Routine analysis of multiple steroid receptors in human breast cancer.--I--Technological features.

The technological features of multiple and simultaneous assays of steroid receptors (estrogen and progestagens) have been considered in human mammary carcinomas. Most of the parameters involved in the accuracy and the fiability of S-R determination have been investigated : the stability of S-R proteins (collection and storage of sample, cytosol preparation and buffer components, endogenous steroid problem), the specificity and precise quantitation of the binding (conditions of incubations, use of steroid analogs, dextran-coated charcoal method and treatment of binding data by the Scatchard analysis), the identification of the binding (vertical sucrose density gradients) and the interferences in DCC assays. The routinely adopted protocol has been experienced in 650 cases of S-R assay. It is concluded that when performed under appropriate and properly controlled conditions and even in a small sample, multiple S-R assay could result in a precise quantitation and identification of the pathological state of the S-R system in a tumor at time of surgery. Considered with regards to actual knowledges in cell biology, that is of importance and could provide even more information about therapeutic guidance.