We analyzed the influence of various parameters on the results of radiotherapy for T1 glottic cancer by assessing the outcomes of 60 patients with this cancer who received definitive radiotherapy between 1985 and 1994. Seven patients were treated with a cobalt-60 unit, and the other 53 with a linear accelerator (26 patients at 3-MV, 10 at 6-MV, and 17 at 10-MV). Of the 17 patients treated at 10-MV, 4 also received part of their treatment with a cobalt-60 unit. The total radiation dose ranged from 56Gy to 70Gy (mean, 61 Gy). The total radiation dose of 51 patients (85%) was 60Gy. The factors found to influence local control were the strength of the radiation beam energy and whether or not there was gross tumor invasion of the anterior commissure. The local control rate was 71 % in the patients treated with a 10-MV linear accelerator, 56% in those treated with a 6-MV linear accelerator and, 97% in those treated with a cobalt-60 unit or a 3-MV linear accelerator (P = 0.0173). The local control rate was 43% in the patients with gross anterior commissure invasion and 88% in those without (P = 0.0075). We conclude that low energy photon beams are more suitable for the treatment of early glottic cancers, especially if the lesion grossly invades the anterior commissure.
|Number of pages||4|
|Journal||Acta medica Okayama|
|Publication status||Published - Dec 1 1999|
- Radiation beam energy
- T1 glottic cancers
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)