Role of biological markers and probes in lung carcinomas.

Bronchial carcinomas are frequently associated with ectopic secretion of hormones which may be responsible for paraneoplastic syndromes. In non small cells carcinomas, serum calcitonin levels may be raised. Hypercalcaemia can be found in squamous carcinomas and secretion of hCG (responsible for gynaecomastia) in large cells carcinomas. In small carcinomas, many hormones (ACTH, MSH, ADH, calcitonin) can be produced; however, their serial measurements as well as that of the carcino-embryonic antigen add nothing to the information available with standard staging investigations. More recent studies have identified three protein products: the BB-isoenzyme of creatine kinase, bombesin and neurone-specific enolase. The latter seems a promising marker to follow up the course of the disease.