MACROSCOPIC DESCRIPTION:
Left upper lobe": A lung lobe 185x110x55mm with bronchovascular remnants up to 25mm. Arising in the hilum and involving the bronchus is a rubbery tan-pink tumour 21x20x19mm. The tumour is 6mm from the bronchovascular margins and 3mm from the hilar margin. 26mm from the tumour and 1mm from the pleura there is a firm white nodule 6mm. Peripheral to the tumour is an area where the lung shows dilated bronchi up to 12mm in diameter which lie 2mm from the pleura.
MICROSCOPIC DESCRIPTION:
Sections of the lung show a well-demarcated moderately cellular tumour, which invades into a bronchus. The tumour forms cohesive nests, cords and rosettes, surrounded by vascularised stroma. The tumour cells have mildly enlarged round nuclei, granular chromatin, inconspicuous nucleoli and moderate amounts of granular eosinophilic cytoplasm. 1 mitosis per 10 high power field is seen. There is no evidence of necrosis. The visceral pleura is uninvolved. No evidence of lymphovascular invasion is seen. The tumour is completely excised. The bronchial and vascular margins are clear. The tumour is pushing into a hilar lymph node with direct involvement for 3mm. Another benign hilar lymph node is present. The subpleural nodule is a pulmonary hamartoma. There is elongated respiratory type epithelium, being surrounded by nodules of cartilage and myxomatous stroma. The remaining lung parenchyma show a few dilated bronchi but they are not inflamed. The tumour cells are synaptophysin and CD56 positive. The Ki-67 index is about 2%.
COMMENT:
The features are those of typical carcinoid.
Courtesy: Pathology Department, The Royal Melbourne Hospital.