Australian Society of CytologyCase of the Month
May 2003 - Answer and Discussion
Invasive carcinoid tumour of the lung
Answer
The bronchial brushings are heavily blood-stained. They include several groups of cells displaying small to medium size nuclei with regular round outlines and granular chromatin. Nucleoli are small or inconspicuous. Scanty to moderate cytoplasm is present. The nuclei are somewhat crowded but appear orderly with no convincing moulding. These features are consistent with carcinoid tumour.
A concurrent bronchial biopsy was performed.
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| H & E | H & E | Synaptophysin | Chromogranin |
The bronchial biopsy shows a well differentiated epithelial malignancy arranged into nests and cords with some areas showing glandular formation. The cells have ample eosinophilic cytoplasm with many of the nuclei being small and containing smudged and speckled chromatin with inconspicuous nucleoli. Adjacent ulceration with ulcer slough is seen. The appearances are those of a well differentiated neuroendocrine (carcinoid) tumour confirmed by immunoperoxidase studies that show strong cytoplasmic staining with chromogranin and synaptophysin.
Discussion
Bronchial carcinoid tumours usually arise in a large bronchus, probably from Kulchitsky cells or their precursors. They are essentially identical to neuroendocrine tumours of other sites. As the tumours are usually covered by intact bronchial mucosa, cells rarely are spontaneously exfoliated. In this case the lesion was ulcerated resulting in high yield of tumour cells in the bronchial brushings.
The cells generally present as sheets, ball-like clusters or rosettes with some single cells. They are small and monotonous, and round to oval.The cytoplasm may be scant to moderate in amount, and is basophilic, delicate and poorly defined. The nuclei are uniform, round and eccentrically placed. The chromatin is variable but usually "salt-and-pepper". Nucleoli are usually small.
Reference:
- De May, R The Art and Science of Cytopathology, ASCP Press 1996
