Erol Bulent, Gulpinar Murat Tolga, Bozdogan Gurdal, Ozkanli Seyma, Onem Kadir, Mungan Görkem, Bektas Sibel, Tokgoz Husnu, Akduman Bulent, Mungan Aydin
Department of Urology, Faculty of Medicine, Istanbul Medeniyet University, Istanbul, Turkey.
Department of Urology, Faculty of Medicine, Istanbul Medeniyet University, Istanbul, Turkey.
Kaohsiung J Med Sci. 2014 Nov;30(11):545-50. doi: 10.1016/j.kjms.2014.03.008. Epub 2014 Apr 20.
We investigated an optimal cutoff level of free/total PSA ratios (f/t PSA) in predicting prostate cancer in different age groups, focusing on the avoidance of unnecessary prostate biopsies. A total of 4955 men were enrolled into the study. Serum tPSA, fPSA, and f/t PSA ratios were determined for the study population. All males who had suspicious digital rectal examination and tPSA > 4 ng/mL underwent transrectal ultrasonography-guided prostate biopsy. Receiver operating characteristic (ROC) curves for each group were generated by plotting the sensitivity versus 1-specificity for the f/t PSA ratio. The sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were obtained using various f/t PSA ratio cutoffs for different age groups. There were 657 patients with a PSA level of 4-10 ng/mL. According to sensitivity and specificity f/t% PSA cutoff points were determined to be 10%, 15%, 15%, and 10% in 50-59 years, 60-69 years, >70 years, and all ages categories, respectively, in patients with initial PSA level of 4-10 ng/mL. f/t PSA ratio had an area under the curve (AUC) value of 0.81 (95% confidence level: 0.80-0.82) for all age groups in detecting prostate cancer. f/t PSA ratio has an AUC value of 0.669 (0.632-0.705) in detecting prostate cancer among patients with a PSA level of 4-10 ng/mL. Ten percent of f/t PSA ratio had the highest specificity with PLR and 30% f/t PSA ratio had the highest sensitivity with lower NLR in the all-age categories. The current study shows that the use of f/t PSA ratio in patients with PSA levels of 4-10 ng/mL should enhance the specificity of PSA screening and decrease the number of unnecessary biopsies. The age-related changes warrant further investigation in a large, multicentric, and multinational population to improve the clinical use of f/t PSA cutoffs.
我们研究了游离/总前列腺特异性抗原比值（f/t PSA）在预测不同年龄组前列腺癌中的最佳临界值，重点是避免不必要的前列腺活检。共有4955名男性纳入本研究。测定了研究人群的血清总前列腺特异性抗原（tPSA）、游离前列腺特异性抗原（fPSA）和f/t PSA比值。所有直肠指检可疑且tPSA>4 ng/mL的男性均接受经直肠超声引导下的前列腺活检。通过绘制f/t PSA比值的敏感度与1-特异度生成每组的受试者工作特征（ROC）曲线。使用不同年龄组的各种f/t PSA比值临界值获得敏感度、特异度、阳性似然比（PLR）和阴性似然比（NLR）。有657例患者的PSA水平为4-10 ng/mL。根据敏感度和特异度，初始PSA水平为4-10 ng/mL的患者中，50-59岁、60-69岁、>70岁和所有年龄组的f/t% PSA临界值分别确定为10%、15%、15%和10%。在所有年龄组中，f/t PSA比值在检测前列腺癌时曲线下面积（AUC）值为0.8（95%置信区间：0.80-0.82）。在PSA水平为4-10 ng/mL的患者中，f/t PSA比值在检测前列腺癌时AUC值为0.669（0.632-0.705）。在所有年龄组中，10%的f/t PSA比值具有最高特异度和PLR，30%的f/t PSA比值具有最高敏感度和较低的NLR。当前研究表明，在PSA水平为4-10 ng/mL的患者中使用f/t PSA比值应可提高PSA筛查的特异度并减少不必要活检的数量。年龄相关变化值得在大型、多中心和多国人群中进一步研究，以改善f/t PSA临界值的临床应用。
