Evaluate the Efficacy of Adding Intraluminal Brachytherapy After CCRT for Local-regional Thoracic Esophageal Cancer.

The device is intended for use with a commercially available after loader during brachytherapy. The purpose of the device is to deliver a radioactive source to the esophagus. This device is sterile, disposable, and single-use.

Brachytherapy protocol starts within 12 weeks after EBRT. High-dose-rate (HDR) 5-Gy per fraction is delivered to GTV of esophageal tumor(s), second fraction (if applicable) to be done within 2 weeks after the first fraction, for a total of 5-10Gy in 1-2 fractions will be delivered.