Patients with recurrence after radiotherapy are often encountered in clinical practice.Patients with recurrence after radiotherapy are less likely to undergo surgery or secondary radiotherapy, and the guidelines recommend only systemic therapy, although the effective rate is relatively low.For patients with local recurrence without distant metastasis, local treatment is still significant.Radioactive I-125 Seed Implantation (RISI) treatment is to I-125 Radioactive nuclide directly inside the implanted tumors, make its rays to continuous destruction of tumor cells, have inside the tumor target high dose, low dose of normal tissue around, and its radiation is low dose rate, in theory, more conducive to the protection of the normal tissue, more suitable for salvage treatment of recurrence after radiotherapy lesions.Some retrospective studies on RISI treatment of NSCLC showed that the local control rate was up to 25%-80%, and there were few reports of toxic and side effects, suggesting that it had good efficiency and safety.Therefore, for patients with recurrent NSCLC after chest radiotherapy, RISI may be considered.And template technology, 3 d printing is a new kind of technology in recent years, can be individualized and human body surface, the guide posts on the the direction of the puncture needle can be accurately controlled, the current data show that in the template with CT guided by solid tumors as well had significantly higher accuracy, as the actual target dose of basic postoperative can reach the design request of the preoperative planning, so the application of 3D printing template helps to further improve the operation efficiency and safety, also has potential promotion effect to curative effect.The purpose of this study was: (1) to observe the efficacy, toxic and side effects of RISI in the treatment of recurrent NSCLC after radiotherapy under the guidance of 3D printing template assisted CT, and to evaluate its safety and effectiveness;(2) to explore the relationship between the efficacy, toxicity and side effects of RISI dose in the treatment of recurrent NSCLC after radiotherapy;(3) analyze the relevant influencing factors affecting the effect/toxicity of RISI in the treatment of recurrent NSCLC after radiotherapy.