A comparison of 4-Fr with 5-Fr endoscopic nasopancreatic drainage catheters: A randomized, controlled trial

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1 bs_bs_banner doi: /jgh GASTROENTEROLOGY A comparison of 4-Fr with 5-Fr endoscopic nasopancreatic drainage catheters: A randomized, controlled trial Teruo Mouri, Tamito Sasaki, Masahiro Serikawa, Takashi Ishigaki, Yasutaka Ishii, Akinori Shimizu, Tomofumi Tsuboi, Keisuke Kurihara, Yumiko Tatsukawa, Eisuke Miyaki, Ryota Kawamura, Ken Tsushima and Kazuaki Chayama Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Hiroshima, Japan Key words endoscopic nasopancreatic drainage, pancreatic cancer, post-endoscopic retrograde cholangiopancreatography pancreatitis, risk factor. Accepted for publication 3 February Correspondence Dr Teruo Mouri, Department of Gastroenterology and Metabolism, Hiroshima University Hospital, Kasumi, Minami-ku, Hiroshima, , Japan. d111261@hiroshima-u.ac.jp Abstract Background and Aim: Although endoscopic nasopancreatic drainage (ENPD) is useful for collecting samples for pancreatic juice cytology and for treating leakage of pancreatic juice and occlusive pancreatitis, placement of the ENPD catheter is associated with complications such as post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). We investigated whether an ENPD catheter with a smaller diameter could reduce the incidence of complications. Methods: Patients requiring placement of an ENPD catheter (n = 254) were enrolled and randomly assigned to one of two catheter-size groups: the 4-Fr group or the 5-Fr group. The incidence of PEP, cholangitis, and spontaneous catheter displacement and the suitability of pancreatic juice cytology samples were compared between groups. In addition, univariate and multivariate analyses were conducted on factors associated with PEP. Results: The incidence of PEP was significantly lower in the 4-Fr group compared with the 5-Fr group (4.1% vs 12.4%, respectively; P = 0.021). The rate of cholangitis and spontaneous catheter displacement and the suitability of pancreatic juice cytology samples did not differ between groups. Multivariate analysis revealed that the risk of PEP was 3.7 times higher when using a 5-Fr catheter than when using a 4-Fr catheter (P = 0.019). In addition, the risk of PEP was 4.1 times higher in patients with an intraductal papillary mucinous neoplasm than in those without (P = ) and 4.6 times higher in patients aged <65 than in those aged 65 (P = ). Conclusions: A 4-Fr catheter is as useful as a 5-Fr catheter and is associated with a significantly lower incidence of PEP. Introduction Pancreatic cancer is commonly diagnosed in the advanced state, and its prognosis is very poor compared with other malignant tumors. The poor prognosis may result from difficulty in detecting early pancreatic cancer on imaging studies. According to the Japan Pancreatic Cancer Registry of the Japan Pancreas Society, tumor size (TS) was equal to or greater than TS2 in 95% of patients and was found to be TS1 in only 5% of patients. 1 In addition, according to the same report, the 5-year survival rate for patients with a TS1a tumor with a diameter 10 mm was 80.4%, and patients in whom a tumor with a small size is detected can be expected to have a good prognosis. However, because there are stage IV cases even among patients with TS1a tumors, diagnosis at the stage of carcinoma in situ, in which a mass is not formed, is necessary for detecting curable pancreatic cancer. Endoscopic nasopancreatic drainage (ENPD), which is the external drainage of the pancreatic duct with an endoscope, was first reported by Huibregtse et al. 2 ENPD has been performed for treatment of leakage of pancreatic juice and pancreatic pseudo-cysts. 3,4 In addition, it has been reported in recent years that pancreatic juice cytology after placement of ENPD was effective for the diagnosis of early pancreatic carcinoma, and data on the placement of an ENPD catheter for diagnostic purposes have been presented. 5 7 When performing pancreatic juice cytology, we believe it is important to collect a sufficient volume of pancreatic juice as this increases the diagnostic accuracy, and collection of pancreatic juice only during endoscopic retrograde pancreatography is not sufficient. In order to accomplish this, the ENPD catheter is placed within the pancreatic duct, and the pancreatic juice is collected via natural drainage using a catheter. Contrast medium can also be injected through the catheter to perform lavage cytology. When the side hole of the catheter is located in the duodenum during ENPD catheter placement, pancreatic juice will leak into the duodenum, so it is important to place the side hole within the pancreatic duct. In order to avoid causing pancreatitis due to excessive contrast medium pressure when performing lavage cytology, the contrast medium should be used to lavage the pancreatic duct gradually in small volumes and under radiographic guidance; then a sample can be obtained. Because the ENPD catheter is placed into the pancreatic duct for a long period of time according to its purpose, the potential for the complication of acute 1783 This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

2 Comparison of 4- and 5-Fr catheters T. Mouri et al. pancreatitis is a concern. The mechanism of PEP onset after the placement of an ENPD catheter has not been elucidated, but occlusion of the branching pancreatic duct due to the ENPD catheter may be one cause. Therefore, we prepared a 4-Fr catheter and planned this study considering that a 4-Fr catheter may inhibit the pancreatitis caused by ENPD placement based on its smaller size compared with the standard 5-Fr catheter. Methods Study design. This was a single-center, parallel-group, prospective, randomized, controlled trial designed to assess patients who underwent nasopancreatic drainage with endoscopic retrograde cholangiopancreatography (ERCP). Enrolled patients were assigned randomly to one of two catheter-size groups. The study protocol is available at the University Hospital Medical Information Network Clinical Trial Registry (UMIN ). Setting. The study was performed at Hiroshima University Hospital, a tertiary care, academic medical center. Cases for inclusion. Patients who underwent ERCP and ENPD catheter placement from April 2011 to April 2015 at Hiroshima University Hospital were included in the study. Written informed consent was obtained from patients who planned to undergo ENPD catheter placement. ENPD catheter size was randomly assigned with the envelope method, during the stage of guidewire placement into the pancreatic duct, after selective cannulation into the pancreatic duct, and the prospective study was conducted. Patients were not informed of their assigned catheter size. Patient selection (indication of endoscopic nasopancreatic drainage). Inclusion criteria were the following: presence of a pancreatic mass, pancreatic duct narrowing/dilation, or pancreatic cyst judged to be necessary for cytodiagnosis or exclusion. Exclusion criteria were age < 20 years, pregnancy, history of endoscopic biliary sphincterotomy (EST) or endoscopic papillary balloon dilation, acute pancreatitis, serum pancreatic-type amylase count 3 times above normal before ERCP, pancreas divisum, pancreaticobiliary maljunction, sphincter of Oddi dysfunction, history of reconstructive surgery in the upper gastrointestinal tract (other than the Bil-1 technique), imminent EST or balloon dilation, planned insertion of a pancreatic duct stent, and allergy to the materials used in the procedure (polyethylene, polyurethane, or the ERCP contrast medium). 224 patients (112 per group) were needed. Assuming a 10% dropout rate, we calculated a final sample size of 240 patients. Endoscopic nasopancreatic drainage catheter. The ENPD catheter (Gadelius Medical K.K., Tokyo, Japan) was made of polyurethane. It had a looped shape from the papilla to the duodenal bulb, and its total length was 260 cm. The portion of the catheter that was inserted into the pancreas was 10 cm long and had a slight S shape. The 12 side holes were positioned in a helical pattern and were 0.6 mm in diameter on the 5 Fr and 0.4 mm on the 4 Fr. The external diameters of the 5- and 4-Fr ENPD catheters were 1.67 and 1.40 mm, respectively, and their internal diameters were 1.10 and 1.05 mm, respectively (Fig. 1). The 5- and 4-Fr ENPD catheters had the same shape; they differed only in width. Endoscopic retrograde cholangiopancreatography and endoscopic nasopancreatic drainage catheter placement. The ionic contrast medium iothalamate meglumine (Conray 60% injection; Daiichi Sankyo Corporation, Ltd., Tokyo, Japan) was used for ERCP. After pancreatography was performed with the contrast medium, selective cannulation was performed (PR-110Q; Olympus Corporation, Tokyo, Japan), and a in. guidewire (Wrangler; Piolax Medical Devices, Inc., Yokohama, Japan) was guided into the distal pancreatic duct. When necessary, intraductal ultrasound (IDUS), brushing of the pancreatic duct, and biopsy of the papilla Vater were performed. The ENPD catheter was inserted over the guidewire (Fig. 2). When cholangiography or bile duct treatment was necessary, the bile duct procedure was performed during the same session. Follow-up. Immediately after ERCP, patients were given either nafamostat mesilate 20 mg/day or ulinastatin U/day for 2 days. Prophylactic antibiotics were not administered. Postprocedural clinical symptoms were carefully observed, and blood samples were taken after 2 and 18 h to monitor for the presence or absence of complications. When adverse events were suspected to have occurred after catheter insertion, the physician in charge removed the catheter. Sample size calculation. Because the incidence of PEP associated with ENPD catheter placement has not been reported, it was inferred. A randomized comparative study on placement of a pancreatic stent for the purpose of prevention of PEP showed that the rate of PEP after placement was 0 20% It was assumed that the rate of PEP with a 5-Fr ENPD catheter was 13%, and the rate of PEP with a 4-Fr ENPD catheter was 3%. Using a statistical power of 80%, with the assumption of a 0.05 alpha level with a two-sided Fisher s exact test, we determined that Figure 1 Comparison of 4- and 5-Fr nasopancreatic drainage catheters. (a) Upper catheter, 5 Fr; lower catheter, 4 Fr. Both have the same looped configuration. (b) Cross-sectional view: left, 4 Fr; right, 5 Fr. 1784

3 T. Mouri et al. Comparison of 4- and 5-Fr catheters Figure 2 Cholangiopancreatography and nasopancreatic drainage catheter placement. (a) The contrast medium was injected into the pancreatic duct. (b) The guidewire was introduced into the distal pancreatic duct. (c) Final form of the nasopancreatic drainage catheter. Cytodiagnosis. The day after ERCP, pancreatography was performed with a contrast medium after checking for catheter displacement under fluoroscopic guidance. When cytodiagnosis was necessary, samples of pancreatic juice were collected. For pancreatic juice cytology, Papanicolaou staining was performed with conventional methods, and results were evaluated by an expert cytoscreener. The suitability of samples was evaluated based on the degree of denaturation and whether the volume of the sample was sufficient to make a diagnosis. Date record. Patients age, sex, height, weight, body mass index, indication for ERCP, type of procedure performed during ERCP, total ERCP time, and final diagnosis were recorded. Blood samples were taken after 2 and 18 h, and pancreatic-type amylase, hepatic enzymes (aspartate aminotransferase and alanine aminotransferase), biliary enzymes (alkaline phosphatase and gammaglutamyl transpeptidase), total bilirubin, C-reactive protein, and complete blood count were measured. The visual analog scale (VAS) discomfort scores on both the procedure day and the following day were recorded. End-point. The primary end-point was the rate of PEP. PEP was defined as postoperative abdominal pain according to the Cotton classification 17 and 3 times the upper limit of normal for blood pancreatic enzymes. In cases suspected to have PEP, contrast computed tomography was performed, and the severity of pancreatitis was evaluated according to the Cotton classification. 17 Various clinical factors associated with PEP onset were investigated in univariate and multivariate analyses. The secondary end-points were the rate of cholangitis, the rate of spontaneous catheter displacement within 24 h of placement, the suitability of pancreatic juice cytology samples, and nose and throat discomfort. Discomfort was evaluated on the day of and the day after the procedure with VAS in which 0 denotes no discomfort and 10 denotes intensified discomfort. Statistical analysis. Statistical analysis was performed with JMP 12 (SAS Institute, Inc., Cary, NC, USA). Fisher s exact probability test, chi-squared test, Mann Whitney U-test, and logistic regression analysis were performed, and P < 0.05 was considered significant. All analyses were performed on an intention-to-treat basis. We first performed a univariate analysis for each potential risk factor. We then performed a multivariate (logistic regression) analysis using only the significant factors (P < 0.1 and odds ratio [OR] > 1) detected during univariate analysis. 1785

4 Comparison of 4- and 5-Fr catheters T. Mouri et al. Results Patient flow and baseline characteristics. Written informed consent was obtained from 254 patients. Of these, 11 patients were excluded: in six, serum pancreatic amylase levels were 3 times normal before ERCP; in two, the ENPD catheter was placed into the minor papilla; in two, another ENPD catheter was used; and in one patient, a biliary stent was placed in addition to an ENPD catheter. The remaining 243 patients (137 men and 106 women; mean age, 66.7 years; range, years) were enrolled in the study. Among them, 122 were assigned to the 4-Fr group, and 121 were assigned to the 5-Fr group (Fig. 3). Placement of the ENPD catheter was successful in all cases in both the 4-Fr group and the 5-Fr group. Patient baseline characteristics are summarized in Table 1. No significant difference was found between groups in patient background, indication for placement of an ENPD catheter, final diagnosis, and ERCP procedure (Table 1). Primary outcome measure. The rate of PEP was 4.1% (5/ 122) in the 4-Fr group and 12.4% (15/121) in the 5-Fr group. The rate of PEP was significantly lower in the 4-Fr group than in the 5-Fr group (P = 0.021). The severity of pancreatitis was mild in four cases and moderate in one case in the 4-Fr group and mild in 14 cases and moderate in one case in the 5-Fr group (Table 2). Pancreatitis subsided with conservative treatment in all patients. Secondary outcome measures. The rate of cholangitis, which was 2.5% (3/122) in the 4-Fr group and 6.6% (8/121) in the 5-Fr group, did not differ significantly between the two groups (P = 0.136). Within 24 h of ENPD catheter insertion, 3 ENPD catheters had been removed by patients (4 Fr: n = 1; 5 Fr: n = 2), and 16 had been removed by physicians due to suspicion of an adverse event, such as retention of pancreatic juice and retention of bile juice (4 Fr: n = 7; 5 Fr: n = 9). The rate of spontaneous displacement, which was 2.5% (3/122) in the 4-Fr group and 1.7% (2/121) in the 5-Fr group, did not differ significantly between the two groups (P = 1). Pancreatic juice cytodiagnosis was carried out in the 219 cases whose ENPD catheter remained in the pancreatic duct until the day after insertion (Fig. 3). Unsuitable samples were found in 11 cases in the 4-Fr group and 12 cases in the 5-Fr group. The suitability of pancreatic juice samples was 82.0% (100/122) in the 4- Fr group and 79.3% (96/121) in the 5-Fr group and did not differ significantly between the two groups (P = 0.604). In the subgroup analysis of the 219 patients for whom it was possible to make a cytodiagnosis, the percentage of suitable pancreatic juice samples, which was 90.1% (100/111) in the 4-Fr group and 88.9% (96/108) in the 5-Fr group, did not differ significantly between the two groups (P = 0.772). The VAS score for discomfort against ENPD, which was 2.9 ± 2.7 in the 4-Fr group and 3.5 ± 2.5 in the 5-Fr group (P = 0.129) on the examination day and 2.8 ± 2.6 in the 4-Fr group and 2.8 ± 2.4 in the 5-Fr group (P = 0.509) on the following examination day, did not differ significantly between the two groups (Table 2). Risk factors for post-endoscopic retrograde cholangiopancreatography pancreatitis. The various clinical factors associated with PEP onset were investigated in a univariate analysis (Table 3). Younger persons are at higher risk for PEP compared with older persons. Examination procedures, including cholangiography, IDUS, brushing cytodiagnosis, papillary biopsy, and examination time were not risk factors for PEP, but with regard to ENPD catheter size, the 4-Fr group had a significantly reduced risk of PEP compared with the 5-Fr group (OR 3.3, 95% confidence interval [CI] 1.2, 9.4, P = 0.021). The risk factor for PEP after ENPD regarding diagnosis was intraductal papillary mucinous neoplasm (IPMN). PEP was not observed in patients with pancreatic cancer. Multivariate analysis showed that the risk of PEP was 3.7 times higher when using a 5-Fr catheter than when using a 4-Fr catheter (OR 3.7, 95%CI 1.3, 12, P = 0.019). In addition, the risk of PEP increased 4.1 times with ENPD catheter placement for IPMN compared with placement for non-ipmn cases (OR 4.1, 95%CI 1.6, 12, P = ), and it was 4.6 times higher for those aged <65 years compared with those aged 65 years (OR 4.6, 95%CI 1.7, 13, P = ) (Table 3). Figure 3 Study flow chart. Intention-to-treat analysis was performed. Discussion Endoscopic nasopancreatic drainage is not only used for external drainage for treatment of pancreatic pseudo-cysts and leakage of pancreatic juice but also used aggressively for cytodiagnosis, aimed at the diagnosis of early pancreatic cancer and carcinoma in situ. 5 7,18 22 However, the safety of the placement of an ENPD catheter has not been reported. In this study, we investigated whether an ENPD catheter with a smaller diameter would be associated with PEP. Results showed that the rate of PEP was 12.4% in the 5-Fr group, while it was 4.1% in the 4-Fr group, showing that the rate of PEP was significantly lower in the 4-Fr group. The outer diameter of the 5-Fr catheter was 1.67 mm, while that of the 4-Fr catheter was 1.40 mm. Considering that the diameter of a normal pancreatic duct is about 2 mm, a smaller outer catheter diameter is advantageous in not occluding the branching pancreatic duct. The influence on branching pancreatic duct is considered to 1786

5 T. Mouri et al. Comparison of 4- and 5-Fr catheters Table 1 Patient characteristics and procedure details 4-Fr group (n = 122) 5-Fr group (n = 121) Overall (n = 243) P-value Age (year), mean (SD) 66.1 (12.6) 67.3 (10.3) 66.7 (11.5) 0.51 Sex Male 65 (53.3) 72 (59.5) 137 (56.4) 0.33 Female 57 (46.7) 49 (40.5) 106 (43.6) Body mass index (kg/m 2 ), mean (SD) 22.6 (3.1) 22.4 (3.0) 22.5 (3.1) 0.52 Indication Pancreatic mass 33 (27.0) 35 (28.9) 68 (28.0) 0.74 Pancreatic duct stenosis/dilatation 31 (25.4) 31 (25.6) 62 (25.5) 0.97 Pancreatic cyst 58 (47.5) 55 (45.5) 113 (46.5) 0.74 Final diagnosis Pancreatic ductal carcinoma 21 (17.2) 28 (23.1) 49 (20.2) 0.25 Intraductal papillary mucinous neoplasm 35 (28.7) 36 (29.8) 71 (29.2) 0.86 Other pancreatic neoplasm 17 (13.9) 12 (9.9) 29 (11.9) 0.33 Pancreatic cyst 13 (10.7) 11 (9.1) 24 (9.9) 0.68 Autoimmune pancreatitis 9 (7.4) 4 (3.3) 13 (5.3) 0.25 Chronic pancreatitis 12 (9.8) 19 (15.7) 31 (12.8) 0.17 Papilla of Vater tumor 2 (1.6) 0 (0) 2 (0.8) 0.50 Others 13 (10.7) 11 (9.1) 24 (9.9) 0.68 Endoscopic retrograde cholangiopancreatography procedures Failed cannulation Bile duct injection 66 (54.1) 71 (58.7) 137 (56.4) 0.47 Pancreatic duct injection Pancreatic intraductal ultrasonography 21 (17.2) 25 (20.7) 46 (18.9) 0.49 Brushing of pancreatic duct 13 (10.7) 20 (16.5) 33 (13.6) 0.19 Biopsy of papilla of Vater 3 (2.5) 2 (1.7) 5 (2.1) 1 Procedure time (min), mean (SD) 26.9 (10.7) 26 (8.6) 26.5 (9.7) 0.52 Table 2 Outcomes 4-Fr group (n = 122) 5-Fr group (n = 121) Overall (n = 243) P-value Pancreatitis Total 5 (4.1) 15 (12.4) 20 (8.2) Severity Mild 4 (3.3) 14 (11.6) 18 (7.4) Moderate 1 (0.8) 1 (0.8) 2 (0.8) Severe 0 (0) 0 (0) 0 (0) Cholangitis 3 (2.5) 8 (6.6) 11 (4.5) Catheter displacement Physician removal 7 (5.7) 9 (7.4) 16 (6.6) Patient self-removal 1 (0.8) 2 (1.7) 3 (1.2) Spontaneous displacement 3 (2.5) 2 (1.7) 5 (2.1) 1 No displacement 111 (91.0) 108 (89.3) 219 (90.1) Cytodiagnosis (next day) Proper specimen 100 (82.0) 96 (79.3) 196 (80.7) Improper specimen 11 (9.0) 12 (9.9) 23 (9.5) Visual analog scale discomfort score Procedure day, mean (SD) 2.9 (2.7) 3.5 (2.5) 3.2 (2.6) Post-procedure day 1, mean (SD) 2.8 (2.6) 2.8 (2.4) 2.8 (2.5) Values are given as n (%) except where noted. Significant difference. lead to the difference in PEP incidence between 4 and 5 Fr. On the other hand, no significant difference was observed for cholangitis, spontaneous catheter displacement, and suitability of pancreatic juice cytology between the 4-Fr group and the 5-Fr group. A 4-Fr 1787

6 Comparison of 4- and 5-Fr catheters T. Mouri et al. Table 3 Risk factors for PEP after ENPD PEP(+) PEP(-) Univariate analysis Multivariate analysis (n = 20) (n = 223) OR 95%CI P-value OR 95%CI P-value Age < , , Female gender , Body mass index , Fr ENPD , , Bile duct injection , Pancreatic intraductal ultrasonography , Brushing of pancreatic duct Biopsy of papilla Vater Procedure time 30 min , Pancreatic ductal carcinoma Intraductal papillary mucinous neoplasm , , Other pancreatic tumors , Pancreatic cyst , Autoimmune pancreatitis Chronic pancreatitis , Papilla Vater tumor ENPD, endoscopic nasopancreatic drainage; OR, odds ratio; PEP, post-endoscopic retrograde cholangiopancreatography pancreatitis. Significant difference. catheter is equivalent to a 5-Fr catheter in functional aspects. In addition, although a catheter with a smaller diameter may reduce discomfort in the nose and throat, this study showed no significant difference in VAS scores between the two groups. Various risk factors are involved in PEP, including patient factors such as Oddi sphincter dysfunction, younger age, female gender, past history of pancreatitis, injured pancreatic duct due to pancreatography, IDUS and brushing of the pancreatic duct, and pancreatic juice outflow disturbance due to papillary edema and papillary sphincter spasm In our present study, IDUS was performed in 46 cases (1 case with pancreatic duct cancer, 39 cases with IPMN, 2 cases with a pancreatic cyst, and 4 cases with other), and brushing of the pancreatic duct was performed in 33 cases (22 cases with pancreatic duct cancer, 2 cases with IPMN, 3 cases with autoimmune pancreatitis, 4 cases with chronic pancreatitis, and 2 cases with other). Among them, PEP was seen in two of 46 IDUS cases, and PEP was not observed in 33 cases with brushing of the pancreatic duct. In the present study, IDUS and brushing of the pancreatic duct, which are risk factors for PEP, did not increase the incidence of PEP by placement of the ENPD catheter after the procedures. This may be because most of the patients who underwent these procedures had caudal pancreatic atrophy by narrowing from pancreatic cancer and chronic retention of pancreatic juice caused by IPMN and may have had reduced pancreatic function. In addition, the placement of the ENPD catheter into the caudal pancreatic duct, even with IDUS and brushing of the pancreatic duct may inhibit PEP. For the prevention of PEP, the usefulness of an endoscopic pancreatic duct stent (EPS) has been reported These reports showed that placement of the EPS contributes to the reduction of PEP in high-risk groups. In the present study, the incidence of PEP was significantly lower in the 4-Fr group, suggesting that placement of a 4-Fr ENPD catheter is as effective as EPS for preventing PEP. In multivariate analysis, younger age and IPMN were extracted as independent risk factors in addition to catheter size. The reason for the high incidence of PEP in IPMN was that the catheter was easy to occlude because of mucus with high viscosity. Harada reported that placement of a stent for IPMN increased the incidence of PEP significantly, 28 in agreement with our results. In the 2012 International Consensus Guidelines for the Management of IPMN and MCN of the Pancreas, 29 pancreatic juice cytodiagnosis is positioned as an adjunct diagnosis. Intraductal papillary mucinous carcinoma not accompanied by node with contrast effect and main pancreatic duct extension was present, and pancreatic cytodiagnosis is possibly effective in such a case. In typical cases of pancreatic cancer, repeated pancreatic juice cytodiagnosis with placement of ENPD increases the accuracy of pancreatic juice cytodiagnosis, but the placement should be carefully performed, noting that ENPD placement for IPMN is associated with a high risk of PEP. The present study had limitations. Because it was carried out at a single institution, bias in the selection of cases and procedural bias is possible. Additional studies may be necessary in multiple institutions to solve this problem. Conclusion The 4-Fr ENPD catheter was equal to the 5-Fr ENPD catheter in suitability of pancreatic juice cytodiagnosis and had a significantly lower PEP complication rate. We suggest that the 4-Fr ENPD catheter has the potential to become a standard catheter. References 1 Egawa S, Toma H, Ohigashi H et al. Japan Pancreatic Cancer Registry; 30th year anniversary. Pancreas 2012; 41: Huibregtse K, Schneider B, Vrij AA, Tytgat GN. Endoscopic pancreatic drainage in chronic pancreatitis. Gastrointest. Endosc. 1988; 34:

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