Lung cancer screening with low-dose CT: a world-wide view.

Lung cancer is the leading cause of cancer death worldwide, comprising almost 20% of all cancer deaths. The concept of screening for lung cancer using low-dose computed tomography (LDCT) dates back almost three decades. This paper reviews the randomized controlled trials and demonstration projects carried out world-wide on LDCT lung cancer screening. Most research has been carried out in North America, Europe and East Asia, regions where lung cancer mortality rates are generally the highest. There are currently no organized national or regional lung cancer screening programs with LDCT. A number of challenges exist to implementing such programs, including the fact that LDCT lung cancer screening generally targets only high risk ever-smokers, in contrast to screening programs for other cancers such as breast, cervical and colorectal, which target entire populations based only on age and sex. While tobacco control remains the most important tool in the long-term to decrease morbidity and mortality from lung cancer, LDCT screening, appropriately carried out, has the potential to modestly decrease lung cancer death rates for those countries whose overall resources and health care infrastructure are adequate for the task.