Correct!
5. Thoracic CT scan
Of the choices listed, thoracic CT is best. A pneumonia or a lung cancer would certainly have changed in 5 years, either resolving or progressing. Coccidioidomycosis is also unlikely to cause a density which is unchanged over 5 years and the serologies would likely not be unhelpful. Needle biopsy or bronchoscopy might eventually be needed but not until the density is better defined.
A thoracic CT scan was performed (Figure 2).
Figure 2. Thoracic CT scans in soft tissue windows. Representative axial (A-D, upper left) and coronal (E-H, upper right) images. Thoracic axial CT video (lower left) and coronal CT video (lower right).
Based on the presentation and the thoracic CT findings what is the most likely diagnosis? (Click on the correct answer to proceed to the fourth of five pages)