PSA is the most important of all tumor markers because it has significant a
pplications in all aspects of the management of men with prostatic disease.
Certainly, the most important utilization of PSA is for early detection of
this most ubiquitous of all human neoplasms.
In this article the authors describe the molecular forms of PSA and their c
haracteristics, the factors influencing values of serum concentration of PS
A, the problems of screening, and particularly the possibility to use PSA f
or detection of prostate carcinoma. A big problem in prostate carcinoma det
ection is the low specificity of PSA at the concentrations between 4-10 ng/
ml, the so-called diagnostic gray zone, where the incidence of prostate car
cinoma is only 25%, The authors evaluate the methods which make it possible
to increase the sensitivity and/or specificity of PSA detection, such as P
SA density, PSA density of the transition zone, PSA velocity, PSA doubling
time, age-specific PSA, free PSA and, prospectively, the use of the RT-PCR