P.03.19 ENDOSCOPIC BILIARY SPHINCTEROTOMY IN MALIGNANT BILIARY OBSTRUCTION IN CASE OF STENT PLACEMENT: A SYSTEMATIC REVIEW WITH META-ANALYSIS. Issue 2 (15th March 2018) - Mangiavillano, B.; Bianchetti, M.; Montale, A.; Frazzoni, L.; Repici, A.; Fuccio, L.