Data from 452 patients who underwent pulmonary resection for a non small cell bronchogenic carcinoma from 1980 to 1985 were analysed retrospectively. The operative mortality rate was 5.5%. Mortality was significantly increased in patients who underwent enlarged resections for T4 tumors (20%; p < or = 0.05), and in patients who were 70 years and older (12.8%; p < or = 0.05). The overall 5-years survival rate was 32.7% at 5 years. Prognosis in patients who were 70 years and older was similar to that in younger patients. No difference in survival was observed in patients with lymph node metastases with regard to the operative procedure (pneumonectomy versus lobectomy). Survival in patients without lymph node metastases who underwent a lobectomy was similar to those who underwent a conservative resection. Prognostic significance of the histologic cell type and the tumor formula (pTNM) was assessed by multivariable analysis. There were statistically significant differences between squamous cell carcinoma and both adenocarcinoma (p < or = 10(-5)) and undifferentiated carcinoma (p < or = 0.01). This study confirmed the validity of the TNM classification (4th ed) for the accurate prognosis evaluation. Lymph node involvement appeared to be the most pejorative factor (p < or = 10(-5)).