[A clinical study of 1079 patients with laryngeal cancer]

A clinical study was made of 1079 patients with previously untreated laryngeal cancer registered in our department during the 15 years between 1979 and 1993. Their mean age was 64.2 years, ranging from 22 to 91. The male to female ratio was 13:1 and the proportion of non-smokers was 3.2%. These patients consisted of 687 with glottic carcinoma (64%), 373 with supraglottic carcinoma (35%) and 12 with subglottic carcinoma (1%). A sexual difference with regard to the proportion of glottic carcinoma was found; 66% in males and 39% in females. Therefore, the male to female ratios according to the primary sites were 22:1 for the glottis and 8:1 for the supraglottis. According to the TNM classification (UICC 1987), there was a marked difference in the distribution between glottic type and supraglottic type: of the glottic type 439 cases (64%) were stage I, 159 (23%) stage II, 73 (11%) stage III, 16 (2%) stage IV, whereas of the supraglottic type 22 (6%) were stage I, 99 (27%) stage II, 136 (36%) stage III, 116 (31%) stage IV. Our treatment policy for laryngeal cancer has depended not only on the T stage but also on the cancer characteristics including the growing type, anatomical location and extension and depth of invasion. Of the 1079 patients, 1050 were treated radically, 17 palliatively and 12 were not treated. According to the T stage, radical irradiation was chosen for 410 cases (93%) of glottic T1, for 75 cases (45%) of glottic T2 and for 21 cases (81%) of supraglottic T1. Partial laryngectomy was performed in 16 patients (4%) with glottic T1, in 15 patients (10%) with glottic T2 and in 8 patients (6%) with supraglottic T2. Total laryngectomy was performed in almost all patients with T3, T4. The overall 5-year relative survival rate, cumulative crude survival rate and cause-specific survival rate were 84%, 72% and 88%, respectively. The survival rates for the glottic type were significantly higher than those for the supraglottic type (p < 0.0001): the 5-year relative survival rate, cumulative crude survival rate and cause-specific survival rate for the glottic type were 93%, 80%, and 95% whereas for the supraglottic type they were 68%, 58% and 76%, respectively. The 5-year relative survival rates for stage I through stage IV were 96%, 87%, 72% and 53% overall and they were 98%, 91%, 74% and 52% for the glottic type, whereas they were 67%, 83%, 70% and 52% for the supraglottic type, respectively. The results suggested that the better survival rate for glottic T1, which accounted for 64% of all glottic cases, made a great difference in the survival rate between glottic and supraglottic carcinoma.