Side effects of radiotherapy for esophageal cancer are as follows: 1. Acute radiation dermatitis: appears 10-20 days after radiotherapy, the time of appearance varies from person to person; 2. Radioactive esophagitis: appears after 2 weeks, manifested as pain in the throat and difficulty in swallowing; 3. Radioactive tracheal reaction: patients have dry cough, no sputum and other symptoms; 4. Radioactive costochondritis: rib damage or even fracture after radiotherapy; 5. Esophageal perforation: the condition is serious and even fatal; 6. Esophageal stricture: in the distant stage of radiotherapy, local fibrosis and scarring in the esophagus cause esophageal stricture; 7. Dietary difficulties: leads to nutritional disorders and gastrointestinal reactions, etc.