The time-dose relationship for the combination of external irradiation with interstitial radium implant in carcinoma of the oral cavity

32 patients were treated by external irradiation combined with interstitial radium implant. These included 19 patients with carcinoma of the tongue, 8 patients with carcinoma of the floor of mouth and 5 patients with other carcinoma of the oral cavity. 5 patients with Stage II disease, 17 with Stage III and 10 with Stage IV. 24 patients survived more than 1 year. The control rate of the primary lesion was 75%. 10 of 11 patients with T3 carcinoma of the tongue were controlled. Types of complication included mandibular necrosis in 1 case and severe ulceration in 3 cases. The severe complications were observed in patients treated with dose ranging 127 - 162 T.D.F. The optimum dosage for T3 cancer of oral cavity was considered to be 4000 rad in 20 fractions in 4 weeks by external irradiation followed by 4000 rad given in 4 days an implant. The nature of complications depends on the site of the primary lesion and the implantation technique. (author)