Comparison of side effects of intensity modulated radiotherapy and conventional radiotherapy in nasopharyngeal carcinoma

Objective:To compare the side effects of intensity modulated radiotherapy(IMRT) and conventional radiotherapy in nasopharyngeal carcinoma.Methods:Among 118 cases of nasopharyngeal carcinoma,there were 61 of IMRT and 57 of conventional radiotherapy.The target areas in IMRT were nasopharyngeal carcinoma,parapharyngeal space and neck lymphatic area with the fractional dose of 2.0～2.5 Gy/time,for 33 times.The conventional radiotherapy group was given face-neck joint radiation,DT 40～60 Gy,20～30 times for 4～6 weeks.The reinforcing dosage in pre-auricular field increased to DT 70 GY in the nasopharyngeal area.The total amount of neck prevention was DT 50～55 Gy.Results:The 1-year dry mouth incidence in the IMRT and conventional radiotherapy groups was 8.20%(5/ 61) and 94.73%(54/%57) respectively,the incidence of difficulty in opening mouth in the IMRT and conventional radiotherapy groups was 4.92%(3/61) and 71.93%(41/57) respectively.There was significant difference between the two groups(P0.01).Conclusion:IMRT decreases obviously the side effects compared with the conventional radiotherapy.