University of Colorado, Anschutz Medical Campus, Aurora, Colorado 80045, USA.
J Urol. 2012 Nov;188(5):1726-31. doi: 10.1016/j.juro.2012.07.023. Epub 2012 Sep 19.
The detection of prostate cancer relies primarily on abnormal digital rectal examination or increased serum prostate specific antigen concentration. However, low positive predictive values result in many men with increased prostate specific antigen and/or suspicious digital rectal examination having a negative biopsy. We investigated the value of the PCA3 (prostate cancer gene 3) urine test in predicting the likelihood of diagnosis of cancer before biopsy.
We performed a prospective, community based clinical trial to evaluate PCA3 score before any biopsy. This trial was conducted at 50 urology practices in the United States. Samples were obtained from 1,962 men with increased serum prostate specific antigen (greater than 2.5 ng/ml) and/or abnormal digital rectal examination before transrectal prostate needle biopsy. Study samples (urinary PCA3 and biopsies) were processed and analyzed by a central laboratory. Sensitivity-specificity analyses were conducted.
A total of 1,913 urine samples (97.5%) were adequate for PCA3 testing. Of 802 cases diagnosed with prostate cancer 222 had high grade prostatic intraepithelial neoplasia or atypical small acinar proliferation and were suspicious for cancer, whereas 889 cases were benign. The traditional PCA3 cutoff of 35 reduced the number of false-positives from 1,089 to 249, a 77.1% reduction. However, false-negatives (missed cancers) increased significantly from 17 to 413, an increase of more than 2,300%. Lowering the PCA3 cutoff to 10 reduced the number of false-positives 35.4% and false-negatives only increased 5.6%.
Urinary PCA3 testing in conjunction with prostate specific antigen has the potential to significantly decrease the number of unnecessary prostate biopsies.
前列腺癌的检测主要依赖于异常的直肠指检或前列腺特异性抗原浓度升高。然而，阳性预测值较低导致许多前列腺特异性抗原升高和/或直肠指检可疑的男性进行了阴性活检。我们研究了 PCA3（前列腺癌基因 3）尿液检测在活检前预测癌症诊断可能性的价值。
我们进行了一项前瞻性、基于社区的临床试验，以评估活检前 PCA3 评分。该试验在美国 50 个泌尿科诊所进行。研究对象为 1962 名血清前列腺特异性抗原（大于 2.5ng/ml）升高和/或直肠指检异常的男性，这些患者在接受经直肠前列腺针吸活检前采集了样本。研究样本（尿液 PCA3 和活检）由一个中心实验室进行处理和分析。进行了敏感性-特异性分析。
共有 1913 份尿液样本（97.5%）可用于 PCA3 检测。在 802 例诊断为前列腺癌的病例中，222 例有高级别前列腺上皮内瘤变或不典型小腺泡增生，怀疑为癌症，而 889 例为良性。传统的 PCA3 截断值为 35，将假阳性从 1089 例减少到 249 例，减少了 77.1%。然而，假阴性（漏诊癌症）显著增加，从 17 例增加到 413 例，增加了 2300%以上。将 PCA3 截断值降低到 10 可将假阳性减少 35.4%，而假阴性仅增加 5.6%。
结合前列腺特异性抗原进行尿液 PCA3 检测有可能显著减少不必要的前列腺活检数量。
