The authors studied some demographic, clinical, pathologic, and therapeutic variables in relation to the disease-free interval (DFI) and to the overall survival of laryngeal cancer patients. The patient population consisted of 278 consecutive cases of primary laryngeal cancer who had been admitted to four head and neck surgery services in Sao Paulo and Curitiba (Brazil) between 1973 and 1986. All patients had surgical treatment. Although several variables exhibited individual associations with survival, only a few were deemed to have independent prognostic value using multivariate regression techniques based on Cox's proportional hazards model. The primary tumor stage (T index) represented the variable with the highest predictive strength with respect to survival.
Hazard ratios for the risk of disease recurrence were 2.3 (Tz-3 vs. T,) and 4.3 (T4 vs. T,). Hazard ratios for the risk of death were 1.6 (Tzp3 vs. T,) and 3.3 (T4 vs. TI). The following additional factors were also independently associated with the DFI: age, site of primary tumor (transglottic, glottic, or supraglottic), extracapsular spread of lymph node metastasis, surgical margins, type of paratracheal node dissection, and prior tracheostomy. Except for extracapsular spread, the same factors related to the DFI were also significantly related to the overall survival. Race, sex, N-stage, vascular embolization, and histological grade were other independent predictors of the risk of death.