Advancements in the endoscopic treatment of pancreatic fluid collections

Pancreatic pseudocyst: The past, the present, and the future

A pancreatic pseudocyst is defined as an encapsulated fluid collection with a well-defined inflammatory wall with minimal or no necrosis. The diagnosis cannot be made prior to 4 wk after the onset of pancreatitis. The clinical presentation is often nonspecific, with abdominal pain being the most common symptom. If a diagnosis is suspected, contrast-enhanced computed tomography and/or magnetic resonance imaging are performed to confirm the diagnosis and assess the characteristics of the pseudocyst. Endoscopic ultrasound with cyst fluid analysis can be performed in cases of diagnostic uncertainty. Pseudocyst of the pancreas can lead to complications such as hemorrhage, infection, and rupture. The management of pancreatic pseudocysts depends on the presence of symptoms and the development of complications, such as biliary or gastric outlet obstruction. Management options include endoscopic or surgical drainage. The aim of this review was to summarize the current literature on pancreatic pseudocysts and discuss the evolution of the definitions, diagnosis, and management of this condition.

Lumen-apposing metal stents versus traditional self-expanding metal stents for endoscopic ultrasound-guided drainage of pancreatic fluid collections: a systematic review and meta-analysis

BACKGROUND

Endoscopic drainage has become the preferred treatment for pancreatic fluid collections (PFCs). There is still a lack of reliable evidence to prove which metal stent is the best choice for endoscopic ultrasound (EUS)-guided drainage of PFCs. In this study, we aimed to evaluate the efficacy and safety of lumen-apposing metal stents (LAMS) compared to traditional self-expanding metal stents (SEMS) in meta-analysis.

METHODS

We systematically searched PubMed, Embase, Web of Science, and Cochrane Library up to July 15, 2023. Relevant publications that compared LAMS with traditional SEMS for drainage of patients' PFCs under EUS-guidance were included. This meta-analysis assessed endpoints using Review Manager 5.3 and Stata 14.0 statistical software.

RESULT

Nine citations comprising 707 patients with PFCs were included. The clinical success rate of LAMS tended to be higher than that of SEMS (RR = 1.07, 95%CI [1.00, 1.15], P = 0.05). LAMS had a lower technical success rate (RR = 0.97, 95%CI [0.94, 0.99], P = 0.02) and faster procedure time (minutes) (MD =  - 24.29, 95%CI [- 25.59, - 22.99], P < 0.00001) compared to SEMS. In addition, LAMS had fewer overall adverse events (RR = 0.64, 95%CI [0.48, 0.87], P = 0.004). For specific adverse events, LAMS had fewer migration (RR = 0.37, 95%CI [0.19, 0.72], P = 0.003), occlusion (RR = 0.43, 95%CI [0.22, 0.82], P = 0.01) and infection (RR = 0.38, 95%CI [0.20, 0.70], P = 0.002). There was no significant difference in bleeding and perforation between the two stents. For hospital stay (days), LAMS group was similar to SEMS group (MD =  - 3.34, 95%CI [- 7.71, - 1.03], P = 0.13). Regarding recurrence, LAMS group was fewer than SEMS group (RR = 0.41, 95%CI [0.21, 0.78], P = 0.007).

CONCLUSION

Compared to traditional SEMS, LAMS has a higher clinical success rate, faster procedure time, fewer adverse events, similar hospital stay and lower recurrence rate in EUS-guided drainage of PFCs. LAMS is a good choice with a high technical success rate over 95%, and using a shorter length or "one-step" operation can further improve it. Richer placement experience is required for LAMS placement under EUS-guidance.

Comparative outcomes of endoscopic ultrasound-guided lumen-apposing mental stents drainage for pancreatic pseudocysts and walled-off necrosis: Case series and meta-analysis

Background

Endoscopic ultrasound (EUS)-guided transmural drainage for pancreatic fluid collections (PFCs) has become the first-line treatment with quicker recovery and more minor injury compared with surgery and percutaneous drainage. The efficacy of stents implantation and drainage for different PFCs remains controversial, especially lumen-apposing metal stents (LAMS). This study aimed to compare the efficacy and safety of LAMS drainage for pancreatic pseudocysts (PPC) and walled-off necrosis (WON).

Methods

A meta-analysis was performed for LAMS drainage for WON and PPC by systematically searching PubMed, Cochrane, and Embase databases from January 2010 to January 2020. From 2017 to 2019, 12 patients who were treated with LAMS drainage for PFCs in our medical center were also reviewed and included in this study.

Results

Combining 11 copies of documents with the data from our medical center, a total of 585 patients with PFCs were enrolled in this meta-analysis, including 343 patients with WON and 242 with PPC. The technical success rate in WON is not significantly different from that of PPC (P = 0.08 > 0.05). The clinical success of LAMS placement was achieved in 99% vs 89% in PPC and WON, respectively (RR = 0.92, 95% CI: 0.86-0.98, P = 0.01 < 0.05). The further intervention of direct endoscopic necrosectomy was required by 60% of patients in WON group. There was no significant difference in the incidence of adverse events, including infection, bleeding, stent migration and stent occlusion, after LAMS placement between WON and PPC.

Conclusions

Endoscopic ultrasound-guided LAMS for PFCs are feasible, effective with preferable technical and clinical success rates. The clinical effect of LAMS on PPC is slightly better than that of WON, but its adverse reactions still need to be verified in a large-sample prospective study.

Endoscopic Management of Pancreatic Fluid Collections

Pancreatic fluid collections (PFCs) are a common sequela of pancreatitis. Most PFCs can be managed conservatively, but symptomatic PFCs require either surgical, percutaneous, or endoscopic intervention. Recent advances in the therapeutics of PFCs, including the step-up approach, endoscopic ultrasound-guided transmural drainage with lumen apposing metal stents, and direct endoscopic necrosectomy, have ushered endoscopy to the forefront of PFCs management and have allowed for improved patient outcomes and decreased morbidity. In this review, we explore the progress and future of endoscopic management of PFCs.