Results of radiotherapy of carcinoma laryngis in relation to the mode of dose fractionation.

The effectiveness of a new fractionation scheme of radiotherapy of carcinoma laryngis was investigated. The irradiation was applied every second day 3 times a week with a fractionation dose of 4 Gy and 3.5 Gy--TD 52 or 52.5 Gy. The results from 95 patients were compared with those from 129 patients irradiated with the conventional fractionation. The cumulative results of primarily healed patients treated with the new fractionation scheme proved significantly better. In supraglottic carcinoma the results of primary healing were on the whole better, although statistical significance could be proved only in stages I and II. In glottic carcinoma, a difference of statistical significance was found in the total number of patients in stages I and III. A higher effectiveness was noted in the 3.5 Gy as against the 4 Gy fractionation. A higher frequency of stronger mucous reactions and delayed radiation oedema occurred with the new fractionation scheme. No complications of a serious degree occurred.