Late-course Accelerated Hyperfractionation Radiotherapy for Nasopharyngeal Carcinoma

[Purpose] To evaluate the clinical results of late-course accelerated hyperfractionation(LCAF)radiotherapy for nasopharyngeal carcinoma(NPC)patients.[Methods] Forty-five NPC patients were divided into conventional fractionation(CF)and LCAF radiotherapy groups.Twenty-two patients in CF group received conventional radiotherapy:2.0Gy/F for 5 fractions a week to a total dose of 70Gy～72Gy/DT.Twenty-three patients in LCAF group were treated with the same conventional fractionation as CF group until the dose of 38Gy～40Gy,then followed by LCAF radiotherapy:1.5Gy/F,twice per day with 6 hours interval between the two fractions,to a total dose of 72Gy～76Gy/DT.[Results]With assessment for primary tumor 3 months after radiotherapy,complete response rate was 100% in LCAF group and 90.91% in CF group 3 months after radiotherapy.The 1-,3-year local control rate was 100%,90.91% in the LCAF group and 95.45%,67.53% in CF group respectively with significant difference(χ2=4.03,P0.05).The 1-,3-year survival rate was 95.65%,73.91% in LCAF group and 95.45%,63.64% in CF group respectively(χ2=0.59,P0.05).The oropharyngeal mucosa grade Ⅲ acute radiation toxicity was 12/23(52.17%)in LCAF group and 4/22(18.18%)in CF group(χ2=4.28,P0.05).The late radiation toxicity was not significantly different between the two groups.[Conclusion] The local control rate of NPC treated by LCAF radiotherapy is superior to that by CF radiotherapy.There is no significant difference in the survival rates between the two groups.The acute radiation toxicity in LCAF group was more severe than that in CF group,however it is tolerable in majority of patients.