During radiation therapy for patients with tumors, the most important thing to note is that the marker spots on the skin should be protected to avoid loss. In addition, according to the doctor’s instruction, regular monitoring and examination, such as blood routine, electrolytes, liver and kidney function and other indicators. In case of more serious discomfort, the competent doctor should be informed promptly. More detailed aspects are explained in detail by the doctor during radiation therapy, for example, for radiation therapy of esophagogastric junction cancer, the stomach needs to be filled up, and the patient should drink 800-1000ml of water before CT positioning to make the stomach fill up better. During the radiation treatment, this amount of water needs to be repeated during each radiation treatment. In addition, patients need to hold urine before radiation therapy for rectal cancer to fill up the bladder and reduce bladder damage. It is very important to pay attention to rest, reasonable nutrition, maintain a good state of mind, and communicate with doctors in time.