Crawford E D, Leewansangtong S, Goktas S, Holthaus K, Baier M
Division of Urology, University of Colorado Health Sciences Center, Denver 80262, USA.
Prostate. 1999 Mar 1;38(4):296-302. doi: 10.1002/(sici)1097-0045(19990301)38:4<296::aid-pros5>3.0.co;2-p.
The purpose of this study was to examine the diagnostic efficiency of prostate-specific antigen (PSA) and digital rectal examination (DRE) testing when using either 4.0 ng/ml or an age-specific reference range (ASRR) as an abnormal cutoff PSA value.
Between 1992-1995, 116,073 men, aged 40-79 years, were screened during Prostate Cancer Awareness Week. When using a 4.0-ng/ml cutoff PSA value, 22,014 had either an abnormal PSA, an abnormal DRE, or both. When using an ASRR cutoff PSA value, 17,561 had either an abnormal PSA, an abnormal DRE, or both. The positive predictive value (PPV), sensitivity, and specificity of PSA, DRE, and combined PSA and DRE tests were evaluated.
When using a 4.0-ng/ml cutoff PSA value, the PPVs of abnormal PSA alone, abnormal DRE alone, and combined abnormal PSA and DRE tests were 27.7%, 17.7%, and 56.0%, respectively. Sensitivities were 34.9%, 27.1%, and 38.0%, respectively. Specificities were 63.1%, 49.0%, and 87.9%, respectively. When using an ASRR cutoff PSA value, the PPVs of each category were 31.8%, 20.8%, and 63.7%, respectively. Sensitivities were 27.1%, 41.0%, and 31.8%, respectively. Specificities were 75.0%, 32.8%, and 92.2%, respectively. The PPVs of the PSA test were higher than those of the DRE. The PPVs of combined tests were highest when using either a 4.0-ng/ml cutoff PSA value or an ASRR cutoff PSA value (all P < 0.001). When using an ASRR, the PPVs of PSA, DRE, and combined tests were higher than those when using a 4.0-ng/ml without statistical significance (all P > 0.05). Sensitivity of PSA when using an ASRR was lower than when using 4.0 ng/ml.
Significantly higher PPVs indicated that utilizing both a PSA test and a DRE is most effective in screening for the early detection of prostate cancer. Although higher PPVs when using an ASRR cutoff PSA value suggested fewer unnecessary biopsies, lower sensitivities resulted in fewer cancers detected. Thus, we recommend that the combination of a PSA test with a cutoff value of 4.0 ng/ml and a DRE should continue to be utilized in the screening programs.
本研究的目的是在将4.0 ng/ml或年龄特异性参考范围（ASRR）用作异常临界值前列腺特异性抗原（PSA）值时，检验PSA和直肠指检（DRE）检测的诊断效率。
在1992年至1995年期间，在前列腺癌宣传周对116,073名年龄在40至79岁之间的男性进行了筛查。当使用4.0 ng/ml的临界PSA值时，22,014人PSA异常、DRE异常或两者均异常。当使用ASRR临界PSA值时，17,561人PSA异常、DRE异常或两者均异常。评估了PSA、DRE以及PSA和DRE联合检测的阳性预测值（PPV）、敏感性和特异性。
当使用4.0 ng/ml的临界PSA值时，单独PSA异常、单独DRE异常以及PSA和DRE联合异常检测的PPV分别为27.7%、17.7%和56.0%。敏感性分别为34.9%、27.1%和38.0%。特异性分别为63.1%、49.0%和87.9%。当使用ASRR临界PSA值时，各分类的PPV分别为31.8%、20.8%和63.7%。敏感性分别为27.1%、41.0%和31.8%。特异性分别为75.0%、32.8%和92.2%。PSA检测的PPV高于DRE检测的PPV。当使用4.0 ng/ml的临界PSA值或ASRR临界PSA值时，联合检测的PPV最高（所有P < 0.001）。当使用ASRR时，PSA、DRE和联合检测的PPV高于使用4.0 ng/ml时，但无统计学意义（所有P > 0.05）。使用ASRR时PSA的敏感性低于使用4.0 ng/ml时。
显著更高的PPV表明，同时使用PSA检测和DRE在筛查前列腺癌早期检测中最有效。尽管使用ASRR临界PSA值时更高的PPV表明不必要的活检更少，但更低的敏感性导致检测到的癌症更少。因此，我们建议在筛查项目中继续使用临界值为4.0 ng/ml的PSA检测与DRE相结合的方法。
