Treatment results in oral squamous cell carcinoma with hyperfractionated radiotherapy. Preliminary report

Between December 1990 and November 1993, 21 cases of squamous cell carcinoma of the oral region were treated with twice-a-day irradiation (1.2 Gy/fraction, 4-hour interfraction interval). Ten of the patients had T4 tumors. Seventeen patients received irradiation alone to the primary site. The total dose administered was 70.8-74.4 Gy in the majority of cases. In all cases except one, the treatment was completed without a rest interval. Local control results at two years and the time of assessment were 1/2 and 1/2 for T1 tumors, 4/6 and 5/8 for T2 tumors, 0/1 and 0/1 for T3 tumors and 1/7 and 2/10 for T4 tumors. T stage was a significant prognostic factor for local control (p=0.007). The local control rate did not correlate well with the total dose (P=0.103). Only one pathologic fracture of the mandible was observed as a complication. It was considered that this treatment regimen was preferable for T1 and T2 tumors in respect of local control but was not sufficient for T3 and T4 tumors. (author)