Postoperative fluid collections: a new indication for interventional endoscopic ultrasound?

We read with interest the study by Yang J et al. [1] and congratulate the authors for their innovative works. This retrospective, international, multicenter study showed lumen-apposing metal stents (LAMS) to be a feasible alternative in the management of postoperative fluid collections (POFCs), with good safety and efficacy. This finding will facilitate expanding indications for interventional EUS. We sincerely appreciate the authors sharing their experience, and offer some points requiring clarification.

The definition of clinical success excludes patients with a need for percutaneous drainage, which may introduce bias. Clinically, EUS-guided LAMS drainage is often used in patients with insufficient percutaneous drainage. The large diameter of LAMS is an advantage, as percutaneous drains are often retained for lavage and drainage. In the study, repeated endoscopic procedures and multiple LAMS were permitted to achieve clinical success, whereas additional percutaneous drainage was considered as treatment failure, which is confusing.

According to the International Study Group of Pancreatic Fistula, 56.5 % (35 /62) of POFCs should be attributed to postoperative pancreatic fistula (POPF, Grade B) [2]. Mudireddy et al. [3] reported a similar study, with all 26 pancreatic POFCs resulting from pancreatic duct leaks. In the present study, however, only 12 of 35 pancreatic POFCs were diagnosed with leaks. To promote communication with surgery, it would be better to provide criteria of pancreatic leak and any differences from the universally accepted POPF system.

LAMSs bridge the space between medicine and surgery, but the average number of cases for each center (62 cases, 19 centers) is small. This situation also occurs in China, partly due to insufficient multidisciplinary collaboration. We believe that given the similarity of POFCs and pancreatic pseudocysts, EUS-guided LAMS therapy will be the first-line treatment for POFCs after pancreatectomy [4]. However, for POFCs of other etiologies, we still have a long way to go.

• References

• 1 Yang J, Kaplan JH, Sethi A. et al. Safety and efficacy of the use of lumen-apposing metal stents in the management of postoperative fluid collections: a large, international, multicenter study. Endoscopy 2019; 51: 715-721
• 2 Bassi C, Marchegiani G, Dervenis C. et al. The 2016 update of the International Study Group (ISGPS) definition and grading of postoperative pancreatic fistula: 11 years after. Surgery 2017; 161: 584-591
• 3 Mudireddy PR, Sethi A, Siddiqui AA. et al. EUS-guided drainage of postsurgical fluid collections using lumen-apposing metal stents: a multicenter study. Gastrointest Endosc 2018; 87: 1256-1262
• 4 Diehl DL. Therapeutic endoscopic ultrasound for postoperative fluid collections: a surgeon’s best friend. Endoscopy 2019; 51: 711-712