非游离前列腺特异性抗原密度在前列腺癌筛查中的价值

Value of non-free prostate specific antigen density in screening of prostate cancer

目的探讨非游离前列腺特异性抗原密度(nfPSAd)在前列腺癌(PCa)筛查中的价值。方法回顾分析中国医科大学绍兴医院2016年1月至2020年12月行前列腺穿刺患者373例(PCa 111例,良性前列腺增生262例)的临床资料。根据前列腺体积(PV)、总前列腺特异性抗原(tPSA)、游离前列腺特异性抗原(fPSA),计算nfPSAd。采用ROC曲线分析得出nfPSAd诊断PCa的最佳截断值、约登指数、灵敏度、特异度、诊断符合率,并与另3项指标[tPSA、PSAd、游离比总前列腺特异性抗原(f/tPSA)]进行比较。根据前列腺特异性抗原(PSA)值将患者分为3组:PSA<4 ng/ml组29例、PSA 4~10 ng/ml组190例、PSA>10 ng/ml组154例。根据PV将患者分为PV<50 ml组211例和PV≥50 ml组162例。结果nfPSAd的AUC为0.814,最佳截断值为0.21 ng/ml2,约登指数为0.495,灵敏度为0.667,特异度为0.828,诊断符合率为78.02%,其灵敏度较低,但特异度、约登指数及诊断符合率均在所有指标中最高。PSA<4 ng/ml组、PSA 4~10 ng/ml组、PSA>10 ng/ml组,nfPSAd的AUC、特异度、诊断符合率分别是0.519、1.000、93.10%,0.751、0.913、78.94%,0.823、0.628、74.03%,在PSA>4 ng/ml时,特异度、诊断符合率及AUC均较好。PV≥50 ml时nfPSAd的AUC、特异度与诊断符合率分别为0.667、0.930、85.80%,AUC、特异度与诊断符合率均较好。结论当nfPSAd最佳截断值为0.21 ng/ml2时,其对于前列腺活检的预测准确性优于tPSA、PSAd、f/tPSA。当PSA>4 ng/ml时,nfPSAd是诊断PCa的效果较好。同时在大体积(≥50 ml)PCa筛查中,nfPSAd也是个有价值的指标。

Objective To explore the value of non-free prostate specific antigen density(nfPSAd)in screening of prostate cancer.Methods The results of prostate biopsy of 373 patients in Shaoxing Hospital of China Medical University from January 2016 to December 2020 were retrospectively analyzed,including 111 cases of prostate cancer and 262 cases of benign prostatic hyperplasia.The nfPSAd was calculated according to prostate volume(PV),total PSA(tPSA)and free PSA(fPSA).The ROC curve of nfPSAd was generated with IBM SPSS statistics 26 software,and the best critical value of nfPSAd in the diagnosis of prostate cancer was obtained.The Jordan index,sensitivity,specificity and diagnostic consistence rate were obtained by chi square test.According to tPSA value the patients were divided into three groups:<4 ng/ml,4-10 ng/ml and PSA>10 ng/ml,according to PV value the patients were divided into<50 ml group and≥50 ml group.Results The area under the ROC curve(AUC)of nfPSAd was 0.814,the the best critical value was 0.21 ng/ml2,the Youden index was 0.495,the sensitivity was 0.667,the specificity was 0.828,and the diagnostic consistence rate was 78.02%,which were higher than those of tPSA and fPSA except sensitivity.For patients with tPSA of<4 ng/ml,4-10 ng/ml or>10 ng/ml,the AUC,specificity and diagnostic consistence rates of nfPSAd were 0.519,1.000,93.10%,0.751,0.913,78.94%,and 0.823,0.628,74.03%.For patients with PV≥50 ml,the AUC,specificity and diagnostic consistence rate of nfPSAd were 0.667,0.930 and 85.80%.Conclusion The prediction accuracy of nfPSAd for prostate cancer is better than that tPSA,PSAd and f/tPSA,when PSA>4 ng/ml,nfPSAd is the best index for the diagnosis of prostate cancer,particularly for large prostate(PV≥50 ml).