ABSTRACT
The first description of the tumour was by Melassey, with a multiple nodular form found at autopsy. Adenomatous hyperplasia of alveolar cells, may be a precursor of tumour formation. Electron microscopy studies have indicated a bronchiolar origin from mucus secreting goblet cells, nonciliated Clara cells or ciliated cells. Haemangioendotheliomas have been considered as more benign and intravascular bronchiolo-alveolar tumours as malignant. The term 'Karcinoide' was first used by Oberndorfer to describe a small-intestine tumour, which was less aggressive than a carcinoma. Patients commonly present with haemoptysis, due to the vascular nature of the tumours. Hormonal syndromes, associated with carcinoid lung tumours, are rare, except with large tumours, or following extensive metastasis. Radioactive labelled somatostatin analogues are now being used in some centres for the imaging of carcinoid tumours.
