Fig. 2, patient radiotherapy plan, A and B are one-course radiotherapy plans, PTV: 5000 cGy/25f, GTVnd: 5000 cGy /25f; C and D are two- course radiotherapy plan: PTV:1000 cGy/5f, and GTVnd: 1000 cGy/5f. The focus of lung cancer was smaller than before during two-course radiotherapy.