Tumor is one of the diseases that seriously endanger human health. With the further development of modern medicine, the treatment concept of tumor is gradually developing from traditional surgery, chemotherapy and radiotherapy to comprehensive tumor treatment, the ultimate purpose of which is to improve the therapeutic effect of tumor and reduce the toxic side effects to achieve the effect of delaying the survival of patients or curing them. Radionuclide tumor therapy is a kind of system-specific targeted therapy, which mainly uses carriers or takes interventional measures to deliver the radiopharmaceuticals for treatment to the diseased tissues and cells in a targeted manner, and through the active uptake of radiopharmaceuticals by the tissues and cells there, the irradiation dose of radionuclides is mainly gathered in the tumor tissues, and the short-range alpha and beta rays, oscillating electrons, and internal conversion electrons released through the decay of radionuclides are used to generate the biologic effects. Through the biological ionization effects of short-range alpha and beta rays, intermittent electrons and internal conversion electrons released from the decay of radionuclides, the local tissue cells in the irradiated area lose their reproductive capacity, metabolic disorders and cellular senescence or apoptosis (death), thus achieving the therapeutic purpose with minimal damage to the surrounding tissues. This method integrates the advantages of radiation therapy and targeted therapy, and the selective killing of tumor cells makes radionuclide therapy for tumors attract more and more attention and play a pivotal role in the comprehensive treatment of tumors. The current situation of radionuclide therapy and its progress are briefly introduced. 131I has been used in thyroid cancer treatment for more than 50 years in China. 131I has been widely used in clinical practice because of its simplicity, efficacy and practical value. 131I is mainly used for the treatment of postoperative residual tissues and metastases of differentiated thyroid cancer. The efficacy of 131I is directly affected by the extent of residual tissues and metastases and the iodine uptake ability of the metastases, and the efficacy decreases in the order of soft tissue, cervical lymph nodes, lung and bone metastases. Small metastases with strong iodine uptake capacity have the best therapeutic effect, with a 10-year survival rate of 90% according to the literature. Therefore, 131I treatment for differentiated thyroid cancer has become the first choice or classical treatment for postoperative follow-up of these patients. 2. Treatment of metastatic bone pain There are 2 million new cancer patients in China every year, among which 1 million have bone metastasis. Among patients with lung cancer, breast cancer and prostate cancer, about 70%~80% of them have bone metastasis. 70% of patients with bone metastasis have bone pain symptoms. After the occurrence of extensive bone metastases, due to the tension or pressure of the endosteal and eposteal membranes generated by the tumor growth and the direct involvement of the tumor in the periosteum, clinically there is often obvious and intractable bone pain, which seriously affects the quality of life and prognosis of patients. In recent years, the rapid development of radionuclide treatment for bone metastases and relief of metastatic bone pain has gradually replaced the traditional narcotic drugs for bone pain treatment. At present, the main radiopharmaceuticals used for the treatment of bone metastatic cancer are 89SrCL2, 153Sm-EDTMP, 186Re-HEDP and 188Re-HEDP. These drugs are all osteotropic and show obvious concentration in bone metastasis tumor lesions after intravenous injection. The beta-rays emitted by these osteotropic radiopharmaceuticals are used to irradiate the tumor internally to achieve pain relief and suppress or destroy bone metastasis tumor lesions. At the same time, 153Sm, 186Re and 188Re can also emit some γ-rays when decaying, which is beneficial to observe the distribution and concentration of radiopharmaceuticals in the body and evaluate the therapeutic effect by imaging method. Moreover, a large amount of literature at home and abroad shows that its efficiency reaches 80%-90%, which can obviously relieve metastatic bone pain and significantly improve the quality of life of patients, and the toxic side effects are less compared with painkillers, chemotherapy, radiotherapy and hormone therapy. Therefore, radionuclide-targeted therapy for metastatic bone pain has become one of the most promising treatments in clinical treatment of bone metastatic cancer and relief of bone metastatic pain. 3.131I-MIBG for pheochromocytoma The chemical structure of 131I-MIBG is similar to that of norepinephrine, so its absorption and storage mechanism is also similar. 131I-MIBG can be taken up by the adrenal medulla and sympathetic nerve richly distributed tissues and organs, and has high affinity with adrenergic tumors. 131I-MIBG can be taken up by all tumor cells with neurosecretory granules after being introduced into the organism. The first choice of treatment for pheochromocytoma is surgical resection, but pheochromocytoma is not sensitive to traditional radiotherapy and chemotherapy after surgery, while more than 95% of pheochromocytoma lesions can highly selectively take up 131I-MIBG (m-iodobenzylguanidine), and then through decay emission of β-rays, the effect of ionizing radiation can kill or inhibit tumor cells to achieve the purpose of treatment, and it is reported through a multicenter study that its The effectiveness rate is reported to be 70% through multicenter studies. The effectiveness of 131I-MIBG has been reported to be 70% in multicenter studies, and the occurrence of serious side effects is rare in the treatment of pheochromocytoma with 131I-MIBG, and only symptomatic and supportive treatment is generally required. 131I-MIBG is also characterized by the possibility of repeated treatment, and can be used in combination with calcium antagonists, vasodilators and radiosensitizers to increase its efficacy. Therefore, 131I-MIBG has become the first choice of treatment for pheochromocytoma after surgery. 4.Radioimmunotherapy for tumor With the development of hybridoma technology, tumor radioimmune-guided therapy is gaining attention because of its extremely strong targeting effect, high tumor/benchmark ratio and low blood background. The principle is to use hybridoma technology to prepare monoclonal antibodies of relevant tumors or DNA recombinant technology to prepare “humanized” genetically engineered antibodies, which are directly radionuclide-labeled or chelator-labeled in vitro to obtain labeled antibodies that meet pharmacopeial requirements. The antibodies are introduced into the body through a certain route and specifically bind to the surface antigens of the tumor cells concerned, using the biological effects of ionizing radiation generated by the α and β rays, oscillating electrons and internal conversion electrons emitted by the various labeled nuclides to kill the tumor cells until death. The following have been clinically applied so far. Table 1 Radioimmune agents used in clinical or preclinical applications Tumor category Radioimmune agents Hematologic malignancies Non-Hodgkin’s lymphoma 90Y-Ibritumomab tiuxetanA 131I-TositumomabA 90Y- Epratuzumab anti-CD22 IgG T-lymphocyte cripples, non-Hodgkin’s lymphoma and Hodgkin’s lymphoma 90Y-Anti-Tac IgG Leukemia 131I-BC8anti -CD45 IgG 213Bi-HuMl95anti-CD33 IgG 188Re-or 90Y-anti-CD66 IgG Solid Tumor Colon cancer 90Y-T84.66 anti-CEA IgG 131I -and 90Y-labetuzumab (anti-CEA IgG) 125I -and131I-A33 IgG 131I-CC49 a?CH2 90Y-Biotin pre-targeted by CC49 a StAv fusion protein ovarian cancer 177Lu -and90Y-CC49 131I-Anti-CEA IgG 90Y-Biotin pre targeted by biofinylated mAb cocktail 90Y-Hu3S193 Prostate cancer 177Lu -J591 IgG Pancreatic cancer 90Y-PAM4 IgG Lung cancer 131I-chTNTA Hepatocellular carcinoma 131I-Hepama I1 IgG 90Y-hAFP IgG Kidney cancer 131I-cG250 IgG Breast cancer 90Y-BrE3 Glioma 131I I81C6 antitenascin neuro Glioma 211At I81C6 90Y-BC2 and BC4 antitenascin 90Y-Biotin pre-targeted by biotin-BC4 125I I425 lgG Central system or cerebrospinal tumor 131I I8H9 lgG medulloblastoma 131I I3F8 IgG head and neck tumor 186Re-Bivatuzumab IgG medullary thyroid cancer 131I-Hapten pre-targeted by anti -CEA bsmAb superscript A: radioimmune agents approved for clinical use by the U.S. FDA (Food and Drug Administration) The efficacy of various radioimmune agents used in clinical treatment of tumors varies, but in general, they can achieve more satisfactory efficacy, as evidenced by studies, especially 90Y Ibritumomab tiuxetan and 131I-Tositumomab can achieve response rates of 60% to 80%, complete remission rates of 30% and average remission periods of 5 years in the treatment of non-Hodgkin’s lymphoma. However, it has the limitations of human anti-mouse antibody (HAIlA) immunogenic response and low tumor uptake of the antibody. At present, genetic engineering technology is used to modify murine antibodies to make them “humanized”. This reconstituted antibody contains low amount of murine protein, small molecular weight, strong penetration into tumor tissues, high specificity and high affinity, and less chance to produce HAMA. At the same time, dual-functional sting labeling technology is used to label anti-tumor genetically engineered antibodies with short half-life nucleophiles such as 188Re, which has short circulation time in blood; less damage to liver and bone marrow; rapid clearance of markers, lower blood background, and improved target/non-target ratio, in order to expect to bring more room for development of RIA in clinical application. 5.receptor-mediated targeted therapy Tumor cells in the process of mutation and differentiation, the expression of certain receptors in the cell membrane can be significantly increased, using the interaction between receptors and ligands (neurotransmitters, hormones, drugs or toxins, etc.), the radionuclide-labeled ligands, i.e. radioactive ligands, are introduced into the body to reach the corresponding high-density tumor receptor target organs, and the ligands bind with high specificity and affinity to the tumor cell receptors to form a radioactive receptor-ligand complex. The ligand binds to the tumor cell receptor with high specificity and affinity to form a radioactive receptor-ligand complex, which emits nuclear radiation and generates ionizing radiation biological effect, as well as using the receptor-ligand-loaded drug to enter the tumor lesion tissue to play a two-way effect, thus achieving the purpose of inhibiting or killing cancer cells. At present, there are more researches on radionuclide therapy mediated by growth inhibitor receptor, vasoactive intestinal peptide receptor, folate receptor, tumor necrosis factor receptor and so on. It is mainly used for neuroendocrine tumors; small cell lung cancer: breast cancer; adenocarcinoma of the digestive tract. It has better efficacy for receptor-dense tumors, especially for the treatment of extensive and scattered metastases, which is superior to other methods. 6.Radionuclide inter-tissue intervention The radionuclide 32P or 90Y a colloid, a glass microsphere or 125I particles are implanted into the substantial tumor tissue with precise dose calculation and positioning under the guidance of ultrasound, CT or using advanced treatment planning system (TPS), and it is retained for a long time, using the radionuclide to continuously decay to spontaneously radiate Y-rays The mechanism of the combined effect of Y-rays, electron capture in nuclear decay, and tough radiation constantly irradiates the lesion site, and produces sufficient biological effect of ionizing radiation in the local radiation-sensitive proliferating tumor cells, through direct action, i.e., direct damage or destruction of living biologically active macromolecules (proteins, enzymes, nucleotides, etc.) and indirect action, i.e., ionization of water molecules in the body to produce free radicals (H, OH) and hydronium (e). OH) and hydrated electrons (e-1aq) interact with biological macromolecules, causing damage to tissue cells and effectively inhibiting or destroying diseased tissues, resulting in the loss of reproductive capacity, metabolic disorders, cellular aging or death of continuously irradiated cells, thus achieving therapeutic purposes. It mainly treats prostate cancer, cervical cancer, ovarian cancer, breast cancer, esophageal and gastric cancer, bronchial cancer and bronchopulmonary cancer, brain tumor, eye and nasal tumor and craniopharyngeal tumor, etc. Gene therapy is the hot spot of tumor treatment research in recent years. Gene therapy methods that are still in experimental research or preliminary clinical application include immune gene therapy, multi-drug resistance gene therapy, antisense oligonucleotide therapy (antisense therapy) in tumor cells, inducing tumor cells that do not take up radionuclides themselves to specifically take up a certain radionuclide, forming a gene therapy with The dual killing effect of radionuclide and suicide gene on tumor cells has opened up a brand new way for tumor gene therapy. At present, the comprehensive treatment of tumor is the focus of great attention in the medical field. The results of a large number of clinical data prove that tumor nuclear therapy is an effective treatment method that can reduce the pain of tumor patients, improve the quality and prolong the survival time of patients. With the development of genetically engineered antibodies, the use of gene-targeted nuclear therapy and the rapid development of molecular nuclear medicine, it can be predicted that the applied research of radionuclide therapy is getting more and more attention at home and abroad. The potential for further exploration and development of the role of radionuclide therapy is not to be underestimated.