A Geant4 study on dosimetric comparison between three kinds of radioactive esophageal stents to be used in treatment of advanced esophageal cancers

‎Utilizing radioactive stents is a usual method for treatment of advanced esophageal cancer‎. ‎It is necessary to investigate the dose distribution of radioactive esophageal stents before the clinical use‎. ‎This study presents a dosimetric comparison between three radioactive esophageal stents‎: ‎I-125 seed-loaded stent‎, ‎iodine-eluting stent and double-layered iodine-eluting stent‎. ‎Depth-dose and angular dose distributions were carried out using Geant4 toolkit‎. ‎Moreover‎, ‎the effect of interval distance between two adjacent seeds on the dose distribution was investigated‎. ‎Esophageal stents loaded with I-125 seeds seems to be better than iodine-eluting stents‎, ‎with the distance less than 15 mm between two adjacent seeds‎.