Use of age-specific normal ranges for serum prostate-specific antigen.

BACKGROUND

The traditional normal range for prostate-specific antigen has been 0.0 to 4.0 ng/mL. Two different age-specific normal ranges have been proposed, one by Oesterling et al and the other generated by the Prostate Cancer Awareness Week experience.

METHODS

We studied 213 consecutive cases of biopsy-proven prostate adenocarcinoma to evaluate age-specific normal ranges for prostate-specific antigen. We examined each patient's age, stage of disease, and serum concentration of prostate-specific antigen at the time of diagnosis. The three normal ranges were applied to each case.

RESULTS

The patients ranged in age from 45 to 87 years. At all stages of disease, more patients had elevated serum prostate-specific antigen values using the traditional normal range as opposed to either age-specific normal range. These discrepancies were most obvious for stage II disease, in which 93 of 119 cases (78%) were elevated according to the traditional normal range versus 78 of 119 cases (66%) according to the Oesterling et al range and 80 of 119 cases (67%) according to the range defined during Prostate Cancer Awareness Week. For patients aged 40 to 59 years, all three normal ranges provided identical results (18 of 22 [82%] cancers detected).

CONCLUSIONS

Use of either age-specific normal range would have missed more than 10% of stage II prostate adenocarcinomas in patients over the age of 60 years. This indicates that caution should be exercised when applying age-adjusted normal ranges for serum concentrations of prostate-specific antigen in patients of that age group.