ABSTRACT
The presence of sex steroid receptors in human carcinomas was first convincingly shown by Jensen and co-workers. Steroid binding proteins present in the blood have various affinities and binding capacities for sex steroids. The various histochemical techniques reported are discussed and compared to what is known regarding the capacity of these procedures to adequately evaluate estrogen receptor (ER) in situ or otherwise. Although the number of grading systems used by authors studying correlation of histologic and nuclear tumor grades with ER status makes comparisons difficult, a definite trend towards a higher incidence of ER positivity in well-differentiated carcinomas as compared to poorly differentiated tumors exists. The availability of well-documented specific biochemical assays for steroid receptors diminishes the importance of trying to predict receptor content utilizing histologic parameters of questionable predictive value. Several investigators have used immunocytochemical methods with antibody directed against the sex steroid in attempts to localize ER on frozen sections or in fresh tumor cells.
