Obstruction Of Main Pancreatic Duct Research Articles

Risk factors for post-endoscopic retrograde pancreatography pancreatitis in malignant extrahepatic biliary obstruction: a retrospective single-center study

Background. Decompression interventions under the endoscopic retrograde cholangiopancreatography (ERCP) is the method of choice in malignant extrahepatic biliary obstruction (MEHBO). Acute pancreatitis is the most common complication of ERCP. Many studies have been performed to identify the risk factors for post-ERCP pancreatitis (PEP). However, these works in general include the analysis of ERCP in patients with various causes of biliary obstruction without subdividing patients with malignant obstruction.
 Purpose.The aim of this study was to determine the risk factors for PEP in patients with MEHBO.
 Materials and Methods. A retrospective analysis of 100 cases of ERCP in MEHBO was done. PEP was in 2 patients, and 14 patients had hyperamylasemia (HA). The following factors were analyzed: gender, age, level of MEHBO, obstruction of the main pancreatic duct (MPD), total bilirubin level, history of endoscopic papillosphincterotomy (EPST), periampullary diverticulum, successful ERCP, primary selective biliary cannulation, catheterization and/or contrast injection into MPD, Precut EPST, successful decompression.
 Results and discussion. Univariate analysis showed that PEP is associated with an obstruction at the level of the proximal and middle third of the hepaticocholedochus (p = 0.004) and with absence of MPD obstruction (p = 0.022); female gender (p = 0.012), obstruction at the level of the proximal and middle third of the hepaticocholedochus (p < 0.001), absence of MPD obstruction (p < 0.001), catheterization and/or contrast injection into MPD (p = 0.040) are associated with PEP or hyperamylasemia (HA); female gender (p = 0.024), obstruction at the level of the proximal and middle third of the hepaticocholedochus (p < 0.001), absence of MPD obstruction (p=0.006), catheterization and/or contrast injection into MPD (p = 0.035), successful decompression (p = 0.004) are associated with HA. Multivariate regression analysis showed that, for PEP and for PEP or HA as well as for HA, the risk factors are obstruction at the level of the proximal and middle third of the hepaticocholedochus (p = 0.005; p < 0.001; p < 0.001, respectively) and absence of MPD obstruction (p = 0.022; p < 0.001; p = 0.008, respectively). Female gender is a risk factor for PEP or HA and HA (p = 0.011; p = 0.028, respectively), and catheterization and/or contrast injection into MPD are risk factors for PEP or HA (p = 0.04). Conclusion. Development of PEP in MEHBO depends on the localization of a tumor and involvement of the pancreas. The risk factors for PEP in MEHBO are tumor localization at the level of the middle and proximal third of the hepaticocholedochus and absence of MPD obstruction.

Techniques and Outcomes of Endoscopic Ultrasound Guided—Pancreatic Duct Drainage (EUS- PDD)

Endoscopic ultrasound guided-pancreatic duct drainage (EUS- PDD) is one of the most technically challenging procedures for the interventional endoscopist. The most common indications for EUS- PDD are patients with main pancreatic duct obstruction who have failed conventional endoscopic retrograde pancreatography (ERP) drainage or those with surgically altered anatomy. EUS- PDD can be performed via two approaches: the EUS-rendezvous (EUS- RV) or the EUS-transmural drainage (TMD) techniques. The purpose of this review is to provide an updated review of the techniques and equipment available for EUS- PDD and the outcomes of EUS- PDD reported in the literature. Recent developments and future directions surrounding the procedure will also be discussed.

Structural imaging findings are related to clinical complications in chronic pancreatitis.

Background/objectivesStructural pancreatic changes and complications related to chronic pancreatitis are well described, but little is known about their relationship. We aimed to explore the associations between pancreatic morphology and clinical complications in a large chronic pancreatitis cohort.MethodsThe Scandinavian Baltic Pancreatic Club database collects registrations on patients with definite or probable chronic pancreatitis according to the M‐ANNHEIM diagnostic criteria. In this cross‐sectional study, we used multivariate logistic regression analyses to evaluate whether imaging‐based structural pancreatic changes were associated with common clinical complications. We adjusted for sex, age, disease duration, current alcohol abuse and current smoking.ResultsWe included 742 patients with a mean age of 55 years. Among these, 68% were males, 69% had pancreatic exocrine insufficiency, 35% had diabetes, 12% were underweighted and 68% reported abdominal pain. Main pancreatic duct obstruction, severe (i.e. more than 14) calcifications, pancreatic atrophy and parenchymal changes throughout the entire pancreas (continuous organ involvement) were positively associated with pancreatic exocrine insufficiency. Continuous organ involvement and pseudocysts were positively and negatively associated with diabetes, respectively. Pancreatic atrophy and severe calcifications were positively associated with underweight, and severe calcifications were negatively associated with pain.ConclusionsThis study shows independent associations between distinct structural changes on pancreatic imaging and clinical complications in chronic pancreatitis. Pancreatic atrophy, severe calcifications and continuous organ involvement may be of particular clinical relevance, and these findings should motivate monitoring of pancreatic function and nutritional status.

Safety and efficacy of EUS-guided pancreatic duct drainage in symptomatic main pancreatic duct obstruction: Is there still a place for surgery?

Abstract Background and study aims In patients with symptomatic dilation of the main pancreatic duct (MPD) for whom endoscopic retrograde cholangiopancreatography (ERCP) is impossible, surgery has long been the only available treatment. EUS-PD is described as a minimally invasive alternative for ductal decompression surgery. We describe the results of our experience with it. Patients and methods This was a retrospective single-center study over 9 years. Twenty-seven patients, median age 61.8 years (range 36 to 85) who underwent EUS-PD for symptomatic MPD dilatation were included. The main objective was to evaluate the technical success (placement of a plastic stent between the stomach and the MPD). Secondary objectives were to document clinical success based on pain and quality of life (visual analogic scales and treatments) and complication rates, and to define a standardized management algorithm. Results The technical success rate was 92.5 %. The rate of minor adverse events was 21 % (4 cases of non-specific postoperative pain and two cases of delayed benign edematous pancreatitis). The clinical success rate was 88 %, and half of patients in whom the procedure was successful had "complete regression" of pain and half "partial regression." Median follow-up was 34.2 months (range 4 to 108). During follow-up, 74 % of patients reported improvement in quality of life and no patients required secondary surgery. Conclusion Provided it is performed in an expert center, EUS-PD is a minimally invasive, effective, and safe alternative to pancreatic surgical drainage in patients with symptomatic MPD dilatation with failure or in whom ERCP is impossible.

Impact of physiologically shaped pancreatic stent for chronic pancreatitis

Endoscopic pancreatic stenting is used to prevent main pancreatic duct obstruction and relieve painful symptoms of chronic pancreatitis. However, the stent typically needs to be exchanged and the rate of adverse events is high. Few studies have evaluated the effect of stent shape on those outcomes. We evaluated the adverse events, stent patency, and total medical cost within 90 days of patients who received an 8.5 French (Fr) physiologically shaped pancreatic stent by comparing these features with those associated with a conventional straight-type stent for ≥ 90 days. The total stent-related adverse event rate was significantly lower for the physiologically shaped pancreatic stent (physiologically shaped, 6.7% [2/30]; straight-type, 50.6% [44/87]; P < 0.001). Stent occlusion was significantly less frequent (P < 0.001) and the total medical costs were significantly lower (P = 0.002) for the physiologically shaped stent. The stent-related adverse event rate was significantly higher for the 10 Fr straight type stent than for the 8.5 Fr physiologically shaped stent (10 Fr, straight-type vs. 8.5 Fr, physiologically shaped: 36.1% [13/36] vs. 6.7% [2/30]; P = 0.007). In conclusion, a physiologically shaped pancreatic stent was superior to a straight-type stent in terms of the patency rate and medical costs.

Pancreatic Cancer–Associated Diabetes is Clinically Distinguishable From Conventional Diabetes

BackgroundType 3c diabetes mellitus (T3cDM) is diabetes secondary to other pancreatic diseases such as chronic pancreatitis, pancreatic resection, cystic fibrosis, and pancreatic ductal adenocarcinoma (PDA). Clinically, it may easily be confused with conventional type 2 diabetes mellitus (T2DM). A delay in pancreatic cancer diagnosis and treatment leads to a worse outcome. Therefore, early recognition of PDA-associated T3cDM and distinction from conventional T2DM represents an opportunity improve survival in patients with PDA. MethodsSix hundred and sixty four patients with PDA underwent pancreatic resection. Patients were classified as per whether or not they had diabetes. The specific type of diabetes was determined. T3cDM surgical patients (n = 127) were compared with a control group of medical patients with T2DM who did not have PDA (n = 127). ResultsPatients with T3cDM were older (66 versus 61 y, P < 0.001), had lower body mass indices (25.9 versus 32.1, P < 0.001), more favorable hemoglobin A1c levels (7.0 versus 8.8, P < 0.001), higher alanine aminotransferase levels (39 versus 20, P < 0.001), and lower creatinine levels (0.8 versus 0.9 mg/dL, P < 0.001). In addition, they were more likely to be insulin dependent. In a subgroup analysis of surgical patients, T3cDM (versus surgical patients with T2DM and no diabetes) was not associated with surrogate markers of main pancreatic duct obstruction and glandular atrophy. ConclusionsPDA-associated T3cDM has a distinctive presenting phenotype compared with medical patients with conventional T2DM. Greater attention to associated signs, symptoms, and biochemical data could identify patients at risk for harboring an underlying pancreatic malignancy and trigger diagnostic pathways leading to earlier PDA diagnosis and treatment.

Prevention of Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis by Endoscopic Pancreatic Stenting after Insertion of Self-Expandable Metal Stent for Malignant Distal Biliary Stricture

The insertion of a self-expandable metal stent (SEMS) for nonpancreatic cancer is a factor predicting the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). We evaluated the efficacy of endo-scopic pancreatic stenting (EPS) to prevent PEP after SEMS insertion in patients with malignant distal biliary stricture and without main pancreatic duct (MPD) obstruction. We performed a single-center, retrospective, historically controlled investigation to assess the outcomes of 33 consecutive patients who underwent SEMS insertion. From March 2013 to June 2015, 13 patients did not undergo EPS (Non-EPS group). The other 20 patients underwent EPS (EPS group) between July 2015 and August 2018. The background data demonstrated no significant differences. Except for one patient in the Non-EPS group, all patients underwent biliary sphinc-terotomy. The EPS group's PEP incidence was significantly lower (n = 1, 5%) than that of the Non-EPS group (n = 4, 31%) (p = 0.04). The median serum amylase and lipase levels after the procedure were significantly lower in the EPS group than in the Non-EPS group (amylase: 104 vs. 262 U/L; p < 0.01, lipase: 102 vs. 666 U/L; p = 0.01). The use of EPS decreased the incidence of PEP after SEMS insertion in individuals with malignant distal biliary stricture and without MPD obstruction.

Inutility of endoscopic sphincterotomy to prevent pancreatitis after biliary metal stent placement in the patients without pancreatic duct obstruction

Background: The incidence of post-ERCP pancreatitis (PEP) has been reported to be significantly higher in patients without main pancreatic duct (MPD) obstruction who undergo transpapillary biliary metal stent (MS) placement than in those with ordinary ERCP setting.Objective: To evaluate the benefit of endoscopic sphincterotomy (ES) prior to MS placement in preventing PEP in patients with distal malignant biliary obstruction (MBO) without MPD obstruction.Materials and methods: In total, 160 patients who underwent initial MS placement for MBO were enrolled. Eighty-two patients underwent ES immediately prior to MS placement, whereas 78 underwent MS placement without ES. An inverse probability of treatment weighting method was adopted to adjust the differences of the patients’ characteristics. The primary outcome was the incidence of PEP. The secondary outcomes included the incidence of other adverse events (bleeding, cholangitis, perforation and stent dislocation) and time to recurrent biliary obstruction.Results: The incidence of PEP was 26.8% in the ES and 23.1% in the non-ES (unadjusted odds ratio [OR] [95%CI]: 1.22, [0.60–2.51], adjusted OR [95%CI]: 1.23, [0.53–2.81], p = .63). Logistic-regression analysis revealed no factors that could be attributed to the occurrence of PEP. The incidence of other adverse events was not different between the groups. The median time to recurrent biliary obstruction was 131 (2–465) days and 200 (4–864) days in the ES and non-ES, respectively (p = .215).Conclusions: ES prior to MS placement for patients with distal MBO without MPD obstruction does not reduce the incidence of PEP.

Multiple stents are not superior to single stent insertion for pain relief in patients with chronic pancreatitis: a retrospective comparative study.

Background and study aims Patients with painful chronic pancreatitis (CP) and distal main pancreatic duct (MPD) stricture are considered candidates for treatment using a single plastic stent insertion. Multiple side-by-side stents have been proposed as an alternative treatment but comparative studies are lacking. The aim of this retrospective study is to assess differences in characteristics and treatment outcomes in patients with CP and MPD strictures treated with a different number of stents during the stenting period. Patients and methods Patients with painful CP and distal MPD obstruction requiring endoscopic treatment (01.2004 – 12.2012) were considered. The study population was divided in three groups: Patients treated with (A) exclusively one stent; (B) one or two stents; and (C) exclusively two stents during the stenting period. Patient characteristics and treatment outcomes were retrospectively assessed. Results Among 284 patients, 85 were selected according to inclusion criteria (Group A: 18, Group B: 35, Group C: 32). Median follow-up duration was 84 months. The median number of endoscopic procedures needed was higher for group B [3 (A) vs. 3 (C) vs. 4 (B), P = 0.001]. Regarding outcome, successful endoscopic treatment was lower in Group C (50 % vs. 88.2 % and 74.2 % for groups A and B, respectively; P = 0.02). This difference was attributed to better clinical outcome in Group A compared to Group C patients [OR(95%CI): 7.50 (1.46 – 38.70); P = 0.04]. Moreover, group C patients experienced higher levels of pain at the end of follow-up period [median Izbicki Score 0 (group A) vs. 0 (group B) vs. 6 (group C), P = 0.03]. Conclusions In patients with painful CP and distal MPD obstruction, treatment with a single stent is associated with better clinical outcome compared to treatment with exclusively two stents during the stenting period.

Anterograde Endoscopic Ultrasound-Guided Pancreatic Duct Drainage: A Technical Review.

The advancement of pancreatic endotherapy has increased the availability of minimally invasive endoscopic pancreatic ductal drainage techniques. In this regard, familiarity with endoscopic ultrasound-guided pancreatic duct drainage (EUS-PDD) is critical for treatment of obstructed pancreatic ductal systems, especially in nonsurgical candidates and in patients desiring a minimally invasive approach. Two distinct forms of EUS-PDD exist, viz. rendezvous-assisted endoscopic retrograde pancreatography (rendezvous-assisted ERP) and anterograde EUS-PDD. Anterograde EUS-PDD refers to transmural anterograde passage of a pancreatic drainage catheter or stent directly into the main pancreatic duct, through either the gastric or enteral wall. Rendezvous-assisted ERP should be attempted after failed conventional ERP, and anterograde EUS-PDD should be considered if rendezvous-assisted ERP fails or is not technically feasible. Common clinical scenarios that fulfil these conditions are chronic pancreatitis with high-grade main pancreatic duct obstruction, surgically altered anatomy with ductal/anastomotic obstruction, pancreas divisum, and disconnected pancreatic duct syndrome. The focus of this review article is anterograde EUS-PDD and its indications, technique, and outcomes. It also provides a summary of our own experience with this procedure, and a video demonstration of the technique.

337 ENDOSCOPIC ULTRASOUND (OLYMPUS MINIPROBE) ASSISTED RETROGRADE PANCREATIC DUCT ACCESS IN PATIENTS WITH COMPLETE STENOSIS OF PANCREATICOJEJUNOSTOMY AFTER WHIPPLE SURGERY

337 ENDOSCOPIC ULTRASOUND (OLYMPUS MINIPROBE) ASSISTED RETROGRADE PANCREATIC DUCT ACCESS IN PATIENTS WITH COMPLETE STENOSIS OF PANCREATICOJEJUNOSTOMY AFTER WHIPPLE SURGERY

Frequency, Severity, and Risk Factors for Acute Pancreatitis After Percutaneous Transhepatic Biliary Stent Placement Across the Papilla of Vater.

To clarify the frequency, severity, and risk factors for acute pancreatitis after percutaneous biliary stent placement across the papilla of Vater for malignant biliary obstruction. This retrospective study included 95 patients who underwent percutaneous biliary metallic stent placement (64 [67.4%] bare stents and 31 [32.6%] covered stents) across the papilla of Vater for malignant biliary obstruction between January 2010 and December 2012. The incidence of acute pancreatitis (Atlanta classification of acute pancreatitis) and its severity (Common Terminology Criteria for Adverse Events, version 4) were reviewed. Additionally, the characteristics of the patients and biliary stents, and the computed tomography findings of the pancreas were evaluated. Grade 3 acute pancreatitis was observed in 23 patients (24.2%); acute pancreatitis of grade 4 or higher was not observed. The incidence of acute pancreatitis was lower in patients with atrophic pancreas than in those with non-atrophic pancreas (7.5 vs. 36.4%, p=0.004). It was also lower in patients with main pancreatic duct (MPD) obstruction than in those without MPD obstruction (12.5 vs. 36.2%, p=0.026). There was no difference in the incidence of acute pancreatitis between bare and covered stents. Percutaneous biliary stent placement across the papilla of Vater for malignant biliary stricture caused acute pancreatitis requiring medication in 24.2% of patients. Atrophy of the pancreas and the presence of a dilated MPD may be associated with a decreased risk of acute pancreatitis. Level 4, Case Series.

Efficacy of endoscopic ultrasonography and endoscopic ultrasonography-guided fine-needle aspiration for the diagnosis and grading of pancreatic neuroendocrine tumors

Background and aim: Pancreatic neuroendocrine tumors (pNETs) are histologically categorized according to the WHO 2010 classification by their mitotic index or Ki-67 index as G1, G2, or G3. The present study examined the efficacy of endoscopic ultrasonography (EUS) and EUS-guided fine-needle aspiration (EUS-FNA) in the diagnosis and grading of pNET. Methods: We retrospectively reviewed 61 pNETs in 51 patients who underwent EUS between January 2007 and June 2014. All lesions were pathologically diagnosed by surgical resection or EUS-FNA. We evaluated the detection rates of EUS for pNET and sensitivity of EUS-FNA, and compared the Ki-67 index between EUS-FNA samples and surgical specimens. EUS findings were compared between G1 and G2/G3 tumors. Results: EUS showed significantly higher sensitivity (96.7%) for identifying pNET than CT (85.2%), MRI (70.2%), and ultrasonography (75.5%). The sensitivity of EUS-FNA for the diagnosis of pNET was 89.2%. The concordance rate of WHO classification between EUS-FNA and surgical specimens was 69.2% (9/13). The concordance rate was relatively high (87.5%, 5/6) in tumors <20 mm but lower (57.1%; 4/7) in tumors ≥20 mm. Regarding EUS findings, G2/G3 tumors were more likely to be large (>20 mm), heterogeneous, and have main pancreatic duct (MPD) obstruction than G1 tumors. Multivariate analysis showed large diameter and MPD obstruction were significantly associated with G2/G3 tumors. Conclusions: EUS and EUS-FNA are highly sensitive and accurate diagnostic methods for pNET. Characteristic EUS findings such as large tumor size and MPD obstruction are suggestive of G2/G3 tumors and would be helpful for grading pNETs.

Role of ERCP SpyGlass® Electrohydraulic Lithotripsy in Patients With Chronic Pancreatitis and Pancreatic Duct Calculi Causing Duct Obstruction: A Case Series

Introduction: ERCP with SpyGlass® cholangioscopy and electrohydraulic lithotripsy (EHL) is an established treatment for large common bile duct stones. However, the role of SpyGlass® EHL in treating patients with pancreatic duct calculi has yet to be well studied. The current management of pancreatic duct stones consists of extracorporeal shock wave lithotripsy (ESWL) or surgical intervention. The purpose of this case series is to study the safety and efficacy of SpyGlass® EHL in patients with pancreatic duct calculi. Methods: In patients with chronic pancreatitis and pancreatic duct stones, we performed ERCP with SpyGlass® pancreatoscopy and EHL in an attempt to break the calculi into smaller fragments in order to relieve the pancreatic duct obstruction. Consecutive patients with pancreatic duct stones were included in the study. Pancreatic duct stents were placed following lithotripsy in all patients. The stents were later removed at a 4-6 week interval after the procedure. Results: ERCP with SpyGlass® EHL was performed in 7 patients with chronic pancreatitis and stones. Two patients were relieved of their obstruction after only 1 procedure. Four patients required 2 procedures, and 1 patient required 3 procedures. ERCP with SpyGlass® EHL was successful in relieving the main pancreatic duct obstruction in 5 patients. The remaining 2 patients were referred to a multidisciplinary pancreas team for ESWL therapy. However, both these patients ended up requiring surgery. One patient received Puestow’s procedure while the other received Berger’s operation. Two patients had pain following the ERCP and EHL treatment and required overnight hospitalization. One patient had mild pancreatitis. No other complications were reported. Conclusion: ERCP with EHL appears to be a safe and effective therapeutic procedure in the majority of patients with chronic pancreatitis and pancreatic duct calculi. Larger studies are needed to validate the results of our pilot study.

主膵管途絶をきたした膵神経内分泌癌の1例

主膵管途絶をきたした膵神経内分泌癌の1例

Reconstruction after pancreatoduodenectomy: Pancreatojejunostomy vs pancreatogastrostomy.

Pancreatic surgeons try to find the best technique for reconstruction after pancreatoduodenectomy (PD) in order to decrease postoperative complications, mainly pancreatic fistulas (PF). In this work, we compare the two most frequent techniques of reconstruction after PD, pancreatojejunostomy (PJ) and pancreatogastrostomy (PG), in order to determine which of the two is better. A systematic review of the literature was performed, including major meta-analysis articles, clinical randomized trials, systematic reviews, and retrospective studies. A total of 64 articles were finally included. PJ and PG are usually responsible for most of the postoperative morbidity, mainly due to the onset of PF, being considered a major trigger of life-threatening complications such as intra-abdominal abscess and hemorrhagia. The included systematic reviews reported a significant difference only in the incidence of intraabdominal collections favouring PG. PF, delayed gastric emptying and mortality were not different. Although there was heterogeneity between these studies, all were conducted in specialized centers by highly experienced surgeons, and the surgical care was likely to be similar for all the studies. The disadvantages of PG include an increased incidence of delayed gastric emptying and of main pancreatic duct obstruction due to overgrowth by the gastric mucosa. Exocrine function appears to be worse after PG than after PJ, resulting in severe atrophic changes in the remnant pancreas. Depending on the type of PJ or PG used, the PF rate and other complications can also be different. The best method to deal with the pancreatic stump after PD remains questionable. The choice of method of pancreatic anastomosis could be based on individual experience and on the surgeon's preference and adherence to basic principles such as good exposure and visualization. In conclusion, up to now none of the techniques can be considered superior or be recommended as standard for reconstruction after PD.

Pancreatic Nonfunctioning Neuroendocrine Tumor With the Main Pancreatic Duct Obstruction Presenting as Excessive Hyperglycemia

We present the case of a 65-year-old man with a pancreatic nonfunctioning neuroendocrine tumor causing main pancreatic duct obstruction that presented as excessive hyperglycemia. We considered the tumor elicited worsening of diabetes in this case, and we performed review of the relevant literature.

Cleaning of occluded pancreatic duct endoprostheses: a new indication for extracorporeal shock wave lithotripsy?

Pancreatic duct stenting is widely performed for bridging main pancreatic duct obstruction in patients with chronic pancreatitis. The major limitation is early stent occlusion, making regular stent exchange necessary. To date, no measures are available to prevent stent occlusion. The aim of this study was to evaluate the cleansing effect of shock wave application (SWA) on occluded pancreatic duct stents in vitro. In vitro study. We analyzed occlusion rates of 25 plastic endoprostheses removed from 21 patients with chronic pancreatitis. We administered 350 shock wave pulses every 10 mm along the prosthesis, which was stored in a latex balloon filled with gas-free physiologic saline solution, by using a pressure of 42 megapascals. After SWA, the occlusion rate was measured again, and the cleansing rate was calculated in comparison with the native prosthesis. The mean (± SD) occlusion rate was significantly reduced (64.7 ± 28.7 [15%-100%]) before SWA vs 9.8 ± 25.3 [0-100%]) after SWA; P = .038). In 16 of 25 prostheses (64%), cleaning was complete. Four of the remaining 9 prostheses (16%) showed satisfactory cleaning of 95%, on average. Residual clogging material was found mainly at the duodenal tip and the middle of the stent. No significant association was found between patient-related or stent-related parameters and the cleansing effect of SWA. In vitro study design. SWA is effective in cleaning occluded pancreatic endoprostheses in vitro. Prolongation of stent placement seems possible if regular SWA is performed. Extracorporeal shock wave lithotripsy therefore might become a new indication for patients under treatment with pancreatic endoprostheses.

Endoscopic treatment in chronic pancreatitis, timing, duration and type of intervention

Endoscopic treatment of chronic pancreatitis (CP) aims to relieve pain by draining the main pancreatic duct (MPD) and to treat loco-regional complications. Half of patients have complete pain relief five years after treatment, with best results obtained if treatment is performed early after the first pain attack. If MPD obstruction is caused by calcifications, ambulatory extracorporeal shock wave lithotripsy has become a first-line treatment (9-30% of patients require ERCP during follow-up). If MPD obstruction is caused by stricture(s), insertion of single plastic stent is effective but it requires multiple ERCPs for stent exchanges; other protocols are being investigated. Pseudocysts represent an excellent indication for endoscopic treatment with long-term results similar to those of surgery; endosonography-guided techniques allow treatment of almost any pancreatic pseudocyst. Biliary strictures related to CP are challenging due to a high relapse rate and requirement for multiple ERCP sessions. Significant progress has recently been made with new protocols of temporary biliary stenting (multiple simultaneous plastic stents or covered metallic stents).

A case of small pancreatic acinar cell carcinoma detected by endoscopic ultrasonography (EUS)

A 53-year old man was first hospitalized to our hospital due to a severe abdominal pain on October 3, 2006. Acute pancreatitis possibly due to alcoholic drinking was diagnosed on an abdominal CT revealing the swollen pancreatic tail, peri-pancreatic fluid collection and pleural effusion. Magnetic resonance cholangio-pancreatography showed no abnormality of the main pancreatic duct (MPD). His hospital course was satisfactory and discharged 2weeks later, but he could not quit alcohol intake. He was second hospitalized due to acute pancreatitis on January 13, 2007, when CT showed slight dilatation of the MPD (3 mm) in the pancreatic body to tail without any space occupying lesions. After intermission of 6 months, he was third hospitalized due to the same reason, when CT showed ill-defined hypo-perfusion mass of 1cm at diameter with distal MPD dilatation suggesting MPD obstruction at the pancreatic body. Although radiologist interpreted this lesion as cystic dilatation of the pancreatic branch, we performed EUS to examine the reason of MPD obstruction. EUS defined a low echoic mass lesion of 10 mm at diameter slightly enhanced after the injection of the contrast material (Levovist). Intraductal ultrasonography (IDUS) for MPD showed an irregular low echoic mass adjacent to MPD. The result of endoscopical pancreatic biopsy was atypical cell proliferation showing glandular or solid pattern with high cellurality, suggesting acinar cell carcinoma. Distal pancreatectomy was performed on October 3, 2007. Small nodular lesion of 10×6 mm in the pancreatic body was histologically and immunohistochemically acinar cell carcinoma with slight venular/peineural and lymphatic permeations. There is no recurrence so far. We emphasize the importance of EUS and IDUS to identify small pancreatic tumor.