利用ROC曲线评价前列腺癌诊断指标的诊断价值

Evaluate the diagnostic value of prostatic carcinoma diagnosis index by ROC curve

目的探讨血清总前列腺特异性抗原(total prostate specific antigen,tPSA)、游离PSA(free PSA,fPSA)及其比值(fPSA/tPSA)在诊断前列腺癌(prostatic carcinoma,PCA)中的价值。方法收集2008年1月至2012年12月于我院就诊的23例PCA患者,246例良性前列腺增生(benign prostate hyperplasia,BPH)患者,及85例同期健康体检者,用化学发光法检测受试者血清中的tPSA、fPSA及其比值fPSA/tPSA,通过受试者工作特征(receiver operating characteristic,ROC)曲线分析各指标用于诊断PCA的诊断效能。结果 tPSA、fPSA检测结果三组间比较,差异均有统计学意义(P均<0.01),而fPSA/tPSA三组间比较,差异无统计学意义(P>0.05)。PCA组tPSA和fPSA检测水平均明显高于BPH组和健康对照组,差异均有统计学意义(P均<0.05)。BPH组tPSA和fPSA检测水平均高于健康对照组,差异均有统计学意义(P均<0.05)。经ROC曲线分析,tPSA、fPSA、tPSA+fPSA以及fPSA/tPSA用于诊断PCA的ROC曲线下面积分别为:0.995、0.991、0.995、0.362。tPSA、fPSA诊断PCA的cutoff值分别为23.09μg/L、4.05μg/L,对应的灵敏度和特异性分别为100.0%、96.1%和100.0%、94.3%。结论 tPSA、fPSA对于诊断PCA有较好的诊断效能,其cutoff值分别为23.09μg/L、4.05μg/L。

Objective To investigate the diagnostic value of total prostate specific antigen （tPSA）, free PSA （fPSA） and fPSA/tPSA in prostatic carcinoma （PCA） diagnosis. Methods 23 cases PCA patients, 246 cases benign prostate hyperplasia （BPH） patients and 85 cases healthy controls in our hospital from Jan-uary 2008 to December 2012 were collected. The levels of tPSA , fPSA and fPSA/tPSA were detected by chemiluminescence analytic method. The diagnosis efficiency of each index in diagnosing PCA were analyzed by receiver operating characteristic（ROC） curve. Results There were statistical significance in the difference of tPSA and fPSA levels among three group（Pall〈0.01）, except fPSA/tPSA（P〉0.05）. The levels of tPSA and fPSA in PCA group were all higher than those of BPH group and control group , and the differences all had sta-tistical significance （Pall〈0.05）. The levels of tPSA and fPSA in BPH group were all higher than those of con-trol group, and the differences all had statistical significance （Pall〈0.05）. The area under ROC of tPSA, fP-SA, tPSA＋fPSA and fPSA/tPSA in diagnosing PCA were 0.995, 0.991, 0.995 and 0.362, respectively. The cutoff value of tPSA and fPSA in diagnosing PCA were 23.09μg/L and 4.05μg/L, and the corresponding sen-sitivity and specificity were 100.0%, 96.1%and 100.0%, 94.3%. Conclusion tPSA and fPSA have better diagnosis efficiency in PCA diagnosing, and their cutoff value were 23.09μg/L and 4.05μg/L, respectively.