The statistics of the Connecticut Tumor Registry on cancer of the floor of the mouth were reviewed for 1935 to 1959. The majority of the lesions were epidermoid carcinoma and the disease is ...predominantly of men (10 to 1) in the older age groups. The over‐all incidence (age‐adjusted) for both sexes combined was 0.9 cases per 100,000 population, 1.8 for men and 0.1 for women. The site, floor of mouth, composed approximately one fifth of all oral cancer. The lesion was localized in 47% of all cases at the time of diagnosis and there was regional involvement in 41%. Approximately one half the patients (54%) were treated by irradiation alone; one quarter (24%) were treated solely by surgical measures. The over‐all observed 5‐year survival rate was 28% with a value of 41% for those whose disease was localized.
