Experience with the new multi-hole self-expandable metallic stent

Multi-hole self-expandable metallic stent (M.I.Tech/Boston Scientific: MHSEMS) has small holes in the cover part of FCSEMS and has properties between UCSEMS and FCSEMS. The MHSEMS was originally an FCSEMS with holes in all cells. In the distal bile duct, the MHSEMS have the potential to prevent migration by allowing tissue to enter the small holes. In the hilar region, the MHSEMS can potentially prolong the duration of patency of the central bile duct by preventing ingrowth by covering the branches without impeding them. However, because there were reports of cases of inoperable removal due to ingrowth overseas, the model launched in Japan in 2022 had fewer holes, and the cover of the Hanarostent Biliary Full Cover NEO (M.I. Tech/Boston Scientific) had a row of holes in every other row. It was used in 7 cases of malignant biliary obstruction. The primary diseases were gallbladder cancer, cholangiocarcinoma, and pancreatic cancer. The obstruction sites were the hilar region and the distal bile duct. All patients underwent successful implantation with no pancreatitis or cholangitis observed. Five patients continued chemotherapy. One gallbladder cancer patient died after 20 days, one cholangiocarcinoma patient experienced obstruction after 81 days, and the other five cases showed no evidence of obstruction or deviation (ranging from 6 to 119 days after implantation, with an average of 75 days). MHSEMS can be used for malignant biliary obstruction, mainly in the distal bile duct.