Findings: The PA chest radiograph shows two obvious small nodules in the left middle lung field (A, circle), not present five years earlier (B). In my experience, two nodules close together are usually granulomas. But in this case we have another finding: a subtle bulge in the left hilum (A, arrow), not visible in the previous film, highly suspicious of hilar adenopathy. This changes the diagnostic orientation and makes us think of an active process.

Unenhanced axial CT shows an hourglass-shaped pulmonary lesion (C and D, arrows) that simulated two nodules in the chest radiograph. The lesion enhances after contrast injection and contains a large arterial vessel (E, arrow). Non-enhancing lymph nodes are visible in the left hilum (F, arrow).
Although all three diagnoses offered in the blog can cause hilar adenopathy, the vascularity of the lesion points to a tumor.

PET-CT shows faint uptake of the primary lesion and the hilar lymph nodes (G and H, arrows). A needle biopsy (I, arrow) came back as an atypical small-cell tumor.

The patient was treated with chemotherapy and radiotherapy, with a good response of the primary tumor (J, arrow) and lymph nodes (K, circle).

Final diagnosis: SCLC with hilar metastasis and a good response to QT and RT

Discussion: I just finished reading “The subtle art of not giving a f*ck“ and there is an enlightening (and sadly true) chapter entitled “You are not special”. In this particular case I was feeling special, as I diagnosed a malignant pulmonary fibroma based on a single case seen 20 years ago (see below) because of the similarity of the vascular pattern in the two cases. After 50 years of practice, I forgot a basic principle: common conditions are, well, common. I’m showing this case to remind you that when faced with a diagnostic dilemma you should first consider common options rather than uncommon ones.

To redeem myself, I am showing my only case of fibrous tumor of lung in a 37-year-old woman with hemoptysis. The PA radiograph shows a well-defined paramediastinal nodule (A, arrow). Enhanced coronal and sagittal CT confirms the intrapulmonary location of the nodule, which has a large arterial vessel in the center with an aneurysm at the end (B and C, arrows).

Surgery confirmed a fibrous tumor of the lung.

Two bits of information about fibrous tumor of the lung: It is a very unusual spindle-cell tumor with the same histology as fibrous tumors of pleura, and like them, it has malignant potential. It is usually asymptomatic and is seen as a rounded or ovoid nodule of varying size. Immunohistochemistry is important for the diagnosis.

Follow Dr. Pepe’s pearls of wisdom:

Always consider that what you are seeing is a rare manifestation of a common disease rather than a common manifestation of a rare disease.