Palliative stents for malignant biliary obstruction – a meta-analysis

Aims: To perform a systematic review, and meta-analysis, of randomised clinical trials comparing endoscopic metal and plastic biliary stents for malignant biliary obstruction.

Methods: All abstracts containing pre-determined key words were screened, and those meeting selection criteria had the full study reviewed.

Results: Of 77 abstracts screened, 6 met inclusion criteria and 71 were excluded. In total 471 patients were randomised and 6 were lost to follow-up.

There were no significant differences with regard to technical success, therapeutic success, complications, survival or quality-of-life. There was a trend towards higher risk of 30-day mortality in the metal stent groups (RR 1.75, 95% CI 0.85–3.29). However metal stents had a significantly reduced relative risk of recurrent biliary obstruction prior to death (RR 0.52, 95% CI 0.39, 0.69), and rate of reintervention (WMD -0.67). These differences appear after 3 months in most studies. Two studies reported improved cost-effectiveness with metal stents, but two others did not (these were not suitable for meta-analysis).

Conclusions: Metal Wall stents have a reduced risk of biliary obstruction and need for reintervention when used to relieve malignant biliary obstruction. These benefits occur in patients surviving greater than three months after insertion. Their overall cost-effectiveness is unclear.