Clinical Study On Endoscopic Ultrasound-guided Transmural Drainage Of Pancreatic Fluid Collections

Pancreatic fluid collections(PFC)is a common local complication of pancreas,which can occur secondary to acute/chronic pancreatitis,trauma or surgery.According to the 2012 revision of the Atlanta Classification,PFC can be generally classified into four categories based on their content and wall maturity,including acute peri-pancreatic fluid collection(APFC),acute necrotic collection(ANC),pancreatic pseudocysts(PPC),and walled-off pancreatic necrosis(WON).While most of PFC could resolve by itself,some exists for a long time and may cause signs or symptoms that need intervention.Traditional treatments techniques including percutaneous or surgical approaches.With the great advancement in endoscopic techniques,endoscopic ultrasonography(EUS)-guided transmural drainage has been gradually accepted as the first-line treatment for PFC,and it is thought to be effective and less invasive.The technology of operation is mature,while there are still some controversies on selection of stents.In addition,the creation of lumen-apposing metal stent(LAMS)is regarded as a revolutionary invention during the past 10 years and has triggered a worldwide trend of research.In this retrospective study,we aimed to summarize the experiences and evaluate its safety and efficacy of LAMS in PFC drainage.This study was also conducted to compare clinical efficacy and safety among plastic stent(PS),fully covered self-expanding metal stent(FCSEMS)and newly emerging LAMS.It may help to explore optimal strategies for endoscopic management of PFC.Part ? Endoscopic ultrasound-guided transmural drainage of pancreatic fluid collections with a novel lumen-apposing metal stent: Efficacy analysis and initial experienceObjective: To report the initial clinical application of a novel lumen-apposing metal stent(LAMS)in endoscopic ultrasound(EUS)-guided transmural drainage of pancreatic fluid collections(PFC)and evaluate its safety and efficacy.Methods: We performed a retrospective case series of 46 patients who underwent EUS-guided transmural drainage of PFC with placement of LAMS from September 2015 to April 2017.Clinical data were reviewed from the hospital records and follow-up data were obtained by telephone and outpatient contact.Result: A total of 49 LAMS was placed in 46 patients(including 3 patient with 2 LAMS placed for multiport access).The technical success was 95.9%(47/49),complications occurred in 14 patients(31.8%),including 2 severe complications(delayed hemorrhage and peritonitis).Additional intervention was required in 10 patients(22.7%).The mean hospital stay was 6.0 ± 6.6 days and patients were followed for a mean of 18.4 ± 5.2 months.Treatment success was achieved in 40 patients(90.9%).Stent removal was performed after a mean of 59.4 ± 28.0 days after the initial procedure.Besides,recurrence rate observed was 10% during the follow-up periodConclusion: Drainage of PFC using special designed LAMS is effective and relatively safe.More clinical application experience is needed to reduce stent-related complications.Part ? Comparison of three different stents for endoscopic ultrasound-guided drainage of pancreatic fluid collectionObjective: Endoscopic transmural drainage has been recognized as the first-line treatment for pancreatic fluid collection(PFC).Currently,three different types of stents have been extensively applied,including double pigtail plastic stent(DPPS),fully covered self-expanding metal stent(FCSEMS)and novel lumen-apposing metal stent(LAMS).Nonetheless,limited data are available about the comparison among them in terms of their clinical outcomes and safety for endoscopic ultrasound(EUS)-guided drainage of PFC.Methods: The current retrospective study was carried on 160 PFC patients undergoing EUS-guided drainage from 2010 to 2018 at a single tertiary care center.Patients were divided into 3 groups based on different drainage ways: drainage using PS,FCSEMS or LAMS.The primary outcomes were the rates of clinical success and adverse events,while the secondary outcomes included technical success,length of hospital stay,re-intervention,6-months recurrence and stent removal.Results: A total of 160 PFC patients(104 male,56 female)were analyzed in this retrospective study,including 62 patients drained with DPPS,28 with FCSEMS and 70 with LAMS.Typically,the technical success(93.5% vs 96.4% vs 94.3%,P=1.000)and treatment success rates(84.6%vs 85.2% vs 89.2%,P=0.763)were similar between DPPS,FCSEMS and LAMS.Meanwhile,no statistically significant differences were observed in length of hospital stay(7.8 vs 7.0 vs 6.5,P=0.646),re-intervention(13.5% vs 25.9% vs 27.7%,P=0.161),recurrence(13.6% vs 21.7% vs 8.6%,P=0.236)and major adverse events(AEs)(15 vs 11 vs 16,P=0.289)among them.However,the mean time of stent removal was markedly longer in patients drained with DPPS than LAMS and FCSEMS group(94.0d vs 58.0d vs 60.5d,P=0.000).With regard to major AEs,11 patients(FCSEMS: n=3,and LAMS: n=4,DPPS=4)developed severe bleeding,among them,2 patients in LAMS group died of non-response to radiology-guided coil embolization and/or surgery.Conclusions: There are no significant differences in the clinical outcomes of PFC patients treated with DPPS,FCSEMS or LAMS.Nonetheless,efficacy of LAMS might not be substantially improved and severe(or even fatal)bleeding may occur at the early stage after metal stent placement,which should be paid particular attention to.Safety of LAMS need further exploration.