Rashid M M, Alam A K M K, Habib A K M K, Rahman H, Hossain A K M S, Salam M A, Rahman S
Department of Urology, Bangabandhu Sheikh Mujib Medical University, Dhaka.
Bangladesh Med Res Counc Bull. 2012 Dec;38(3):90-3. doi: 10.3329/bmrcb.v38i3.14333.
Indications of prostate biopsy are high serum prostate specific antigen (PSA) value and or abnormal digital rectal examination (DRE) findings. Although serum PSA value of 4 ng/ml is the most commonly used threshold for recommending prostate biopsy, significant proportion of men harbor prostate cancer even when their serum PSA values are less than 4.0 ng/ml. Therefore present study was designed to determine the performance status of serum PSA in lower cut-off values. This hospital based prospective study was conducted in the Department of Urology of Bangabandhu Sheikh Mujib Medical University (BSMMU) and Comfort Nursing Home Pvt. Ltd, Dhaka from July 2009 to October 2010. Two hundred six male patients aged over 50 years having lower urinary tract symptoms (LUTS) and serum PSA more than 2.5 ng/ml were prepared for prostate biopsy. Trans rectal ultrasound (TRUS) guided biopsy was done. The test statistics used to analyze the data were descriptive statistics, sensitivity, specificity, positive and negative predictive value, ROC curve. For all analytical tests, the level of significance was set at 0.05 and p < 0.05 was considered significant. In 2.5-4 serum PSA range, 28.26% (13 out of 46) of all malignancy were found, which would be missed if we take cut off value 4. At 2.5 PSA cut-off, Sensitivity 91.3%, Specificity 14.37%, PPV 23.46%, NPV 85.18%, Efficacy 31.55%. At 4 PSA cut-off value, Sensitivity 71.73%, Specificity 46.25%, PPV 27.73%, NPV 85.05%, Efficacy 51.94%. So it can be concluded that, for early diagnosis of prostate cancer cut-off value of serum PSA of 2.5 ng/ml can be recommended as an indication for prostate biopsy.
前列腺活检的指征是血清前列腺特异性抗原（PSA）值升高和/或直肠指检（DRE）结果异常。虽然血清PSA值4 ng/ml是推荐前列腺活检最常用的阈值，但即使血清PSA值低于4.0 ng/ml，仍有相当比例的男性患有前列腺癌。因此，本研究旨在确定较低临界值时血清PSA的性能状况。这项基于医院的前瞻性研究于2009年7月至2010年10月在达卡的班加班杜·谢赫·穆吉布医科大学（BSMMU）泌尿外科和舒适疗养院私人有限公司进行。对206名年龄超过50岁、有下尿路症状（LUTS）且血清PSA超过2.5 ng/ml的男性患者进行前列腺活检准备。采用经直肠超声（TRUS）引导下活检。用于分析数据的检验统计量包括描述性统计、敏感性、特异性、阳性和阴性预测值、ROC曲线。对于所有分析检验，显著性水平设定为0.05，p < 0.05被认为具有显著性。在血清PSA 2.5 - 4的范围内，所有恶性肿瘤中有28.26%（46例中的13例）被发现，如果我们采用临界值4，这些病例将会被漏诊。在PSA临界值为2.5时，敏感性91.3%，特异性14.37%，阳性预测值23.46%，阴性预测值85.18%，效能31.55%。在PSA临界值为4时，敏感性71.73%，特异性46.25%，阳性预测值27.73%，阴性预测值85.05%，效能51.94%。因此可以得出结论，对于前列腺癌的早期诊断，血清PSA临界值2.5 ng/ml可作为前列腺活检的推荐指征。
