Targeted Follow-up of Incidental Lung Nodules: Will the New Nodules in Unscanned Regions Be Missed?

Objective: Targeted computed tomography (TCT) scans a limited part or those parts of the lung with nodules that require follow-up. In order to apply targeted tomography safely, it is important to know the frequency of newly appearing nodules in unscanned regions of lung. We aimed to evaluate the frequency and importance of new pulmonary nodules that appear in patients followed-up for nodules according to Fleischner society guidelines. Methods: A total of 117 patients (women: 54; men: 63; mean age: 55±14 years; range: 30-88 years) who were followed-up for 265 lung nodules were included in this study. The inclusion criteria was presence of at least 1 nodule that was followed-up for at least 6 months with CT. Patients with calcified nodules or known malignancy during initial CT were excluded. Results: The median follow-up time was 22 months (range: 6-80 months) and the median number of follow-up CT scans was 2 (range: 1-5). New nodules appeared only in 6% (7/117) of the patients, of which 5 had nodules that disappeared or decreased in size during follow-up. Conclusion: For patients who were followed-up for pulmonary nodules, the frequency of new nodule formation was low. This should encourage the use of TCT for nodule follow-up. With an appropriate TCT follow-up schedule, patients will receive reasonably low radiation levels without affecting their management.