Lung cancer is one of main cause of cancer death in worldwide, characterized of low 5-year survival rate of less than 20%. Pulmonary nodule is considered as the typical imaging manifestation in early stage of lung cancer. The National Lung Screen Trial has demonstrated that the mortality rates could decline greatly, by the utility of low-dose helical computed tomography for screen of pulmonary nodules. Thus, automatic detection, diagnosis and management of pulmonary nodules, play the vital roles in computer-aided lung cancer screening and early intervention.

Inclusion Criteria:

• Subjects with suspicious lung nodules.
• Thin-layer thoracic CT and pathology examination have been performed for suspicious lung nodules.

Exclusion Criteria:

• Subjects with accompanied lesions on CT images that may interfere to lung nodules analysis

This is a single institutional retrospective cohort study of patients within hospitals in Hong Kong, who had undergone thoracic CT for suspicious lung nodules.