A commentary on ‘Does pancreatic duct stent placement lead to decreased postoperative pancreatic fistula rates after pancreaticoduodenectomy? A meta-analysis’

Dear Editor,

Pancreaticoduodenectomy (PD) is the standard resection for various benign and malignant diseases of the periampullary region. It is a complex surgical procedure historically associated with high operative mortality rates, although technical advances and centralization of care have improved the safety of PD significantly in many institutions around the world. In our institution’s experience, the most common complications following PD in descending order of frequency are delayed gastric emptying, pancreatic fistula, and wound infection¹. These complications, particularly the first two, can have a profound impact on the patient’s physical and emotional well-being.

Surgeons have attempted to identify risk factors for pancreatic fistulas with the hope of devising effective strategies to reduce the leak rate. The placement of a stent across the pancreaticojejunostomy anastomosis is an attractive strategy to reduce the pancreatic fistula rate following PD. Several published reports advocate this technique, but these studies are uncontrolled retrospective studies or prospective studies that do not compare their results to an appropriate control group without a pancreatic duct stent. Guo et al.² performed a meta-analysis of randomized controlled trials to evaluate the effectiveness of pancreatic duct stent placement for preventing postoperative pancreatic fistula after PD. They concluded that pancreatic duct stents did not reduce the risk of postoperative pancreatic fistula compared with no stents. External stents were associated with a reduced postoperative pancreatic fistula rate compared with no stents.

An external stent diverts pancreatic juice away from the pancreaticojejunal anastomosis, preventing the activation of pancreatic enzymes by bile that may lead to an anastomotic breakdown. Internal stents may provide limited protection of the pancreaticojejunal anastomosis against these activated enzymes. External stents provide improved local control of secretions if an anastomotic leak occurs and may decompress the denervated jejunal segment better than internal stents. In addition, an external stent could decrease the chance of stent migration compared with the use of a short internal stent³. Proximal migration of internal pancreatic duct stent has been reported and could reach about 5% after endoscopic placement.

Obesity was found to be associated with the development of postoperative pancreatic fistula by multivariable analysis⁴. Although there might not have been enough cases of postoperative pancreatic fistula in the present study for the evaluation of multiple factors, several reports have examined relationships between obesity and complications after PD. Obesity may affect both the texture of the pancreatic remnant and the quality of the pancreatic anastomosis. The impact of obesity on the technical difficulty of many abdominal procedures has been reported to translate into longer operating times and increased blood loss⁵.

The results of this meta-analysis should be interpreted with caution for a number of reasons: (1) incomplete reporting of crucial design issues may impair the assessment of trial quality; (2) the blinded statuses of participants and outcome assessors were not described in any trials, and this likely created a significant source of variation in effect estimates between studies; (3) clinical factors such as experience of the operating surgeons and perioperative management of the patients may have inordinately influenced the results of this systematic analysis; (4) there have also been reports of laparoscopic PD and robot-assisted PD techniques, which may be associated with different incidences of pancreatic fistula, therefore, subgroup analysis was necessary. Future prospective randomized trials to study innovative approaches to prevent pancreatic fistulas remain a high priority for pancreatic surgeons.

Ethical approval

Not applicable.

Sources of funding

Not applicable.

Author contribution

C.T.: drafted this manuscript; G.C. and W.F.: suggested comment points. All authors had seen and approved the final manuscript.

Conflicts of interest disclosure

There are no conflicts of interest.

Research registration unique identifying number (UIN)

As this paper is a letter to the editor regarding commentary on the original article published in International Journal of Surgery, research registration is unnecessary.

Guarantor

Wenming Feng.