[Brachytherapy--carcinoma of the tongue]

In a review of 193 patients with carcinoma of the tongue who underwent interstitial radiotherapy in our hospital from November 1978 to 1986, 5 year actuarial local control rate were 97%, 87%, 58% and 77% for T1, T2, T3 and T4 respectively. Mucosal ulcers with tissue defects and bone exposure of the mandible occurred in 5 years after the treatments, 6%, 22%, 44%, and 100% for T1, T2, T3 and T4, respectively. Therapeutic ratio was 1 in patients with T1 who underwent interstitial radiotherapy (70 Gy/7 days) alone while it was less than 1 in those with T2 or more. Therapeutic gain factor was less than 1 in patients with combined external radiotherapy.