Technical evaluation of intraluminal brachytherapy in the esophagus and biliary tract using selectron high dose rate remote afterloading unit

　　With the advent of sophisticated remote afterloading unit and computer treatment planning system, a great advance is made in the field of radiotherapy for cancer treatment. Brachytherapy, literally meaning short distance treatment,allows local eradication of tumor cells with diminishing risk of damage to the adjacent normal tissues. Radioactive sources may reach or be embedded in the tumor site in various ways; via intraluminal, endocavitary or interstitial applications, or by direct contact. We have successfully treated two inoperable patients, one of esophageal cancer and the other of distal common bile duct tumor, with brachytherapy with or without the combination of external irradiation. The brachytherapy was performed via intraluminal route using the available Selectron high-dose rate remote afterloading　unit and its accessory, the Selectron Rowland esophageal　applicator. This applicator has a large diameter and a rather rigid solid tip, this causes some problems in the applications, thus is difficult to be inserted down the throat without the guidance of endoscope in the case of esophageal cancer. In the case of distal common bile duct cancer, the tract of percutaneous biliary drainage must be dilated several times to allow the passage of the applicator. Despite of these shortcomings, tumor control was effective. Followup imagings and clinical study shortly after the treatment showed dramatic diminution of the tumor. Patients also tolerated the treatment well.#1397#