[Clinical efficacy and safety analysis of 125I seed implantation in the treatment of mediastinal lymph node metastasis of lung cancer].

Objective: To investigate the clinical efficacy and safety of 125I seed implantation in the treatment of mediastinal lymph node metastasis of lung cancer. Methods: Clinical data of 36 patients who underwent CT-guided 125I seed implantation for mediastinal lymph node metastasis of lung cancer from August 2013 to April 2020 in three hospitals of the Northern radioactive particle implantation treatment collaboration group were retrospectively collected, including 24 males and 12 females, aged 46 to 84 years. Cox regression model was used to analyze the relationship between local control rate, survival rate and tumor stage, pathological type, postoperative D90, postoperative D100 and other variables, and to analyze the occurrence of complications. Results: The objective response rate of CT-guided 125I seed implantation in the treatment of mediastinal lymph node metastasis of lung cancer was 75% (27/36), the median control time was 12 months, the 1-year local control rate was 47.2% (17/36), and the median survival time was 17 months. The 1-year and 2-year survival rates were 61.1% (22/36) and 22.2% (8/36) respectively. Univariate analysis showed that in the treatment of mediastinal lymph node metastasis with CT-guided 125I implantation, factors related to local control included tumor stage (HR=5.246, 95%CI: 2.243-12.268, P<0.001), postoperative D90 (HR=0.191, 95%CI: 0.085-0.431, P<0.001), postoperative D100 (HR=0.240, 95%CI: 0.108-0.533, P<0.001); The factors affecting survival were tumor stage (HR=2.712, 95%CI: 1.356-5.425, P=0.005), postoperative D90 (HR=0.110, 95%CI: 0.041-0.294, P<0.001), postoperative D100 (HR=0.212, 95%CI: 0.092-0.489, P<0.001). Multivariate analysis showed that tumor stage (HR=5.305, 95%CI: 2.187-12.872, P<0.001) and postoperative D100 (HR=0.237, 95%CI: 0.099-0.568, P<0.001) were correlated with local control rate. Tumor stage (HR=2.347, 95%CI: 1.095-5.032, P=0.028) and postoperative D90 (HR=0.144, 95%CI: 0.051-0.410, P<0.001) were correlated with survival. In terms of complications, 9 of the 36 patients had pneumothorax, and 1 of them was cured by closed thoracic drainage for severe pneumothorax; 5 cases developed pulmonary hemorrhage and 5 cases developed hemoptysis, which recovered after hemostasis treatment. One case developed pulmonary infection and recovered after anti-inflammatory treatment. No radiation esophagitis and radiation pneumonia occurred; No grade 3 or higher complications occurred. Conclusion: 125I seed implantation in the treatment of lung cancer mediastinal lymph node metastasis has a high local control rate and controllable adverse effects.