Latest Perspective of ERCP

Latest Perspective of ERCP

--- Stent Treatment for Benign Biliary Stricture

Publicized in J ClinHepatol Vol.34 No. 3, Mar. 2018.

Presently the widely used treatment of benign biliary stricture is plastic stent implantation. The operational principle is more than one time stent implantation with more than one plastic stent.

Stent is expanding the stricture and the treatment process takes one year.

In recent year, the covered metal stent have been widely used for benign stricture with its advantages of easy placement, easy removal and strong expanding force.

A recent multicenter research compared the treatment effect of the fully covered metal stent and plastic stent in treating benign biliary stricture.

112 patients were compared in this research. The benign biliary obstruction strictures in these cases are caused by hepatic transplantation, chronic pancreatitis, and operational injury.

These patients are divided into two groups for the treatment by metal stent and plastic stent respectively.  

The results compare the performance of metal stent and plastic stent in these aspects and we could see that metal stents outperformed plastic stents in most aspects evaluated.

We see from the comparison experiment, the advantages of covered metal stents in treating benign stricture are reflected in reducing ERCP operation times, lowering the cost and shortening treatment duration time.  The rate of obstruction alleviation, reoccurrence rate and complication rate do not have obvious difference. Reoccurrence of stricture and covered stent migration happen mostly in hepatic transplantation strictures.

The time to retrieve the stents do not have fixed conclusion till now. According to the report, it is 3-6 months. Long-term stent implantation may cause biliary stricture and injury.

The main concern of the covered metal stent in treating benign obstruction is stent migration in early curative period. The novel stent shape with wings or the design to achieve different radial force in different segment would be the solution for stent migration.

--- How to extend stent patency term in malignant obstruction  

Radiofrequency ablation, as assisted method to reduce tumor growth and extend stent patency term for the malignant obstruction loosing open surgery opportunities, is proved safe and feasible in prospective and retrospective researches. It could be used in malignant obstruction with whatever causes.

In the research, it shows that after one to two times RFA, the inner diameter of stricture became larger by 2mm to 5 mm. In the retrospective experiment, pure RFA treatment, comparing with pure 10Fr plastic stent implantation, it has remarkably longer patency term( 156 days士122days) VS (65. 3days士40 days, P =0.016) . The stent patency rate in 90 days implantation is much better in RFA treatment group(64 % vs 24 % , P = 0 . 03 ).

Another research involving 505 patients indicates that stent implantation combining with RFA could effectively extend the patency term with around 51 days and extend the life time of patients by 285days. The experiment cases chosenin the randomexperiment are not able to provide sufficient evidence of optimal RFA parameter, RFA treatment interval and treatment times, the common sense of RFA combined stent treatment in malignant biliary obstruction have not been reached yet.