“…Fully or partially covered SEMSs were designed to overcome the tumor ingrowth occurring with uncovered SEMSs, but in retrospective cohort studies [13,17,18], randomized trials [8][9][10][11][12]15,16,19], and two meta-analyses [7,14], the clinical outcomes of covered SEMSs for stent patency were inconsistent due to the different proportions of stent migration, tumor ingrowth, tumor overgrowth, and bile encrustation in each of these studies. In addition, there have also been conflicting conclusions regarding the incidence of pancreatitis and cholecystitis after placement of various types of covered versus uncovered SEMSs [8][9][10][11][12][13][15][16][17][18][19][20][21][22][23].…”