Results: 18FDG PET / CT changed the volume of radiotherapy to the tumor in 95.16% of patients (increased 50.0%, decreased 45.16%) and 90.33% in lymph nodes (increased in 64.52%, decreased 25.80%); the average tumor length determined on 18FDG PET / CT and on CT was 7.86 ± 3.68 cm and 8.66 ± 3.36 cm (p < 0.05); the average number of lymph nodes detected on 18FDG PET / CT and CT was 8.66 ± 3.16 cm and 7.35 ± 3.23 cm (p > 0.05); The maximum absorbed dose at the tumor compared with the indicated dose in the 18FDG PET / CT plan was 105.07 ± 1.56%, which was 104.76 ± 2.28% higher than the one in the CT plan of 104.76 ± 2.28% (p > 0.05); rate of complete response after treatment is 22.22%, partial response is 44.44%, non-responder is 25.93% and progression is 7.41%.