Taneja S S, Tran K, Lepor H
Department of Urology, New York University Medical Center, New York, New York 10016, USA.
Urology. 2001 Aug;58(2):222-7. doi: 10.1016/s0090-4295(01)01229-8.
To determine the effect of prostate volume on the specificity of prostate-specific antigen density (PSAD) and PSAD of the transition zone (PSA-TZ) in the detection of prostate cancer.
Between February 1994 and April 1998, transrectal ultrasound-guided prostate needle biopsies were performed in 235 men with serum prostate-specific antigen (PSA) levels between 4.0 and 10.0 ng/mL. The PSAD and PSA-TZ specificities were calculated at 95% sensitivity cutoff levels generated from the whole group, as well as from cohorts stratified by transition zone index or prostate volume.
Statistical significance was noted between the benign (n = 176) and prostate cancer (n = 59) groups for all tested PSA parameters. At 95% sensitivity, PSA-TZ carried a specificity of 37.5% compared with 29.6% for PSAD. When applying a single 95% sensitivity cutoff derived from the entire group to individual volume-stratified cohorts, the specificity decreased to 0% in glands less than 30 g in size. A 95% sensitivity PSA-TZ cutoff generated individually for volume-stratified cohorts of glands less than 30, 30 to 40, and 40 to 60 g resulted in more consistent specificity of 28.2%, 35.2%, and 45.7% for each cohort, respectively.
Unlike whole group-derived cutoffs, the use of volume-specific PSA-TZ cutoffs allows consistently high specificity in all volume-stratified cohorts. The discrepancies in the PSA-TZ and PSAD specificities in published reports are likely due to the application of published cutoffs to populations of differing prostate volumes. The use of volume-specific cutoffs results in reproducible specificity in populations with differing prostate volume distribution, and thereby definitively resolves the differences in PSA-TZ specificity reported in published reports.
确定前列腺体积对前列腺特异性抗原密度（PSAD）及移行区前列腺特异性抗原（PSA-TZ）在前列腺癌检测中特异性的影响。
1994年2月至1998年4月期间，对235名血清前列腺特异性抗原（PSA）水平在4.0至10.0 ng/mL之间的男性进行经直肠超声引导下前列腺穿刺活检。PSAD和PSA-TZ的特异性是根据全组以及按移行区指数或前列腺体积分层的队列在95%敏感性临界值水平计算得出的。
所有检测的PSA参数在良性（n = 176）和前列腺癌（n = 59）组之间均具有统计学意义。在95%敏感性时，PSA-TZ的特异性为37.5%，而PSAD为29.6%。当将从整个组得出的单一95%敏感性临界值应用于按体积分层的各个队列时，前列腺体积小于30 g的腺体特异性降至0%。针对前列腺体积小于30 g、30至40 g以及40至60 g的按体积分层队列分别单独生成的95%敏感性PSA-TZ临界值，每个队列的特异性更一致，分别为28.2%、35.2%和45.7%。
与源自全组的临界值不同，使用特定体积的PSA-TZ临界值可使所有按体积分层的队列始终具有较高的特异性。已发表报告中PSA-TZ和PSAD特异性的差异可能是由于将已发表的临界值应用于前列腺体积不同的人群。使用特定体积的临界值可在前列腺体积分布不同的人群中产生可重复的特异性，从而明确解决已发表报告中报道的PSA-TZ特异性差异问题。
