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