Two decades of ITALUNG. What we have learned and what is yet to be addressed in lung cancer screening with low dose CT.

The ITALUNG trial started in 2004 and compared lung cancer (LC) and other-causes mortality in 55-69 years-aged smokers and ex-smokers who were randomized to four annual chest low-dose CT (LDCT) or usual care. ITALUNG showed a lower LC and cardiovascular mortality in the screened subjects after 13 years of follow-up, especially in women, and produced many ancillary studies. They included recruitment results of a population-based mimicking approach, development of software for computer aided diagnosis (CAD) and lung nodules volumetry, LDCT assessment of pulmonary emphysema and coronary artery calcifications (CAC) and their relevance to long-term mortality, results of a smoking-cessation intervention, assessment of the radiations dose associated with screening LDCT, and the results of biomarkers assays. Moreover ITALUNG data indicated that screen-detected LCs are mostly already present at baseline LDCT, can present as Lung Cancer associated with Cystic Airspaces, and can be multiple. However, several issues of LC screening are still unaddressed. They include the annual vs biennial pace of LDCT, choice between opportunistic or population-based recruitment and between uni or multi-center screening, implementation of CAD-assisted reading, containment of false positive and negative LDCT results, incorporation of emphysema and CAC quantification in models of personalized LC and mortality risk, validation of ultra-LDCT acquisitions, optimization of the smoking-cessation intervention and prospective validation of the biomarkers.