Jacobsen S J, Klee G G, Lilja H, Wright G L, Oesterling J E
Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota.
Urology. 1995 Mar;45(3):447-53. doi: 10.1016/S0090-4295(99)80014-4.
To understand the comparability of serum prostate-specific antigen (PSA) determinations across assays and storage time.
Serum PSA levels were determined for men aged 40 to 79 years from the clinical subset of the Olmsted County Study of Urinary Symptoms and Health Status Among Men on fresh samples and after a median of 32 months on banked samples, frozen at -70 degrees C. Baseline serum PSA levels were determined by Tandem-R PSA assay. Follow-up levels on the banked samples were determined by the IMx PSA assay and a repeat Tandem-R PSA assay in a different laboratory and by an immunofluorometric PSA assay at another site.
The median serum PSA level determined by Tandem-R assay at baseline was 1.0 ng/mL (25th percentile, 0.6; 75th percentile, 1.7). The distributions of determination made by follow-up Tandem-R, IMx, and immunofluorometric analyses were essentially identical. Overall, the assays were highly correlated. The correlations between the baseline serum PSA determination and repeated Tandem-R, IMx, and immunofluorometric determinations were 0.96, 0.96, and 0.97, respectively (all P < 0.001). The median duration of frozen storage was 32 months (range, 26 to 39 months), and the correlations between baseline and follow-up determinations did not change when stratified by duration of storage.
These data provide important reassurance about the use of serum PSA determinations obtained by different assays, in different laboratories, and in properly stored samples across time.
了解不同检测方法及储存时间下血清前列腺特异性抗原（PSA）测定结果的可比性。
对参与奥姆斯特德县男性泌尿症状与健康状况研究临床亚组的40至79岁男性，在新鲜样本上以及中位储存32个月后的冻存样本（-70℃冷冻）上测定血清PSA水平。基线血清PSA水平通过Tandem-R PSA检测法测定。冻存样本的随访水平通过IMx PSA检测法、在另一个实验室重复进行的Tandem-R PSA检测法以及在另一个地点进行的免疫荧光PSA检测法测定。
基线时通过Tandem-R检测法测定的血清PSA水平中位数为1.0 ng/mL（第25百分位数为0.6；第75百分位数为1.7）。随访时Tandem-R、IMx和免疫荧光分析测定结果的分布基本相同。总体而言，这些检测方法高度相关。基线血清PSA测定结果与重复Tandem-R、IMx和免疫荧光测定结果之间的相关性分别为0.96、0.96和0.97（均P<0.001）。冻存的中位时间为32个月（范围为26至39个月），按储存时间分层时，基线与随访测定结果之间的相关性未发生变化。
这些数据为不同检测方法、在不同实验室以及对妥善储存的样本随时间进行血清PSA测定的应用提供了重要的保证。
