Acute side effects of helical tomotherapy and conventional intensity-modulated radiation therapy for cervical carcinoma after operation

Objective To observe the acute side effects of helical tomotherapy（HT） and conventional intensity-modulated radiotherapy（IMRT） for cervical carcinoma after operation and the difference in dosages used in organs at a high risk（OAR）.Methods Of the 126 patients with cervical carcinoma,68 received HT and 58 underwent IMRT after operation.The irradiation dose for the total pelvic and the drainage region of lymph nodes at a high risk was 46-50.4 Gy/23-28F and 60 Gy/28F,respectively.Routine blood examination,acute side effects of rectum and bladder were evaluated following the radiation therapy oncology group（RTOG） and European organization for research on treatment of cancer（EPRTC） scoring criteria.Conformity index（CI） and homogeneity index（HI） of target volume were evaluated according to the dose volume histograms（DVH）.Results The incidence of grade one acute side effects of HT and IMRT in rectum and bladder was 27.94% and 46.55%（χ²=4.68,P＜0.05）,and 17.65% and 24.13%（χ²=1.93,P＞0.05）,respectively.No acute side effects with a grade≥2 occurred after HT and IMRT.The CI and HI of clinical target volume were 0.73+0.082 and 1.047+0.026,0.686+0.072 and 1.13+0.017,respectively,after HT and IMRT.Conclusion HT is more advantageous over IMRT pelvic and has a better protection effect on normal tissue in patients with cervical carcinoma after operation.