无前列腺疾病男性fPSA百分比正常参考值范围分析

目的 研究年龄对男性游离前列腺特异性抗原(free prostate specific antigen, fPSA)百分比的影响及fPSA百分比与前列腺癌病理分级及临床分期的关系,并探讨适合于中国人的fPSA百分比参考值范围.方法 选择无前列腺疾病男性679例,按年龄不同分为5组,测定血清PSA、fPSA并计算fPSA百分比,研究年龄与PSA、fPSA、fPSA百分比相关性.另选34例经病理证实的前列腺癌(PCa)患者,研究fPSA百分比与前列腺癌病理分级及临床分期的关系.结合无前列腺疾病男性的fPSA百分比,确定适合于中国人的fPSA百分比参考值范围. 结果 PSA、fPSA与年龄呈正相关(r值分别为0.608和0.534,P＜0.001),fPSA百分比与年龄无关.fPSA百分比与前列腺癌病理分级及临床分期相关(r值分别为0.427和-0.332,P＜0.05).以无前列腺疾病男性第5百分位上的fPSA百分比值(13.6%)及试剂盒上与多数文献报告fPSA百分比值为参考,选取10%、15%及20% 3个值作为鉴别值.当参考值范围为≥15%时,诊断前列腺癌的敏感性为94.1%,特异性高达89.7%.如参考值范围为≥10%时,特异性虽为 97.4%,但敏感性仅为70.6%.如参考值范围为≥20%时,敏感性亦为94.1%,但有253例无前列腺疾病男性为假阳性,特异性仅为62.8%.适合于中国人的fPSA百分比正常参考值范围为≥15%. 结论 fPSA百分比不受年龄因素影响,临床价值优于PSA.随着前列腺癌患者fPSA百分比降低,其病理分化程度降低,临床分期增加,恶性程度增高.适合于中国人的fPSA百分比正常参考值范围为≥15%.

Analysis of Reference Range Responsible to Normal Percent Value of Free Prostate Specific Antigen from Men without Prostate Disease

OBJECTIVE: To study the effect of age on the percent value for free prostate specific antigen (fPSA) from men, and the relationships between the percent fPSA and the pathological grade or the clinical stage of prostate cancer (PCa), and also to determine appropriate reference value range for Chinese men. METHODS: A total of 713 participants were enrolled into the study, with the serum PSA, fPSA measured and the percent fPSA calculated. Out of 713, 679 men without prostate disease were divided into 5 groups by age, and then the relationships were studied between man age and PSA, fPSA or percent fPSA, respectively. The relationships between pathological grade or clinical stage and percent fPSA were also studied in the rest 34 participants suffering from PCa. With the help of the related data of men without prostate disease, the appropriate reference value range was established for Chinese men. RESULTS: PSA and fPSA were positive correlated with age (r was 0.608 and 0.534 respectively, P < 0.001), while there was no significant correlation between age and percent fPSA. The percent fPSA was also correlated with pathological grade, clinical stage of Pca (r was 0.427 and -0.332 respectively, P < 0.05). According to the data of our early studies and the reference value range of percent fPSA given by the test kit and the previously reported medical references, the data of 10%, 15% and 20% were selected as the percent fPSA threshold values to distinguish PCa or health men without prostate disease. The sensitivity of diagnosing PCa was 94.1% and the specificity was 89.7% when the reference range was more than 15%. When the reference range was more than 10%, the sensitivity of diagnosing PCa was 70.6% and the specificity was 97.4%. When the reference range was more than 20%, the sensitivity also was 94.1%, but the specificity merely was 62. 8%. The reference range of percent fPSA for Chinese men was > or = 15%. CONCLUSION: The percent fPSA may be more useful than PSA in the detection of prostate cancer. With the percent fPSA dropping down, the pathological differentiating grade of PCa appears lower, but the clinical stage is high, the malignant degree is also increased. The reference range of > or = 15% percent fPSA is more appropriate threshold value for diagnosing the prostate cancer in Chinese man population.