Endoscopic retrograde cholangiopancreatography drainage for palliation of malignant hilar biliary obstruction——stent-in-stent or side-by-side?A systematic review and meta-analysis

BACKGROUND Biliary drainage,either by the stent-in-stent(SIS)or side-by-side(SBS)technique,is often required when treating a malignant hilar biliary obstruction(MHBO).Both methods differ from each other and have distinct advantages.AIM To compare both techniques regarding their efficacy and safety in achieving drainage of MHBO.METHODS A comprehensive search of multiple electronic databases(MEDLINE,Embase,LILACS,BIREME,Cochrane)was conducted and grey literature from their inception until December 2020 with no restrictions regarding the year of publication or language,since there was at least an abstract in English.The included studies compared SIS and SBS techniques through endoscopic retrograde cholangiopancreatography.Outcomes analyzed included technical and clinical success,early and late adverse events(AEs),stent patency,reintervention,and procedure-related mortality.RESULTS Four cohort studies and one randomized controlled trial evaluating a total of 250 patients(127 in the SIS group and 123 in the SBS group)were included in this study.There were no statistically significant differences between the two groups concerning the evaluated outcomes,except for stent patency,which was higher in the SIS compared with the SBS technique[mean difference(d)=33.31;95%confidence interval:9.73 to 56.90,I2=45%,P=0.006].CONCLUSION The SIS method showed superior stent patency when compared to SBS for achieving bilateral drainage in MHBO.Both techniques are equivalent in terms of technical success,clinical success,rates of both early and late AEs,reintervention,and procedure-related mortality.

Biliary drainage in inoperable malignant biliary distal obstruction: A systematic review and meta-analysis

BACKGROUND Endoscopic drainage remains the treatment of choice for unresectable or inoperable malignant distal biliary obstruction(MDBO).AIM To compare the safety and efficacy of plastic stent(PS)vs self-expanding metal stent(SEMS)placement for treatment of MDBO.METHODS This meta-analysis was developed according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.A comprehensive search was performed in MEDLINE,Cochrane,Embase,Latin American and Caribbean Health Sciences Literature,and grey literature to identify randomized clinical trials(RCTs)comparing clinical success,adverse events,stent dysfunction rate,reintervention rate,duration of stent patency,and mean survival.Risk difference(RD)and mean difference(MD)were calculated and heterogeneity was assessed with I2 statistic.Subgroup analyses were performed by SEMS type.RESULTS Twelve RCTs were included in this study,totaling 1005 patients.There was no difference in clinical success(RD=-0.03,95%confidence interval[CI]:-0.01,0.07;I 2=0%),rate of adverse events(RD=-0.03,95%CI:-0.10,0.03;I2=57%),and mean patient survival(MD=-0.63,95%CI:-18.07,19.33;I2=54%)between SEMS vs PS placement.However,SEMS placement was associated with a lower rate of reintervention(RD=-0.34,95%CI:-0.46,-0.22;I2=57%)and longer duration of stent patency(MD=125.77 d,95%CI:77.5,174.01).Subgroup analyses revealed both covered and uncovered SEMS improved stent patency compared to PS(RD=152.25,95%CI:37.42,267.07;I2=98%and RD=101.5,95%CI:38.91,164.09;I2=98%;respectively).Stent dysfunction was higher in the covered SEMS group(RD=-0.21,95%CI:-0.32,-0.1;I²=205%),with no difference in the uncovered SEMS group(RD=-0.08,95%CI:-0.56,0.39;I²=87%).CONCLUSION While both stent types possessed a similar clinical success rate,complication rate,and patient-associated mean survival for treatment of MDBO,SEMS were associated with a longer duration of stent patency compared to PS.