not AIP. Table 1 Comparison of patient characteristics by group. FNB group (n = 23) FNA group (n = 22) P-value Male sex, n (%) 21(91.3) 17(77.3) 0.243 Median age, y (range) 55(29–82) 61(28–77) 0.879 Jaundice, n (%) 11(47.8) 12(54.5) 0.768 Pancreatic enlargement 0.307 Diffuse, n (%) 14(60.9) 17(77.3) Segmental, n (%) 2(8.7) 1(4.5) Focal, n (%) 7(30.4) 4(18.2) Serum IgG4 Median levels, mg/dl, (ragne) 757(4.4–3450) 429(56.7–5950) 0.922 IgG4 level < 135, n (%) 3(13.0) 2(9.1) 1.000 Puncture site 0.585 Pancreatic head 12(52.2) 8(36.4) Pancreatic body 10(43.5) 14(63.6) Pancreatic tail 1(4.3) 0 Final diagnosis Type 1 AIP 21 19 Type 2 AIP 2 Non-specified diagnosis 2 1 Abbreviations: FNB, fine-needle biopsy; FNA, fine-needle aspiration; AIP, autoimmune pancreatitis Tissue specimen quantity and pathological evaluation EUS was successfully performed in 45 patients. No core tissue specimen was obtained in eight patients (34.8%) in the FNB group and in seven patients (31.8%) in the FNA group (P = 0.833) (Table 2 ). For diagnosing benign diseases including AIP, the FNA group and FNB group had similar sensitivity (47.6% vs 47.6%) and overall accuracy (50% vs 52.2%). Table 2 Study outcomes of EUS-FNA or EUS-FNB in patients with AIP. FNB group (n = 23) FNA group (n = 22) OR 95% confidence interval P-value Technical success, n (%) 23 (100) 22 (100) Tissue cores acquired, n (%) 15 (65.2) 15 (68.2) 0.875 0.253 ~ 3.028 0.833 Length > 3 mm 9(39.1) 4(18.2) 5.063 0.957 ~ 26.78 0.005 Median length, mm (range) 3 (0.5 ~ 8.3) 1.5 (0.5 ~ 11) 0.606 Level 1 and level 2, n (%) 10 (43.5) 10 (45.5) 1.083 0.334 ~ 3.513 1.000 Level 1, n (%) 6 (26.1) 3 (13.7) 0.447 0.097 ~ 2.071 0.459 Level 2, n (%) 4 (17.4) 7 (31.8) 2.217 0.545 ~ 9.013 0.314 Impossibility of diagnosis, n 6 7 Overall adverse events, n (%) 1 (4.3) 1 (4.5) 1.048 0.061 ~ 17.852 1.000 Mild pancreatitis, n - 1 Mild bleeding, n 1 - Abbreviation: OR, odds ratio With respect to the histopathological diagnosis of AIP, tissue lengths were compared between two groups. The median length of tissue was 3 mm in the FNB group and 1.5 mm in the FNA group (P = 0.606). Level 1 or 2 AIP histology was diagnosed in ten patients (43.5%) in the FNB group and in ten patients (45.5%) in the FNA group (P = 1.000), with level 1 histology diagnosed in 26.1% and 13.7% of patients in the FNB and FNA groups, respectively (P = 0.459). There was only one procedure-related adverse event in each group: mild pancreatitis and mild bleeding (P = 1.000). Of the 45 patients with a final diagnosis of AIP, 23 patients were definitively diagnosed with type 1 AIP without the need for histological findings based on other ICDC criteria. The remaining 22 patients could not be definitively diagnosed with AIP without histology, with four patients having level 1 histological findings and six patients level 2 histologic findings (Table 3 ). The remaining 12 patients with no confirmed histologic diagnosis by EUS were diagnosed after a steroid trial. Table 3 Contribution of histological findings to the diagnosis of AIP according to the ICDC. Definitive AIP by ICDC without histology of the pancreas Not definitive AIP by ICDC without histology of the pancreas Histologic diagnosis Level 1 Level 2 Not diagnosed FNB group (N = 23), n 10 4 3 6 FNA group (N = 22), n 13 0 3 6 Total (N = 45), n 23 4 6 12 Note: P = 0.415 DISCUSSION Histologic evaluation is an important component of the diagnosis of AIP. Previous studies describing sample acquisition from AIP have reported that FNB is associated with a higher diagnostic sensitivity and sample adequacy than FNA [ 16 – 18 ]. However, these were retrospective studies that lacked protocolled management algorithms. To our best knowledge, the present study is the first prospective comparison of EUS-FNB and EUS-FNA needles in AIP patients. For patients with AIP, there was no difference in diagnostic efficacy between the 19G FNA needle and the 20G forward-beveled FNB needle. FNA, though less than satisfactory, was the approach of choice for the diagnosis of AIP in the “pre-FNB” era, even though only 15–60% patients had a definite histological diagnosis (level 1 or 2 according to ICDC) with the use of 22-gauge FNA needles [ 8 , 10 , 11 , 19 , 20 ]. Although there is a lack of RCTs comparing the diagnostic efficacy of differently-sized FNA needles for AIP, many endoscopists believe that thicker needles obtain more tissue, driving a preference for using 19-gauge FNA needles for AIP. This was also the choice of most endoscopists at our center before FNB needles became available. In our study, 19-gauge FNA needle resulted in 45.5% level 1 and 2 histological diagnosis of AIP, consistent with previous studies [ 9 ]. The advent of FNB needles improved the efficacy for diagnosing AIP [ 16 , 17 ]. FNB needles commonly used in current clinical practice include side-fenestrated forward-cutting beveled needles, reverse beveled needles, Franseen-tip needles, and fork-tip needles (Fig. 2 ). The FNB needle used in our study was the 20G side-fenestrated forward-cutting beveled needle (ProCore™), which contains a Menghini type tip and a straight bevel located on the proximal side of the lateral window, allowing the core trap to catch more tissue while the needle moves forward [ 21 ]. This needle is now widely used by endoscopists worldwide. Compared with the earlier 22G reverse-beveled needle (ProCore™), the 20G needle offers better maneuverability and greater tissue acquisition [ 22 ]. Indeed, the histological accuracy of the 20G FNB needle has been reported to be as high as 96.4% in pancreatic carcinoma patients [ 23 ]. For AIP, ~ 45% of patients with highly-suggestive features of AIP were diagnosed with level 1 or 2 histological findings via the 20G forward-bevel FNB needle [ 13 ]. Some of the histological features of AIP like storiform fibrosis and obliterative phlebitis need more core tissue for their confirmation. Although we found that the proportion of cases with > 3 mm tissue acquisition with the 20G FNB needle was higher than that obtained with the 19G FNA needle, there was no difference in the proportion of level 1 or 2 diagnoses between the two groups, suggesting that obtaining tissue > 3 mm might not be necessary to confirm the diagnosis of AIP. It is worth mentioning that Franseen and Forktip FNB needles both have good diagnostic performance for AIP. The 22G Franseen needle was reported to result in a higher proportion (78%) of level 1 or 2 histological findings compared with 20G forward-bevel FNB needles (45%) in AIP patients [ 13 ]. The Asian EUS Group (AEG) recently developed guidelines regarding EUS-guided tissue acquisition [ 24 ], which recommend the use of Franseen or fork-tip FNB needles in preference to side-bevel FNB needles, where feasible, when histological specimens are required from pancreatic lesions. However, the 22G Franseen and Forktip needles were not available at our center at the time of this study. Our present study suggests that for centers where FNB needles are not available, the 19G FNA needle might be an alternative and achieve similar diagnostic performance to the 20G FNB needle. This study has several limitations. First, most included cases were type 1 AIP and only two cases were diagnosed as type 2 AIP in the FNA group. There are very little published data on EUS-FNA or FNB in diagnosing type 2 AIP due to the rarity of the disease, and most studies have included no more than three cases of type 2 AIP [ 15 , 25 – 28 ], as here. Nevertheless, under the assumption that more tissue acquisition is key to improving the diagnosing of both type 1 and type 2 AIP, our results can reasonably be applied to type 2 AIP. Second, our evaluation was based on tissue acquisition “per patient” instead of “per pass”. However, we punctured every patient twice in this study, minimizing potential over-rating of tissue acquisition. CONCLUSIONS In summary, our study reveals that there is no difference in diagnostic efficacy or core tissue acquisition between the 19G FNA needle and the 20G forward-beveled FNB needle for patients with AIP. We suggest that the 19G FNA needle might be an alternative for centers where FNB needles are not available. Abbreviations AIP: Autoimmune pancreatitis ICDC: International Consensus Diagnostic Criteria LPSP: Lymphoplasmacytic sclerosing pancreatitis GELs: Granulocytic epithelial lesions EUS: Endoscopic ultrasound FNA: Fine needle aspiration FNB: Fine needle biopsy Declarations Ethics approval and consent to participate: The Peking Union Medical College Hospital Human Ethics Committee approved the study (number: ZS-1767). All patients provided written informed consent. Consent for publication: Not applicable. Availability of data and materials: The datasets used and/or analysed during the current study are available from the corresponding authors on reasonable request. Competing interests: Drs. Wen Shi, Xiaoyan Chang, Shengyu Zhang, Tao Guo, Qingwei Jiang, Qiang Wang, Dongsheng Wu, Yanyan Wu, Yunlu Feng, and Aiming Yang have no conflicts of interest or financial ties to disclose. Funding: This work was supported by National High Level Hospital Clinical Research Funding [grant number 2022-PUMCH-B-024, 2022-PUMCH-A-177, 2022-PUMCH-A-076] and National Natural Science Foundation of China [grant number 32370946] Authors’ contributions: Study concept and design and paper preparation: W Shi, XY Chang, and YL Feng. Paper preparation and Statistical analysis: W Shi, YL Feng, SY Zhang, and YY Wu. Paper preparation and critical revisions: AM Yang, T Guo, X Wu, QW Jiang, Q Wang, and DS Wu. References Dong Y, D'Onofrio M, Hocke M, Jenssen C, Potthoff A, Atkinson N, Ignee A, Dietrich CF. Autoimmune pancreatitis: Imaging features. Endosc Ultrasound. 2018;7(3):196-203. 10.4103/eus.eus_23_17 Shimosegawa T, Chari ST, Frulloni L, Kamisawa T, Kawa S, Mino-Kenudson M, Kim MH, Klöppel G, Lerch MM, Löhr M, Notohara K. International consensus diagnostic criteria for autoimmune pancreatitis: guidelines of the International Association of Pancreatology. 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Pathol Int. 2017;67(10):514-520. 10.1111/pin.12563 Matsumoto Y, Shimizu A, Ogawa K, Nakamura M, Hoki S, Kuroki S, Yano Y, Ikuta K, Senda E, Shio S. Late-onset type-2 autoimmune pancreatitis with two mass lesions diagnosed by endoscopic ultrasound-guided fine-needle aspiration. Clin J Gastroenterol. 2021;14(3):899-904. 10.1007/s12328-021-01364-z Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4407496","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":304366263,"identity":"567d28b8-028c-4a4a-b14b-5876295f70be","order_by":0,"name":"Wen Shi","email":"","orcid":"","institution":"Peking Union Medical College Hospital","correspondingAuthor":false,"prefix":"","firstName":"Wen","middleName":"","lastName":"Shi","suffix":""},{"id":304366271,"identity":"0310f6d0-67f2-4f45-9d26-97387e2db4a2","order_by":1,"name":"Xiaoyan Chang","email":"","orcid":"","institution":"Peking Union Medical College Hospital","correspondingAuthor":false,"prefix":"","firstName":"Xiaoyan","middleName":"","lastName":"Chang","suffix":""},{"id":304366272,"identity":"cddb1da3-a694-4f53-a30d-4d30b3573754","order_by":2,"name":"Shengyu Zhang","email":"","orcid":"","institution":"Peking Union Medical College Hospital","correspondingAuthor":false,"prefix":"","firstName":"Shengyu","middleName":"","lastName":"Zhang","suffix":""},{"id":304366273,"identity":"caeef36b-c50a-4e68-8d2d-96f07414e278","order_by":3,"name":"Qingwei Jiang","email":"","orcid":"","institution":"Peking Union Medical College Hospital","correspondingAuthor":false,"prefix":"","firstName":"Qingwei","middleName":"","lastName":"Jiang","suffix":""},{"id":304366274,"identity":"fff70494-b952-4a74-b877-01e09b00fc03","order_by":4,"name":"Tao Guo","email":"","orcid":"","institution":"Peking Union Medical College 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Hospital","correspondingAuthor":false,"prefix":"","firstName":"Xi","middleName":"","lastName":"Wu","suffix":""},{"id":304366278,"identity":"3cb80600-edbb-406d-b383-4d28176a4c04","order_by":8,"name":"Yanyan Wu","email":"","orcid":"","institution":"Peking Union Medical College Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yanyan","middleName":"","lastName":"Wu","suffix":""},{"id":304366279,"identity":"ca2a07aa-96bb-43ae-be3f-aab00982ca90","order_by":9,"name":"Yunlu Feng","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAArklEQVRIiWNgGAWjYHACxgMMNjY8DOxAJg+xeg4wpKXxMDCTqOUwA/FaDG7kHjjMk3Behr+Z+ZjEGwY7Od0GglryEoBabvNIHGZLk5zDkGxsdoCglhyDw7w/bvMYMPOYSfMwHEjcRpQWnoRzpGs5QIIWyTNvDA7OSUgG+SXZco4BEX7hO55j+OBNgp09f3vzwRtvKuzkCGpRQFVgQEA5CMg3EKFoFIyCUTAKRjgAAMYWPI8Jc5cIAAAAAElFTkSuQmCC","orcid":"","institution":"Peking Union Medical College Hospital","correspondingAuthor":true,"prefix":"","firstName":"Yunlu","middleName":"","lastName":"Feng","suffix":""},{"id":304366280,"identity":"8ab81cc8-253f-4335-888a-1c07c8a5f2b0","order_by":10,"name":"Aiming Yang","email":"","orcid":"","institution":"Peking Union Medical College Hospital","correspondingAuthor":false,"prefix":"","firstName":"Aiming","middleName":"","lastName":"Yang","suffix":""}],"badges":[],"createdAt":"2024-05-12 06:53:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4407496/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4407496/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":57307499,"identity":"3a261b72-c3b4-4e43-8713-e14414ce3ad9","added_by":"auto","created_at":"2024-05-29 02:15:15","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":147834,"visible":true,"origin":"","legend":"\u003cp\u003eFlow chart of the study.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-4407496/v1/4c29fe104e224ac908089d4e.png"},{"id":57307500,"identity":"729d3e19-b476-4ceb-936f-d37e0d382d8f","added_by":"auto","created_at":"2024-05-29 02:15:15","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":285825,"visible":true,"origin":"","legend":"\u003cp\u003eFNB needles most commonly used in clinical practice. (A) The “old version” side-fenestrated needles (ProCore\u003csup\u003eTM\u003c/sup\u003e) with a reverse bevel, which are available in 19-gauge, 22-gauge, and 25-gauge sizes. (B) The “new version” side-fenestrated needles (ProCore\u003csup\u003eTM\u003c/sup\u003e) with a forward bevel, which are only sold as 20-gauge needles and was the FNB needle used in this study. (C) The fork-tip needle (SharkCore\u003csup\u003eTM\u003c/sup\u003e) with six distal cutting-edge surfaces. (D) The Franseen-tip needle (Acquire\u003csup\u003eTM\u003c/sup\u003e) with three symmetric point cutting surfaces\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-4407496/v1/9463d9c098025bcc38baa972.png"},{"id":68947796,"identity":"ebed2062-044a-40a3-b317-e33ae2bbeb04","added_by":"auto","created_at":"2024-11-13 21:01:33","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1049181,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4407496/v1/eafaa334-2264-44dc-b1ae-3763a95fcd42.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eComparison of 19-gauge aspiration needles with 20-gauge forward-bevel needles for the diagnosis of autoimmune pancreatitis: a prospective randomized, controlled study\u003c/p\u003e","fulltext":[{"header":"BACKGROUND","content":"\u003cp\u003eAutoimmune pancreatitis (AIP) is a distinct form of chronic pancreatitis with an autoimmune pathoetiology [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. According to International Consensus Diagnostic Criteria (ICDC), diagnosing AIP requires a multidisciplinary approach that includes serology, histopathology, imaging, establishment of other organ involvement, and response to steroid therapy [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe histopathological diagnosis plays an important role in ruling out malignancy, especially for focal AIP with mass formation and type 2 AIP [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Type 1 AIP, or lymphoplasmacytic sclerosing pancreatitis (LPSP), is characterized by histological features of periductal lymphoplasmatic infiltrates, obliterative phlebitis, storiform fibrosis, and increased IgG4-positive cell infiltrates [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Type 2 AIP is characterized by granulocytic epithelial lesions (GELs) with or without granulocytic acinar inflammation [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Endoscopic ultrasound (EUS) guides tissue acquisition through fine needle aspiration (FNA) and fine needle biopsy (FNB) [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. However, EUS-FNA is not included in the guidelines as a method for establishing a pathological diagnosis of AIP due to a lack of evidence regarding obtaining adequately-sized specimens for FNA evaluation [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Nevertheless, previous studies have reported a diagnostic sensitivity of 43\u0026ndash;60% using EUS-FNA for AIP, making it a valid diagnostic tool [\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Several studies have also evaluated EUS-FNB in AIP, with promising results [\u003cspan additionalcitationids=\"CR13 CR14\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], but there are little data comparing the diagnostic performance of EUS-FNA and EUS-FNB for AIP.\u003c/p\u003e \u003cp\u003eWe therefore prospectively compared the diagnostic performance and sample size adequacy of 19-gauge EUS-FNA needles (EchoTip, Cook Medical or Expect, Boston Scientific Corporation) and 20-gauge EUS-FNB needles (ProCore, Cook Medical) in patients with AIP.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients\u003c/h2\u003e \u003cp\u003eConsecutive patients with suspected of AIP were prospectively enrolled from October 2018 to August 2020. Inclusion criteria were suspected AIP, informed consent provided, and no other serious or uncontrolled medical illness. Exclusion criteria were patient age less than 18 years, uncorrectable coagulopathy (INR\u0026thinsp;\u0026gt;\u0026thinsp;1.5) or uncorrectable thrombocytopenia (platelet count\u0026thinsp;\u0026lt;\u0026thinsp;50,000), lesions inaccessible to EUS, and refusal to participate.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eStudy design\u003c/h2\u003e \u003cp\u003eThis single-center, prospective, randomized controlled study was conducted at a tertiary medical center in Beijing (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The Peking Union Medical College Hospital Human Ethics Committee approved the study, which is registered on ClinicalTrials.gov (NCT03753815).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eRandomization\u003c/h2\u003e \u003cp\u003eComputer-generated randomization assignments were obtained prior to study enrollment using the block randomization method. Eligible patients were randomly assigned to either the 19G group (19-gauge EchoTip needle or 19-gauge Expect needle) or the 20G group (20-gauge ProCore needle) with a 1:1 allocation.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eProcedures\u003c/h2\u003e \u003cp\u003eAll EUS-FNA or EUS-FNB examinations were performed by endoscopists who had performed more than 200 EUS-FNA or EUS-FNB cases. The same EUS techniques were used in both groups, which were no suction and fanning the needle\u0026thinsp;\u0026gt;\u0026thinsp;15 times to-and-fro within the lesion. Two passes were performed in each patient. Samples were expelled into formalin bottles with the stylet and processed for histological analysis.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003ePathological evaluation\u003c/h2\u003e \u003cp\u003eTissue fragments were fixed in 10% neutral-buffered formalin and processed for histopathological evaluation. Sections were cut and stained with hematoxylin and eosin, elastic van Gieson, and IgG4. A pathologist (X.C.) blinded to the type of needle used and the clinical information assessed all samples for (1) length of pancreatic tissue obtained, (2) lymphoplasmacytic infiltration, (3) IgG4-positive plasma cell infiltration, (4) presence of storiform fibrosis and obliterative phlebitis, and (5) histologic diagnosis of AIP using the ICDC. A tissue sample with length at least 500 \u0026micro;m was considered adequate. IgG4-positive plasma cell infiltration was defined as the presence of \u0026gt;\u0026thinsp;10 IgG4-positive plasma cells per high power field (HPF). Level 1 or level 2 diagnostic criteria for type 1 AIP were defined as the concomitant presence of any three or two of the four key histopathologic features of LPSP: (1) lymphoplasmacytic infiltrate, (2) storiform fibrosis, (3) obliterative phlebitis, and (4)\u0026thinsp;\u0026gt;\u0026thinsp;10 IgG4-positive cells per HPF. Level 1 diagnostic criteria for type 2 AIP were a granulocytic epithelial lesion (GEL) with or without granulocytic acinar inflammation, whereas level 2 diagnostic criteria were a granulocytic and lymphoplasmacytic acinar infiltrate.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eStudy outcomes\u003c/h2\u003e \u003cp\u003eThe primary endpoint was sensitivity of the two needle types for the diagnosis of AIP. The secondary endpoints were: (1) diagnostic sufficiency of tissue obtained by the needles; (2) technical success rate of the needles; (3) the rate of adverse events related to the needles; and (4) the level of contribution of histological findings to the diagnosis of AIP according to the ICDC.\u003c/p\u003e \u003cdiv id=\"Sec9\" class=\"Section3\"\u003e \u003ch2\u003eSample size calculation\u003c/h2\u003e \u003cp\u003eThe primary analysis was the comparison between an EUS-FNB needle and an EUS-FNA needle for the histological diagnosis of AIP. The assumed sensitivity for histological diagnosis of AIP by FNA was 60% and the assumed sensitivity for histological diagnosis of AIP by FNB was 80% according to the previous reports [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. To achieve a statistical power of 80% with the assumption of a two-sided type I error rate of 2.5%, a total of 20 per group was calculated. Assuming a 15% drop-out rate, we calculated the final sample size of 46 patients (23 per group).\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis and data management\u003c/h2\u003e \u003cp\u003eCategorical parameters were compared by chi-squared and Fisher\u0026rsquo;s exact tests, and continuous variables were compared with Student\u0026rsquo;s \u003cem\u003et\u003c/em\u003e-test and presented as percentages with 95% confidence intervals (CI). Analyses were performed using SPSS v23.0 (SPSS, Chicago, IL, USA), with results considered significant at a P-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003ePatients\u003c/h2\u003e \u003cp\u003eForty-five patients with suspected AIP were enrolled in the study (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Baseline characteristics did not differ significantly between groups (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The quantity of tissue obtained was analyzed in all 45 patients; three patients were excluded from evaluation of the pathologic diagnosis of AIP because the final diagnosis was not AIP.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of patient characteristics by group.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFNB group\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;23)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFNA group\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;22)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale sex, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21(91.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17(77.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.243\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian age, y (range)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e55(29\u0026ndash;82)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e61(28\u0026ndash;77)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.879\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eJaundice, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11(47.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12(54.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.768\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePancreatic enlargement\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.307\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiffuse, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14(60.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17(77.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSegmental, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2(8.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1(4.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFocal, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7(30.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4(18.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum IgG4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian levels, mg/dl, (ragne)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e757(4.4\u0026ndash;3450)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e429(56.7\u0026ndash;5950)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.922\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIgG4 level\u0026thinsp;\u0026lt;\u0026thinsp;135, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3(13.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(9.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePuncture site\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.585\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePancreatic head\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12(52.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8(36.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePancreatic body\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10(43.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14(63.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePancreatic tail\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1(4.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFinal diagnosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType 1 AIP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType 2 AIP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNon-specified diagnosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eAbbreviations: FNB, fine-needle biopsy; FNA, fine-needle aspiration; AIP, autoimmune pancreatitis\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eTissue specimen quantity and pathological evaluation\u003c/h2\u003e \u003cp\u003eEUS was successfully performed in 45 patients. No core tissue specimen was obtained in eight patients (34.8%) in the FNB group and in seven patients (31.8%) in the FNA group (P\u0026thinsp;=\u0026thinsp;0.833) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). For diagnosing benign diseases including AIP, the FNA group and FNB group had similar sensitivity (47.6% vs 47.6%) and overall accuracy (50% vs 52.2%).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eStudy outcomes of EUS-FNA or EUS-FNB in patients with AIP.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFNB group\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;23)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFNA group\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;22)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e95% confidence interval\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTechnical success, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23 (100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22 (100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTissue cores acquired, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15 (65.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15 (68.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.875\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.253\u0026thinsp;~\u0026thinsp;3.028\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.833\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLength\u0026thinsp;\u0026gt;\u0026thinsp;3 mm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9(39.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4(18.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5.063\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.957\u0026thinsp;~\u0026thinsp;26.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.005\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian length, mm (range)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (0.5\u0026thinsp;~\u0026thinsp;8.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.5 (0.5\u0026thinsp;~\u0026thinsp;11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.606\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLevel 1 and level 2, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (43.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10 (45.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.083\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.334\u0026thinsp;~\u0026thinsp;3.513\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLevel 1, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6 (26.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (13.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.447\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.097\u0026thinsp;~\u0026thinsp;2.071\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.459\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLevel 2, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (17.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7 (31.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2.217\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.545\u0026thinsp;~\u0026thinsp;9.013\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.314\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eImpossibility of diagnosis, n\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOverall adverse events, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (4.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (4.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.048\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.061\u0026thinsp;~\u0026thinsp;17.852\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMild pancreatitis, n\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMild bleeding, n\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eAbbreviation: OR, odds ratio\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eWith respect to the histopathological diagnosis of AIP, tissue lengths were compared between two groups. The median length of tissue was 3 mm in the FNB group and 1.5 mm in the FNA group (P\u0026thinsp;=\u0026thinsp;0.606). Level 1 or 2 AIP histology was diagnosed in ten patients (43.5%) in the FNB group and in ten patients (45.5%) in the FNA group (P\u0026thinsp;=\u0026thinsp;1.000), with level 1 histology diagnosed in 26.1% and 13.7% of patients in the FNB and FNA groups, respectively (P\u0026thinsp;=\u0026thinsp;0.459). There was only one procedure-related adverse event in each group: mild pancreatitis and mild bleeding (P\u0026thinsp;=\u0026thinsp;1.000).\u003c/p\u003e \u003cp\u003eOf the 45 patients with a final diagnosis of AIP, 23 patients were definitively diagnosed with type 1 AIP without the need for histological findings based on other ICDC criteria. The remaining 22 patients could not be definitively diagnosed with AIP without histology, with four patients having level 1 histological findings and six patients level 2 histologic findings (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The remaining 12 patients with no confirmed histologic diagnosis by EUS were diagnosed after a steroid trial.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eContribution of histological findings to the diagnosis of AIP according to the ICDC.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDefinitive AIP by ICDC without histology of the pancreas\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eNot definitive AIP by ICDC without histology of the pancreas\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistologic diagnosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLevel 1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eLevel 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNot diagnosed\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFNB group (N\u0026thinsp;=\u0026thinsp;23), n\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFNA group (N\u0026thinsp;=\u0026thinsp;22), n\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal (N\u0026thinsp;=\u0026thinsp;45), n\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNote: P\u0026thinsp;=\u0026thinsp;0.415\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eHistologic evaluation is an important component of the diagnosis of AIP. Previous studies describing sample acquisition from AIP have reported that FNB is associated with a higher diagnostic sensitivity and sample adequacy than FNA [\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. However, these were retrospective studies that lacked protocolled management algorithms. To our best knowledge, the present study is the first prospective comparison of EUS-FNB and EUS-FNA needles in AIP patients.\u003c/p\u003e \u003cp\u003eFor patients with AIP, there was no difference in diagnostic efficacy between the 19G FNA needle and the 20G forward-beveled FNB needle. FNA, though less than satisfactory, was the approach of choice for the diagnosis of AIP in the \u0026ldquo;pre-FNB\u0026rdquo; era, even though only 15\u0026ndash;60% patients had a definite histological diagnosis (level 1 or 2 according to ICDC) with the use of 22-gauge FNA needles [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Although there is a lack of RCTs comparing the diagnostic efficacy of differently-sized FNA needles for AIP, many endoscopists believe that thicker needles obtain more tissue, driving a preference for using 19-gauge FNA needles for AIP. This was also the choice of most endoscopists at our center before FNB needles became available. In our study, 19-gauge FNA needle resulted in 45.5% level 1 and 2 histological diagnosis of AIP, consistent with previous studies [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe advent of FNB needles improved the efficacy for diagnosing AIP [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. FNB needles commonly used in current clinical practice include side-fenestrated forward-cutting beveled needles, reverse beveled needles, Franseen-tip needles, and fork-tip needles (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The FNB needle used in our study was the 20G side-fenestrated forward-cutting beveled needle (ProCore\u0026trade;), which contains a Menghini type tip and a straight bevel located on the proximal side of the lateral window, allowing the core trap to catch more tissue while the needle moves forward [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. This needle is now widely used by endoscopists worldwide. Compared with the earlier 22G reverse-beveled needle (ProCore\u0026trade;), the 20G needle offers better maneuverability and greater tissue acquisition [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Indeed, the histological accuracy of the 20G FNB needle has been reported to be as high as 96.4% in pancreatic carcinoma patients [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. For AIP, ~\u0026thinsp;45% of patients with highly-suggestive features of AIP were diagnosed with level 1 or 2 histological findings via the 20G forward-bevel FNB needle [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Some of the histological features of AIP like storiform fibrosis and obliterative phlebitis need more core tissue for their confirmation. Although we found that the proportion of cases with \u0026gt;\u0026thinsp;3 mm tissue acquisition with the 20G FNB needle was higher than that obtained with the 19G FNA needle, there was no difference in the proportion of level 1 or 2 diagnoses between the two groups, suggesting that obtaining tissue\u0026thinsp;\u0026gt;\u0026thinsp;3 mm might not be necessary to confirm the diagnosis of AIP.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIt is worth mentioning that Franseen and Forktip FNB needles both have good diagnostic performance for AIP. The 22G Franseen needle was reported to result in a higher proportion (78%) of level 1 or 2 histological findings compared with 20G forward-bevel FNB needles (45%) in AIP patients [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. The Asian EUS Group (AEG) recently developed guidelines regarding EUS-guided tissue acquisition [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e], which recommend the use of Franseen or fork-tip FNB needles in preference to side-bevel FNB needles, where feasible, when histological specimens are required from pancreatic lesions. However, the 22G Franseen and Forktip needles were not available at our center at the time of this study. Our present study suggests that for centers where FNB needles are not available, the 19G FNA needle might be an alternative and achieve similar diagnostic performance to the 20G FNB needle.\u003c/p\u003e \u003cp\u003eThis study has several limitations. First, most included cases were type 1 AIP and only two cases were diagnosed as type 2 AIP in the FNA group. There are very little published data on EUS-FNA or FNB in diagnosing type 2 AIP due to the rarity of the disease, and most studies have included no more than three cases of type 2 AIP [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan additionalcitationids=\"CR26 CR27\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e], as here. Nevertheless, under the assumption that more tissue acquisition is key to improving the diagnosing of both type 1 and type 2 AIP, our results can reasonably be applied to type 2 AIP. Second, our evaluation was based on tissue acquisition \u0026ldquo;per patient\u0026rdquo; instead of \u0026ldquo;per pass\u0026rdquo;. However, we punctured every patient twice in this study, minimizing potential over-rating of tissue acquisition.\u003c/p\u003e"},{"header":"CONCLUSIONS","content":"\u003cp\u003eIn summary, our study reveals that there is no difference in diagnostic efficacy or core tissue acquisition between the 19G FNA needle and the 20G forward-beveled FNB needle for patients with AIP. We suggest that the 19G FNA needle might be an alternative for centers where FNB needles are not available.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eAIP: Autoimmune pancreatitis\u003c/p\u003e\n\u003cp\u003eICDC: International Consensus Diagnostic Criteria\u003c/p\u003e\n\u003cp\u003eLPSP: Lymphoplasmacytic sclerosing pancreatitis\u003c/p\u003e\n\u003cp\u003eGELs: Granulocytic epithelial lesions\u003c/p\u003e\n\u003cp\u003eEUS: Endoscopic ultrasound\u003c/p\u003e\n\u003cp\u003eFNA: Fine needle aspiration\u003c/p\u003e\n\u003cp\u003eFNB: Fine needle biopsy\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u0026nbsp;\u003c/strong\u003eThe Peking Union Medical College Hospital Human Ethics Committee approved the study (number:\u0026nbsp;ZS-1767). All patients provided written informed consent.\u003c/p\u003e\n\u003cp\u003eConsent for publication: Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u0026nbsp;\u003c/strong\u003eThe datasets used and/or analysed during the current study are available from the corresponding authors on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eDrs. Wen Shi, Xiaoyan Chang, Shengyu Zhang, Tao Guo, Qingwei Jiang, Qiang Wang, Dongsheng Wu, Yanyan Wu, Yunlu Feng, and Aiming Yang have no conflicts of interest or financial ties to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eThis work was\u0026nbsp;supported by National High Level Hospital Clinical Research Funding [grant number 2022-PUMCH-B-024, 2022-PUMCH-A-177, 2022-PUMCH-A-076] and National Natural Science Foundation of China [grant number 32370946]\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions:\u0026nbsp;\u003c/strong\u003eStudy concept and design and paper preparation: W Shi, XY Chang, and YL Feng.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003ePaper preparation and Statistical analysis: W Shi, YL Feng, SY Zhang, and YY Wu.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003ePaper preparation and critical revisions: AM Yang, T Guo, X Wu, QW Jiang, Q Wang, and DS Wu.\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eDong Y, D\u0026apos;Onofrio M, Hocke M, Jenssen C, Potthoff A, Atkinson N, Ignee A, Dietrich CF. 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Effectiveness of introducing a 20-gauge core biopsy needle with a core trap in EUS-FNA/B for diagnosing pancreatic cancer. BMC Gastroenterol. 2021;21(1):8. 10.1186/s12876-020-01583-7\u003c/li\u003e\n\u003cli\u003eChong CC, Pittayanon R, Pausawasdi N, Bhatia V, Okuno N, Tang RS, Cheng TY, Kuo YT, Oh D, Song TJ, Kim TH. Consensus statements on endoscopic ultrasound-guided tissue acquisition. Guidelines from the Asian Endoscopic Ultrasound Group. Dig Endosc. 2024; Published online: 3 Mar 2024 10.1111/den.14768.\u003c/li\u003e\n\u003cli\u003eKanno A, Ishida K, Hamada S, Fujishima F, Unno J, Kume K, Kikuta K, Hirota M, Masamune A, Satoh K, Notohara K. Diagnosis of autoimmune pancreatitis by EUS-FNA by using a 22-gauge needle based on the International Consensus Diagnostic Criteria. Gastrointest Endosc. 2012;76(3):594-602. 10.1016/j.gie.2012.05.014\u003c/li\u003e\n\u003cli\u003eIshikawa T, Itoh A, Kawashima H, Ohno E, Matsubara H, Itoh Y, Nakamura Y, Hiramatsu T, Nakamura M, Miyahara R, Ohmiya N. Endoscopic ultrasound-guided fine needle aspiration in the differentiation of type 1 and type 2 autoimmune pancreatitis. World J Gastroenterol. 2012;18(29):3883-3888. 10.3748/wjg.v18.i29.3883\u003c/li\u003e\n\u003cli\u003eDetlefsen S, Joergensen MT, Mortensen MB. Microscopic findings in EUS-guided fine needle (SharkCore) biopsies with type 1 and type 2 autoimmune pancreatitis. Pathol Int. 2017;67(10):514-520. 10.1111/pin.12563\u003c/li\u003e\n\u003cli\u003eMatsumoto Y, Shimizu A, Ogawa K, Nakamura M, Hoki S, Kuroki S, Yano Y, Ikuta K, Senda E, Shio S. Late-onset type-2 autoimmune pancreatitis with two mass lesions diagnosed by endoscopic ultrasound-guided fine-needle aspiration. Clin J Gastroenterol. 2021;14(3):899-904. 10.1007/s12328-021-01364-z\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Autoimmune pancreatitis, EUS-FNA, EUS-FNB, needle, diagnostic performance, prospective randomized controlled trial","lastPublishedDoi":"10.21203/rs.3.rs-4407496/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4407496/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eThe diagnosis of autoimmune pancreatitis (AIP) is multidisciplinary, with the histopathological diagnosis providing crucial information for distinguishing AIP from malignancies. Here we compared the diagnostic performance and sample adequacy of 19-gauge endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) needles with 20-gauge endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) needles in patients with suspected AIP.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003ePatients with suspected AIP were enrolled between October 2018 and August 2020 into a single-center, prospective, randomized controlled study conducted at a tertiary medical center in Beijing. Participants were randomly assigned to undergo tissue specimen collection using either a 19-gauge EUS-FNA needle or a 20-gauge EUS-FNB needle. The primary endpoint was the sensitivity of the two needle types for diagnosing AIP, with secondary endpoints including diagnostic sufficiency of tissue obtained, technical success rate, adverse event rate, and contribution of histologic findings to the AIP diagnosis according to International Consensus Diagnostic Criteria.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eForty-five patients were enrolled. There was no significant difference in diagnostic efficacy between the 19-gauge FNA needle and the 20-gauge forward-beveled FNB needle for AIP. Both needle types showed similar sensitivity and overall accuracy in diagnosing benign disease, including AIP. The median tissue length was comparable between the two groups, and there was no significant difference in adverse events.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eThere is no difference in diagnostic efficacy or core tissue acquisition between 19-gauge FNA and 20-gauge forward-beveled FNB needles for patients with AIP. The 19-gauge FNA needle may serve as an alternative in centers where FNB needles are not available.\u003c/p\u003e\u003ch2\u003eTrial Registration\u003c/h2\u003e \u003cp\u003eClinicalTrials.gov NCT03753815\u003c/p\u003e","manuscriptTitle":"Comparison of 19-gauge aspiration needles with 20-gauge forward-bevel needles for the diagnosis of autoimmune pancreatitis: a prospective randomized, controlled study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-05-29 02:15:10","doi":"10.21203/rs.3.rs-4407496/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"bd2def09-d49c-40e4-a130-8c8d8b645e8f","owner":[],"postedDate":"May 29th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-11-13T20:53:26+00:00","versionOfRecord":[],"versionCreatedAt":"2024-05-29 02:15:10","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4407496","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4407496","identity":"rs-4407496","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}