45-year-old female with haemoptysis and pneumonia. X-ray reveals a central coin lesion. Operative specimen.
Macroscopically: round, poorly demarcated tumour, which occludes a bronchus. Secondary bronchiectasis surrounds the tumour, there is mucus retention and post-stenotic (xanthomatous) pneumonia.
- Central parts of lung and/or bronchus
- Tumor with infiltrative growth
- Net-like arranged strands and nests of middle-sized and cuboid or polygonal, few of which polymorphous, relatively monotonous cells.
- Round-oval nuclei
- Few mitoses
- Tender connective tissue rich in capillaries, in some places metaplastic bone formation
- Clusters of tumour cells with brown reaction product (in the given specimen the absent staining is probably an artifact although immunocytochemical reactions in individual tumour cells typically vary in strength))