[Radiotherapy of laryngeal cancer]

In general, the control rate with radiotherapy in early laryngeal cancer is close to 90%, probably the highest control rate that can be expected with this therapy. In other words, about 10% of patients still fail to respond to the therapy. This probably means nothing but the fact that the sigmoid response curve has reached the plateau. This ratio has remained unchanged, while physical and biological dose distribution has remarkably been improved these three decades. In this study, therefore, we discussed the cause of radioresistance in squamous metaplasia of laryngeal epithelium as the origin of laryngeal cancer.