Surgical treatment, radiation therapy and chemotherapy are the three well-known malignant tumor treatment techniques. As one of the three conventional treatments for tumors, radiation therapy occupies an important position in the field of tumor treatment, and it is estimated that radiation therapy is needed in 70% of malignant tumors at different stages of treatment (including comprehensive treatment and individual treatment). At present, the most widely used radiotherapy is photon radiotherapy, which uses high-energy X-rays or gamma rays to treat tumors. With the development of science and technology, a new radiotherapy technique, proton heavy ion radiotherapy, has come into people’s view. Domestic and foreign years of proton and heavy ion clinical application and experimental research shows that proton heavy ion radiotherapy effect is better than photon radiotherapy, radiotherapy toxic side effects and adverse reactions are significantly less than photon. What is proton heavy ion] Proton is a particle with positive charge after the hydrogen atom is stripped of electrons. Heavy ions are the nuclei or ions of carbon, neon, silicon and other atomic weight. Protons or heavy ions are accelerated to 70% of the speed of light by a synchrotron and then introduced into the treatment room and shot at the human body. The energy of the rays is hardly released before reaching the established treatment target area, and a large amount of energy is released instantly after reaching the lesion, which forms a “Bragg” peak energy release trajectory. It is internationally recognized as the most advanced radiotherapy technology, which can irradiate cancerous lesions while leaving the surrounding normal tissues virtually untouched. The physical dose distribution and biological effects of X-rays and gamma rays are not ideal, and they often cause certain degree of irradiation damage to the normal tissues around the cancer when applied. While the biological effects of neutrons and negative π ions are good, the physical dose distribution is not ideal and the damage to normal tissues is too great, neither of which is an ideal treatment method. In contrast, proton heavy ions can form an energy release trajectory like a “Bragg” peak, and the energy is hardly released until it reaches the lesion, thus achieving a powerful killing effect on tumor cells while effectively protecting the surrounding normal tissues, thus reducing the side effects caused by the treatment. Proton therapy has a wide range of indications because of its high energy and penetrating characteristics, making its indications significantly broader than those of ordinary photon therapy. Currently, the indications for proton therapy include: Central nervous system: meningioma, glioma, etc. Skull base: chordoma, chondrosarcoma, etc. Head and neck: nasopharyngeal carcinoma, adenoid cystic carcinoma, melanoma, soft tissue sarcoma, and other recurrent tumors Thorax: lung cancer, esophageal cancer, mediastinal tumors, etc. Abdominopelvic cavity: liver cancer, pancreatic cancer, bile duct cancer, prostate cancer, rectal cancer, uterine tumors, and other unresectable pelvic tumors, etc. etc. Other sites: bone tumors, soft tissue sarcomas, etc. High cure rate The results of clinical treatment show that proton and heavy ion radiotherapy have achieved relatively good efficacy in the treatment of non-small cell lung cancer, prostate cancer, head and neck tumors, liver cancer, skull base and paraspinal tumors and central nervous system tumors, while the acute and late radiotherapy adverse effects are not serious. Heavy ions are highly lethal to tumors, especially those that resist photon radiotherapy or even proton radiotherapy, such as soft tissue sarcomas, adenoid cystic carcinomas, malignant melanomas and other malignant tumors containing large numbers of oxygen-depleted cells. As a new tumor treatment technology, proton heavy ion radiotherapy expands the application width of radiation therapy, greatly improves the cure rate and quality of life of patients treated with tumors, and provides a new choice of treatment modality for patients who are old, have poor cardiopulmonary function or cannot tolerate surgical treatment. However, it is worth mentioning that proton heavy ion radiotherapy is a “powerful tool” rather than a “miracle tool” in the treatment of tumors. In the treatment of many tumors, it is necessary to fully combine multiple treatments according to the specific patient’s condition in order to obtain the maximum benefit from the treatment.