Abstract: Objective The efficacy and toxicity of concurrent chemoradiotherapy(CRT)with concurrent bolus and CRT with conventional fractionation and shrinking field for nasopharyngeal carcinoma(NPC)were compared.Methods A retrospective analysis was performed in 90 patients with NPC who received radiotherapy and chemotherapy in our hospital from January 2007 to December 2008.The 5-year overall survival(OS),progression free survival(PFS),local recurrence free survival(LRFS)and toxicity were compared between the two groups.Results The 5-year OS,PFS and LRFS of CRT with concurrent bolus group were 84.4%,75.6% and 88.9%,respectively,while those of CRT with conventional fractionated field group were 82.2%,71.1% and 86.7%,respectively.There were no differences of OS,PFS and LRFS between the CRT with concurrent bolus and conventional fractionated field groups.The radiation response of brainstem,spinal cord and parotid gland in the conventional fractionated field CRT group was lighter than that in the CRT with concurrent bolus group.Conclusion There is no significant difference in the prognosis between the CRT with concurrent bolus and conventional fractionated field groups in the ear of intensity modulated radiation therapy,but the toxicity of CRT with conventional fractionated field group is lighter.

Key words: Nasopharyngeal carcinoma, Concurrent bolus radiotherapy, Conventional fractionated retroflex field radiotherapy, Concurrent chemoradiotherapy, Toxicity