Squamous-cell carcinoma of the floor of the mouth.

This study was based on the analysis of 100 cases of squamous-cell carcinoma of the floor of the mouth. The male/female ratio was 4.25:1. The peak incidence in women was in the 50 to 59 year age group; in men there was equal frequency in each age group above 50. The five-year survival rate decreased from 86 per cent to 0 as the stage of disease progressed from I to IV. The five-year survival for all stages of disease was 52.7 per cent. Thirty-three per cent developed new primary malignancies; 22 per cent were of the upper alimentary and respiratory tracts. Distant metastases were present in 21 per cent. Fifty per cent were heavy smokers, 33 per cent were heavy drinkers, 28 per cent were both heavy smokers and heavy drinkers, and 21 per cent were nonsmokers and nondrinkers.