Fifty years of development in the endocrinology laboratory.

The hormone assay laboratory has seen incredible changes over the last 50 years. In this historical review, we describe how the evolution of fundamental concepts in endocrinology and in hormone assay technology have faceted the laboratory as we know it today. The discovery of neurohormones, hormone receptors and the evolution of the concept of free hormones had a very significant impact on our understanding of the mechanisms of hormone action in health and disease and therefore on how physicians currently prescribe endocrine tests. In the analytical field, modern hormone assays rapidly replaced crude colorimetric methods and bioassays. Starting with the pioneering work of Yalow and Berson, hormone assays have gradually evolved through improvements in all aspects of assay design. This is best exemplified by the evolution of thyroid and parathyroid hormone assays. After reviewing some of the limitations of actual hormone immunoassays, we present some reflections on what the future of the hormone laboratory may look like considering all the developments in automation, point-of-care testing, molecular biology and array technologies.