[Prerequisites for a successful lung cancer screening program].

The American national lung cancer screening trial (NLST) has provided the first confirmation of a reduction in lung cancer mortality by using low-dose multislice computed tomography (MSCT). Preliminary evaluations of smaller European trials could not confirm such a reduction. The final evaluation of the larger Dutch-Belgian NELSON trial and five other European trials are expected within the next 1-2 years. The results of the completed rounds of screening in all these studies indicate that the margin between a positive and a negative benefit-to-harm balance will be narrow. In such a scenario it will be crucial to optimize the definition of the target population for screening as a high-risk group for lung cancer, the quality of screening in terms of high sensitivity and specificity as well as high quality treatment and an effective ongoing control of program quality. Not all healthcare systems are suitable to fulfill these prerequisites.