Use of age-specific normal ranges for serum prostate-specific antigen
Slovacek, K.J.; Riggs, M.W.; Spiekerman, A.M.; Speights, V.O.
Archives of Pathology and Laboratory Medicine 122(4): 330-332
1998
ISSN/ISBN: 0003-9985 PMID: 9648900 Document Number: 493947
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.