American Board of Internal Medicine (ABIM) Certification Practice Exam

What is the follow-up recommendation for a solitary pulmonary nodule greater than 4 mm and less than or equal to 6 mm with high pretest probability?

1. Initial follow-up CT at 3 to 4 months

2. Initial follow-up CT at 6 to 12 months

3. Immediate imaging study

4. Follow-up CT only if symptomatic

The correct answer is: Initial follow-up CT at 6 to 12 months

The recommendation for a solitary pulmonary nodule measuring greater than 4 mm and less than or equal to 6 mm, particularly when there is a high pretest probability for malignancy, is to conduct an initial follow-up CT scan at 6 to 12 months. This approach is based on guidelines that consider the size of the nodule and the probability of it being cancerous. A nodule of this size in a patient with a high likelihood of lung cancer warrants careful monitoring to detect any changes that could indicate malignancy. Conducting a follow-up CT scan after 6 to 12 months allows for a significant enough timeframe to observe any growth or changes in the nodule, which would help guide further management decisions. Monitoring too early, such as with a CT at 3 to 4 months, may not provide additional useful information and could lead to unnecessary anxiety and additional unnecessary imaging. Immediate imaging studies are typically reserved for cases where there are concerning symptoms or clear indications that immediate intervention is needed. Lastly, only following up with a CT if the patient becomes symptomatic disregards the potential for asymptomatic cancers to develop and grow, which is why surveillance with imaging is crucial in this context.