Endobronchial Ultrasound-Guided Iodine-125 Radioactive Seed Implantation as a Novel Therapy for Mediastinal Tumors

This study aims to test the treatment effect of endobronchial ultrasound (EBUS)-guided interstitial iodine-125 (¹²⁵I) seed implantation for mediastinal lymph node metastasis or advanced mediastinal lung cancer. The patients with mediastinal lymph node metastasis or advanced mediastinal lung cancer, who had undergone surgery for resection of primary lesions and repeated chemotherapy or external radiotherapy, were selected and scheduled to undergo EBUS-guided ¹²⁵I seed implantation from December 2015 to May 2017. Forty patients were included into this study. Clinical data of these patients were collected and the short-term effects were observed. Then, the feasibility for treating mediastinal tumors was retrospectively analyzed. The follow-up period ranged within 1-6 months. The procedure was successfully completed, and all patients well tolerated the procedure without any major complications. The response evaluation criteria in solid tumors were utilized to test the treatment effect, and the overall response rates (complete remission + partial remission) at postoperative 2, 4, and 6 months were 65.00% (13/20), 80.00% (16/20), and 85.0% (17/20), respectively. All patients of this study survived throughout the follow-up period. This experience revealed that EBUS-guided ¹²⁵I radioactive seed implantation is effective and safe, and is a prospective approach for treating patients with mediastinal lymph node metastasis or advanced mediastinal lung cancer.