35 and above, solid nodule, single nodule, <6mm, high risk, <12 months.

ACR Fleischner Society recommendations (MacMahon, et al. Radiology 2017; 284(1): 228-43) suggest the following: Generally no need for follow-up. An optional follow-up chest CT at 12 months could be performed if there is high index of suspicion. If unchanged, no further follow-up is necessary.