BRONCHIAL CARCINOID TUMOUR
A 63 year old woman developed a cough with haemoptysis. X-ray revealed right middle lobe collapse, and a pneumonectomy was performed.
The right lung has been sliced longitudinally and both cut surfaces are displayed. A pale nodular tumour projects from the orifice of the middle lobe bronchus. The same tumour is seen in the other half of the specimen as a well circumscribed oval pale brown lesion approx. 2 x 3 cm. in diameter. The middle lobe is collapsed and consolidated and has the yellow flecks typical of a lipid pneumonia. Histologically the tumour was a bronchial carcinoid.
Bronchial carcinoid tumours are slow-growing tumours with neuro-endocrine differentiation. They sometimes metastasize to the regional lymph nodes and beyond (e.g. to liver). A small proportion of bronchial carcinoids secrete hormonally active polypeptides or vaso-active amines. The secretion of 5-hydroxy-tryptamine may lead to the carcinoid syndrome. The colour of the tumour in this specimen is typical of carcinoids. Bronchial carcinoids usually have a "dumb-bell" shape: there is a nodule of tumour in the lumen of the bronchus, connected by a thin stalk to an area of invasive growth in the adjacent lung. Lipid pneumonia is patchy consolidation of the lung due to the accumulation of lipid in alveoli, usually within foamy macrophages. The lipid may be endogenous or exogenous in origin. Endogenous lipid pneumonia is associated with bronchial obstruction. The lipid is derived from degenerating cells, and includes surfactant. Exogenous lipid pneumonia is due to inhalation of fats and oils. Endogenous lipid pneumonia occasionally occurs in infected collapsed lung tissue distal to a site of occlusion of a major bronchus.