Proton heavy ion cannot cure colon cancer at present. The new technology of Proton Heavy Ion Therapy for cancer has become a hotspot in the medical field to attack cancer, and has been widely used in the treatment of many tumors. However, for tumor treatment, each treatment method has its own scope of application, so proton heavy ion technology cannot be used for all cancer treatment. In the following cases, proton heavy ion therapy cannot be applied. 1. Non-solid tumors: hematological tumors such as leukemia. 2. Tumors of cavity organs: gastric cancer, esophageal cancer, colorectal cancer, etc. 3. Tumors with multiple distant metastases and ≥3 metastatic foci. 4. Received radiation therapy or radioactive particle implantation in the same area within 1 year. Although proton heavy ion cannot cure colon cancer at present, if colon cancer is found early and timely after radical colon cancer surgery, the 5-year survival rate is still good.