Early detection of lung cancer using computed tomography among patients with chronic obstructive pulmonary disease

Abstract

Chest computed tomography (CT) scan may improve lung cancer detection at early stages in high risk populations. To assess the diagnostic performance of chest CT in early lung cancer detection in patients with chronic obstructive pulmonary disease (COPD). One hundred sixty one patients aged 50 to 80 years, active or former smokers of 15 or more pack-years and with COPD were enrolled. They underwent annual respiratory functional assessment and chest computed tomography for three years and were followed for five years. Chest CT allowed the detection of lung cancer in nine patients (diagnostic yield: 5.6%). Three cases were detected in the initial CT and six cases in follow-up scans. Most patients were in early stages of the disease (6 stage Ia and 1 stage Ib). Two patients were diagnosed at advanced stages of the disease and died due to complications of cancer. Two thirds of patients had nonspecific pulmonary nodules on the initial chest CT scan (100 patients, 62%). Seventy four percent had less than three nodules and were of less than 5 mm of diameter in 57%. In 92% of cases, these were false positive findings. In the follow-up chest CT, lung nodules were detected in two thirds of patients and 94% of cases corresponded to false positive findings. Chest CT scans may detect lung cancer at earlier stages in COPD patients.