The side effects of iodine 125 particle implantation include: 1. Life-threatening: Some tumor patients may have decreased hematopoietic function after anti-tumor treatment, if the prognosis is not accurate, after taking iodine 125 particle implantation treatment, it may cause worse hematopoietic function, and the white blood cells, red blood cells and platelets in the blood will be significantly decreased without the patients’ knowledge, which will be life-threatening in serious cases; 2. Particle shedding: If particles are shed and lost, it will cause great damage to the surrounding objects and life, etc. The use of iodine 125 particles in hospitals requires the ingestion of such substances through isotopes. Therefore, only hospitals with isotope particle storage and transportation qualifications can apply iodine 125 particle implantation therapy.