Glottic and supraglottic laryngeal carcinoma: differences in epidemiology, clinical characteristics and prognosis.

In order to evaluate differences in epidemiology, clinical characteristics and prognosis, 166 glottic and 127 supraglottic cases of laryngeal squamous cell carcinoma diagnosed between 1962 and 1991 at Tampere University Hospital, Finland, were reviewed. The annual age-adjusted incidence in males decreased from 6.7/100,000 to 2.6/100,000 and the proportion of glottic tumours increased from one-third to two-thirds during the study period. The proportion of early stage lesions was greater among glottic tumours, and patients with a supraglottic tumour presented more often with neck node metastases. Hoarseness was the most common symptom, being more prevalent in patients with a glottic tumour. The symptom pattern of supraglottic carcinoma was altogether more diffuse. The 5-year disease-specific survival was 81% in glottic and 70% in supraglottic disease, but the difference in survival was not statistically significant. In the multivariate Cox regression analysis, higher T-category and presence of neck node metastases had adverse prognostic effect, while location of the tumour did not significantly affect the prognosis. Favourable changes in smoking habits seem to be the main reason for the incidence decrease and obviously also for the decrease in the proportion of supraglottic tumours.