title: Transpapillary microwave coagulation therapy for recanalizing self-expandable metallic stents occluded by tumor ingrowth: initial experience.
abstract: Percutaneous microwave coagulation for recanalizing stents occluded by tumor ingrowth has been reported. With this technique, however, the percutaneous drain diminishes the quality of life in patients with unresectable tumors and a limited prognosis. Transpapillary microwave ablation was attempted in three patients with occluded stents. After a sheath had been inserted into the proximal hepatic duct across the occluded region, a microwave electrode was introduced into the intrahepatic duct via the sheath. We used microwave therapy with an output power of 40 W, based on our previous in vitro study. Except in one patient, the stents were successfully recanalized with one or two attempts. In one patient who underwent ablation in the intrahepatic duct, a 1.8-mm electrode enabled recanalization of the stent. In another who underwent ablation in the extrahepatic duct, however, a larger electrode was required. There were no procedure-related complications. Transpapillary microwave coagulation of occluded stents appears to be an alternative to percutaneous microwave coagulation with an electrode fitting the stent size. The technique might be easier with the use of a redesigned electrode with a guide wire lumen.
authors.affiliation: Third Dept. of Internal Medicine, Toho University School of Medicine, Ohashi Hospital, 2-17-6 Ohashi Meguro-ku, Tokyo 153-8515, Japan. maet@oha.toho-u.ac.jp
authors.forename: I
authors.initials: I
authors.lastname: Maetani
authors.forename: T
authors.initials: T
authors.lastname: Ukita
authors.forename: H
authors.initials: H
authors.lastname: Inoue
authors.forename: Y
authors.initials: Y
authors.lastname: Igarashi
authors.forename: H
authors.initials: H
authors.lastname: Hoshi
authors.forename: Y
authors.initials: Y
authors.lastname: Sakai
mesh_terms: D000368:Aged; D001650:Bile Duct Neoplasms / Q000150:complications / Q000473:pathology / Q000601:surgery*; D004564:Electrocoagulation / Q000379:methods*; D016099:Endoscopy, Gastrointestinal; D005260:Female; D005706:Gallbladder Neoplasms / Q000150:complications / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008872:Microwaves / Q000627:therapeutic use*; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000628:therapy*; D010166:Palliative Care / Q000379:methods*; D011788:Quality of Life; D015607:Stents / Q000009:adverse effects; D016896:Treatment Outcome