Particle knife can treat solid tumors in all parts of the body. Indications include: 1. untreated primary tumors, such as prostate cancer, lung cancer, etc. 2.Important functional tissues that need to be preserved or the surgery will involve important organs, such as tumors deep in the brain. 3.Cases in which patients are unwilling to undergo radical resection, such as thyroid cancer, endometrial cancer, tongue cancer, etc. 4.Prophylactic implantation is performed during surgery to prevent local or regional spread of tumor and enhance the radical effect. 5.Metastatic tumor lesions or postoperative isolated tumor metastases that lose their surgical value, such as multiple metastatic tumors of the lung. 6. Inoperable primary cases, such as giant hepatocellular carcinoma, lung cancer, nasopharyngeal carcinoma, etc. 7. Tumor infiltrating important organs cannot be completely removed. 8. Cases with poor or failed external irradiation effect, etc. 9. Chemotherapy-resistant patients.