Small solid noncalcified pulmonary nodules detected by screening chest computed tomography

We aimed to determine the outcome of small (<10 mm) solid noncalcified pulmonary nodules detected by chest computed tomography (CT) scans. Reports of low-dose chest CT scans performed from October 2003 to April 2005 at the Seoul National University Hospital Healthcare System Gangnam Center were reviewed to identify patients with solid noncalcified pulmonary nodules smaller than 10 mm. Partly solid and nonsolid nodules or nodules without follow-up imaging within 1 year were excluded. Records were studied to determine if the initial nodules had changed in size. A total of 3478 chest CT examinations were performed, with 232 patients having small noncalcified nodules (6.7%). One hundred and thirty-eight patients met the criteria (104 men and 34 women) and 213 nodules were identified. The median age was 54 years (range 32-80) and at least 86 patients (62%) were at low to intermediate risk for developing lung cancer. The largest nodule was less than 5 mm in diameter in 87 patients (63%) and 5 mm or more in 51 patients (37%). None of the nodules grew and 29 (14%) decreased in size at follow-up CT scans performed within 12 months. When those individuals at low to intermediate risk for lung cancer were included, solid noncalcified subcentimeter nodules were less frequently found in low-dose CT screening and were nearly unchanged in size when a follow-up CT scan was done within 12 months.