Protocol of early lumen apposing metal stent removal for pseudocysts and walled off necrosis avoids bleeding complications

Background: EUS-guided drainage of pancreatic fluid collections (PFCs; pancreatic pseudocyst (PPC) or walled-off necrosis (WON)) using lumen apposing metal stents (LAMSs) is now standard of care. We adopted a protocol of early LAMS removal and prospectively followed patients to determine if this protocol avoids bleeding complications.Methods: Prospective, consecutive case series of all patients with PPC and WON who underwent drainage with LAMS at a tertiary care referral center from July 2016 to November 2018. LAMS was removed within 4 weeks for PPC and within 6 weeks for WON. Patients with residual necrosis after 6 weeks underwent removal of initial LAMS and replacement with new LAMS every 6 weeks until resolution. Patients were followed within protocol while monitoring for bleeding complications and clinical success. We also performed a literature review to determine rates of LAMS related bleeding at various timepoints.Results: Forty patients (PPC n = 19, WON n = 21) underwent drainage with LAMS. Median time for LAMS removal was 21.0 days for PPC and 33.5 days for WON. Technical success and clinical success were achieved in 40/40 patients with zero cases of delayed bleeding. A literature review of 21 studies and 1378 patients showed 52/1378 (3.8%) bleeding events with 24/52 (46.2%) events occurring within 1 week of LAMS placement.Conclusions: An early removal LAMS protocol for PFC is highly efficacious and prevents delayed bleeding. Based on analysis of published cases, half of LAMS related bleeding occurs within the first week suggesting procedural factors rather than stent dwell time impact risk of bleeding.

Pancreatic cysts suspected to be branch duct intraductal papillary mucinous neoplasm without concerning features have low risk for development of pancreatic cancer

BACKGROUND

The risk of developing pancreatic cancer is uncertain in patients with clinically suspected branch duct intraductal papillary mucinous neoplasm (BD-IPMN) based on the "high-risk stigmata" or "worrisome features" criteria proposed in the 2012 international consensus guidelines ("Fukuoka criteria").

METHODS

Retrospective case series involving patients referred for endoscopic ultrasound (EUS) of indeterminate pancreatic cysts with clinical and EUS features consistent with BD-IPMN. Rates of pancreatic cancer occurring at any location in the pancreas were compared between groups of patients with one or more Fukuoka criteria ("Highest-Risk Group", HRG) and those without these criteria ("Lowest-Risk Group", LRG).

RESULTS

After exclusions, 661 patients comprised the final cohort (250 HRG and 411 LRG patients), 62% female with an average age of 67 years and 4 years of follow up. Pancreatic cancer, primarily adenocarcinoma, occurred in 60 patients (59 HRG, 1 LRG). Prevalent cancers diagnosed during EUS, immediate surgery, or first year of follow up were found in 48/661 (7.3%) of cohort and exclusively in HRG (33/77, 42.3%). Using Kaplan-Meier method, the cumulative incidence of cancer at 7 years was 28% in HRG and 1.2% in LRG patients (P<0.001).

CONCLUSIONS

This study supports using Fukuoka criteria to stratify the immediate and long-term risks of pancreatic cancer in presumptive BD-IPMN. The risk of pancreatic cancer was highest during the first year and occurred exclusively in those with "high-risk stigmata" or "worrisome features" criteria. After the first year all BD-IPMN continued to have a low but persistent cancer risk.