[en] To improve the local control rate and to minimize the complication rate of radiotherapy of T2 glottic cancer, we concluded a prospective trial of twice-a-day fractionation radiation therapy (TDFR) and compared the results with those among patients with the stage same of cancer in a historical radiation method group. Forty-two cases of T2 glottic cancer were treated with TDFR between 1986 and 1992. Radiotherapy consisted of a fractionated dose of 1.5 Gy, twice a day, 10 times a week and a total dose of 66-72 Gy in 5 to 8 weeks. We also evaluated the acute and late normal tissue reactions (NTR) of TDFR and conventional radiotherapy with which patients with T1 glottic cancer were treated during the same period. There was no significant difference in NTR between the two groups. Recurrence and survival rates were compared between patients with T2 glottic cancer in the TDFR group and the historical group in same cancer stage. The 5-year local control rate was 75.6% in the TDFR group and 73.2% in the control group. Moreover, there were no significant differences in local control or survival rates. These data suggest that TDFR is useful not only in terms of acute and late toxicity but survival. Prospective randomized trials are recommended for a multicentric study. (author)