Non small cell lung cancer is the most common histologic type (80 to 85%) with an incidence of 20 to 25,000 cases by year in France. Almost fifty per cent of cases are stage IV disease, at diagnosis and the treatment is palliative by chemotherapy. Locally advanced disease is treated by an association of chemo and radiotherapy. At the early stage, the treatment consists of surgery combined with chemotherapy. New drugs, new biologic therapeutics, the improvement of surgical procedures and radiotherapy, and combined treatment have increased the survival rate (15% at 5 years survival). Nevertheless, prevention ("war" against tobacco) early diagnosis and perhaps CT scan screening remains the best way of decreasing the number of deaths by lung cancer.