The effectiveness and prognostic factors of radioactive iodine-125 seed implantation for the treatment of cervical lymph node recurrence of esophageal squamous cell carcinoma after external beam radiation therapy - Zhang, Yuwei; Liu, Zezhou; Liang, Yansong; Chen, Enli; Zhang, Hongtao; Gao, Zhen; Wang, Juan (Journal of Contemporary Brachytherapy, 2020)