Clinical evaluations of pre-operative irradiation for carcinoma of the lower gum

From April 1975 through March 1984, 34 patients with primary squamous cell carcinoma of the lower gum received preoperative irradiation. The cumulative survival rate at 5 years was 76 %. Although prognosis was well correlated with longitudinal diameter of carcinoma, it was independent of whether or not carcioma invaded the mandible. There was no difference in survival rates between the groups with or without chemotherapy. In the case of low dose irradiation, histopathological criteria for radiation were greater in the group with chemotherapy than in the group without it. Histopathological grade of radiation effect was III or IV in 59 % of the patients. The 5-year cumulative survival rate in these patients was 92 %, being significantly better than that in the patients with grade I or II effect (51 %). (Namekawa, K.)