Detection of carcinoma of the prostate utilizing biochemical observations

This review presents the current status of attempts to identify individuals with a high risk of carcinoma of the prostate by using biochemical, immunochemical, and immunologic studies of body fluids. Blood, urine, and prostatic fluid have been subjected to a variety of analyses in attempts to find alterations that are sufficiently specific and sensitive enough to be useful in the early recognition of patients with a high probability of localized or disseminated carcinoma of the prostate. A variety of immunologic and immunochemical techniques to identify and quantify acid phosphatase of prostatic origin in the serum are currently being explored for this purpose; as yet, none has achieved the specificity-sensitivity relationship necessary for widespread clinical application. Biochemical studies of prostatic fluid have disclosed a reversal of the lactic dehydrogenase (LDH) isoenzyme pattern with a predominance of LDH-V and increased levels of transferrin, complement C₃ and possibly complement C₄ in association with carcinoma of the prostate. The value of these non-specific changes is increased by the probable direct relationship between prostatic epithelial cell metabolism and changes in prostatic fluid composition. These approaches to identify individuals with a high risk of carcinoma of the prostate hold promise; they should be continued and expanded.