The serum PSA concentration is directly correlated with patient age and prostatic volume. thus, rather than rely rely on a single reference range for mean of all age group, it is more appropriate to have age-specific reference ranges. We define
the
cancer-free population as men with a PSA less than or equal to 4.0ng/ml and nonsuspicious digital rectal examination, and those with an abnormality in either parameter with a nonmalignant prostate biopsy.
A total of 905 men was recruted for a prostate cancer detection study using serum PSA and digital rectal examination, of whom 869 fulfilled our criterial of cancer-free. The upper limits for PSA (mean+2 standard deviations) by age were 2.89ng/ml
in
the
40 to 49-year group, 4.67ng/ml in the 50 to 59-year group, 5.49ng/ml in the 60 to 69-year group and 6.48ng/ml in the 70 to 79-year group. It is the purpose of our study to know that how accurate our definition of normal as evidenced by a lack of
cancer
in men with a normal digital rectal examination and PSA between 4.0 and the derived upper limit of normal is. The apparent accuracy of these new limits is strong in the 50 to 69-year group but it declines in the next decade. The data support
further
attempts at using PSA, age and digital rectal examination to establish selection criterial for prostate biopsy with adequate specificity.
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