Which stent to use for the management of pancreatic pseudocysts? Time for randomized controlled studies

We read the paper by Yang et al. [1] that presented the results of a large, retrospective, multicenter study comparing lumen-apposing metal stents (LAMSs) versus double-pigtail plastic stents (DPPSs) for the management of pancreatic pseudocysts. Among 205 patients (LAMS, 80; DPPS, 125), use of LAMSs was associated with significantly better clinical success, and lower rates of adverse events and placement of percutaneous drainage [1].

Some considerations that could have affected the results of this study need to be made. A mean (standard deviation) of 1.9 (0.57) DPPSs were inserted, which denotes that in certain cases a single DPPS was used. It would be interesting to know the number of these cases, the size of the stent, the clinical outcome of the procedure (how many of the 11 infections in the DPPS arm occurred in these patients), and if taking out these patients from the analysis would change the results. It is also important to know if the increased requirement for percutaneous drainage in the DPPS group was related to the more frequent paracolic gutter extension.

A higher rate of severe bleeds was observed in the DPPS group versus the LAMS group, which is different to what is reported in patients with walled-off necrosis (WON) [2] [3]. While various meta-analyses have shown better clinical outcomes and less adverse events in WON patients treated with LAMSs, the only available randomized controlled study described no differences in the clinical outcomes between LAMSs and DPPSs, but a significantly higher rate of severe stent-related adverse events in the LAMS arm [5].

A lesson has to be learnt from the above experience with WON, where the results of retrospective studies and meta-analyses were completely overturned by properly designed studies. This would seem to pave the road to finally answering the unresolved question of which type of stent should be used in patients with pancreatic pseudocysts.

Publication History

Article published online:
25 March 2020

• References

• 1 Yang J, Chen YI, Friedland S. et al. Lumen-apposing stents versus plastic stents in the management of pancreatic pseudocysts: a large, comparative, international, multicenter study. Endoscopy 2019; 51: 1035-1043
• 2 Lang GD, Fritz C, Bhat T. et al. EUS-guided drainage of peripancreatic fluid collections with lumen-apposing metal stents and plastic double-pigtail stents: comparison of efficacy and adverse event rates. Gastrointest Endosc 2018; 87: 150-157
• 3 Brimhall B, Han S, Tatman PD. et al. Increased incidence of pseudoaneurysm bleeding with lumen-apposing metal stents compared to double-pigtail plastic stents in patients with peripancreatic fluid collections. Clin Gastroenterol Hepatol 2018; 16: 1521-1528
• 4 Hammad T, Khan MA, Alastal Y. et al. Efficacy and safety of lumen-apposing metal stents in management of pancreatic fluid collections: Are they better than plastic stents? A systematic review and meta-analysis. Dig Dis Sci 2018; 63: 289-301
• 5 Bang JY, Hasan M, Navaneethan U. et al. Lumen-apposing metal stents (LAMS) for pancreatic fluid collection (PFC) drainage: may not be business as usual. Gut 2017; 66: 2054-2056