[Lung cancer screening: status in 2007].

Thoughts on screening for lung cancer are based on the very poor prognosis of this tumor when the diagnosis is made because of symptoms (<15% 5-year survival), the markedly better prognosis if it is detected in asymptomatic early stages (up to 80% 5-year survival), the high sensitivity of unenhanced low-dose CT in the detection of small tumors, and the clear definition of persons at risk. Feasibility studies using well-defined diagnostic algorithms for management of detected pulmonary nodules have demonstrated a high proportion (>50 to >90%) of small, resectable non-small-cell lung carcinomas in the early stages, with a good prognosis for the patients affected and a low rate of unnecessary biopsies. However, biases such as overdiagnosis, length-time and lead-time could hamper potential reduction of mortality from lung cancer, and the results of large prospective randomized trials are therefore awaited. At the same time, other techniques for early diagnosis of lung cancer are under evaluation, such as sophisticated methods of sputum analysis, molecular markers in the blood and analysis of exhaled air.