Abstract
Tumour markers are defined as substances, measured by laboratory techniques, which are useful in the management of the patient with cancer. In this review the current clinical use and abuse of tumour markers is discussed with a view to outline the status of quality assurance in their performance and to establish the significance of single marker versus multiple marker analysis. The problems of screening are considered. It is emphasized that in order for tumour markers to take their appropriate place in cancer management the following are needed: high throughput automated equipment; new markers and new assays for old markers; reference materials and standards; nomenclature standardization and the introduction and evaluation of quality assurance programs which include proficiency studies. These needs can only be achieved by close cooperation of clinicians, laboratory professionals and the diagnostic industry