游离前列腺特异性抗原百分比、总前列腺特异性抗原、年龄和腺体体积在前列腺癌检测中的相关性。

Association of free PSA percent, total PSA, age, and gland volume in the detection of prostate cancer.

作者信息

Mettlin C, Chesley A E, Murphy G P, Bartsch G, Toi A, Bahnson R, Church P

机构信息

Roswell Park Cancer Institute, Buffalo, New York 14263-0001, USA.

出版信息

Prostate. 1999 May 15;39(3):153-8. doi: 10.1002/(sici)1097-0045(19990515)39:3<153::aid-pros2>3.0.co;2-v.

DOI:10.1002/(sici)1097-0045(19990515)39:3<153::aid-pros2>3.0.co;2-v

PMID:10334103

Abstract

BACKGROUND

Measurement of the free fraction of total prostate-specific antigen (fPSA%) has been proposed as a useful addition to total PSA for the detection of prostate cancer.

METHODS

We assessed the performance of fPSA% in differentiating men with prostate cancer from men without cancer in a group of 1,709 subjects studied in five institutions.

RESULTS

On the basis of PSA testing, digital rectal examination, and ultrasound examination conducted at one or more visits, 229 cancers were diagnosed. The mean fPSA% in men with cancer was 9.1% compared to 18.9% in men without cancer. The fPSA% varied by age, with men under 60 having a mean fPSA of 13.9% compared to 17.5% in men 60-69 years old and 19.8% in men over age 70. Significant associations of fPSA% with gland volume and PSA level were also observed. The sensitivity, specificity, and positive predictive value of different fPSA% cutoff levels were assessed in 513 men who underwent sextant biopsy. Sensitivity of 85.4%, 32.1% specificity, and a 39.2% positive predictive value were observed using an fPSA cutoff of 15% in men with PSA in the 4.0-9.9 ng/ml range. Sensitivity of 96.9%, 12.3% specificity, and a 36.2% positive predictive value were observed using an fPSA cutoff of 20% in the same men. If 15% fPSA had been used as a biopsy criterion in men with PSA of 4.0-9.9 ng/ml, the number of biopsies performed could have been reduced by 21.2%, with a concomitant reduction in cancer detection of 14.6%. Using a 20% fPSA criterion, biopsies would have been reduced 12.7%, with a 3.1% reduction in cancer detection.

CONCLUSIONS

These results provide some evidence that the detection of prostate cancer is enhanced by measuring fPSA% in addition to the established measure of total PSA level. Further research is needed to identify other markers that have better sensitivity and specificity.

摘要

背景

总前列腺特异性抗原游离分数（fPSA%）的检测已被提议作为总PSA检测的有益补充，用于前列腺癌的检测。

方法

我们在五个机构研究的1709名受试者中，评估了fPSA%在区分前列腺癌患者和非癌患者方面的性能。

结果

基于一次或多次就诊时进行的PSA检测、直肠指检和超声检查，共诊断出229例癌症。癌症患者的平均fPSA%为9.1%，而非癌症患者为18.9%。fPSA%随年龄变化，60岁以下男性的平均fPSA为13.9%，60 - 69岁男性为17.5%，70岁以上男性为19.8%。还观察到fPSA%与腺体体积和PSA水平之间存在显著关联。在513名接受六分区活检的男性中，评估了不同fPSA%临界值水平的敏感性、特异性和阳性预测值。在PSA为4.0 - 9.9 ng/ml的男性中，使用15%的fPSA临界值时，敏感性为85.4%，特异性为32.1%，阳性预测值为39.2%。在同一组男性中，使用20%的fPSA临界值时，敏感性为96.9%，特异性为12.3%，阳性预测值为36.2%。如果将15%的fPSA用作PSA为4.0 - 9.9 ng/ml男性的活检标准，活检次数可减少21.2%，同时癌症检测率降低14.6%。使用20%的fPSA标准，活检次数将减少12.7%，癌症检测率降低3.1%。