The study will recruit 10,000 asymptomatic participants between 40 and 74 years old from Shanghai urban population. The 5000 participants in the intervention group will undergo a low-dose CT scan at baseline and one year later, and will be managed according to European volume-based protocol. The 5000 participants in the control group will undergo a low-dose CT scan according to the routine CT protocol and will be managed according to the clinical practice. Epidemiological data will be collected through questionnaires. In the fourth year from baseline, the diagnosis of the three diseases will be collected. The screening performance will be compared between volume-based and standard protocol for managing early-detected lung nodules. The effectiveness of quantitative measurement of CT imaging biomarkers for early detection of lung cancer, COPD and CVD will be evaluated.
The detected lung nodules in the intervention group will be classified into three groups depending on nodule volume: \< 100 mm3 (negative result), 100-300 mm3 (indeterminate result) and \> 300 mm3 (positive result). In case of a negative result, a CT scan after one year is recommended. In case of an indeterminate result, a 3-month follow up CT is recommended at which VDT will be assessed. For short VDT (\< 400 days), the screening result is positive. Long VDT (\> 400 days) is considered a negative screening result. In case of a positive result, referral to a multidisciplinary team is recommended for further investigation. The detected nodules in the control group will be managed according to the recommended cut-off values of diameter from NCCN Clinical Practice Guideline in Oncology for Lung Cancer Screening.
