[Hyperfractionated radiation therapy for head and neck cancers]

Among various altered fractionation regimens, hyperfractionated radiotherapy (HFRT) has been considered effective to raise survival rate(SR)as well as local control rate(LCR)in head and neck cancers. We reviewed our results of HFRT (117 cases) treated between 1995 and 2004 and compared with those of conventionally fractionated radiotherapy (CFRT; 80 cases) treated during the same period. By disease site, naso-/oro-/hypopharynx/larynx were 5/23/44/45 vs. 10/6/10/54. There were more advanced-stage cases in HFRT group (stage I/II/III/IV = 19/36/23/35 vs. 42/16/8/ 14). Median RT dose were 72 Gy vs. 66 Gy. In 71 cases, chemotherapy was added (HF/CF = 54/17). In stage III and IV cases, there was a borderline significant difference in LCR (at 5 years; 44.3% for HFRT group vs. 24.5% for CFRT group; p = 0.0502), and a tendency in SR(at 5 years; 50.7% for HFRT group vs. 16.7% for CFRT group; p = 0.1210). By disease site, LCR of HFRT group was higher in hypopharynx(p = 0.0005)and oropharynx(p = 0.0003), and SR of HFRT group was higher in hypopharynx(p = 0.0023). Acute toxicity was heavy but in most cases it was tolerable and there were no severe late toxicities. From our data, it was suggested that HFRT might be effective in certain kinds of head and neck cancers.