Low dose rate brachytherapy and results

In the autumn 1978, we restarted brachytherapy in Kyushu University Hospital. In patients with carcinoma of the tongue, the local control rates of T1-2 lesions were almost 100%. By the use of a spacer, the late complication rate was reduced from 21% down to 7-12%. Additional external irradiation up to 20Gy, did not increase radiation injury rate. In patients with carcinoma of the uterine cervix, our half length tube of ¹²³Cs, reduced the rectal injury rate. The calculations of ICRU rectal doses and 10% rectal injury doses, revealed that the dose rate factor (low dose rate/high dose rate) was 1.3.