Histochemical observation of R 1881-binding protein in human prostatic cancer.

Abstract

A conjugate of fluorescein isothiocyanate and bovine serum albumin bound with R 1881-3-carboxymethyloxime was used to visualize the location of androphilic proteins in tissues from patients with prostatic cancer. The fluorescence was located in the carcinoma cells but not in the stroma. Although intensity of the staining was varied in fluorescence-positive cases, almost all carcinoma cells were stained. On the contrary, positively stained cells were scarcely observed in fluorescence-negative cancer. Among 46 cases of untreated prostatic cancer examined, 76% were fluorescence-positive. 7 cases out of 9 who had relapsed from endocrine therapy showed negative fluorescence. It was concluded that the fluorescence in the tissue sections of the untreated prostatic cancer were well correlated with the histologic grade, and that fluorescence-positive cases had responded well to the endocrine therapy, as judged 6 months after the start of treatment.