多参数MRI对PSA为4~10μg/L前列腺癌的诊断价值分析

目的:探讨联合应用磁共振成像(MRI)-T2WI、DWI和DCE-MRI检查对前列腺特异性抗原(PSA)为4~10μg/L的可疑前列腺癌人群的诊断价值。方法:回顾性分析2014年7月~2016年3月间于我院收治的PSA为4~10μg/L的242例前列腺穿刺患者的临床资料。单因素和多因素Logistic回归分析患者的年龄、体质指数(body mass index,BMI)、tPSA、游离与总PSA比值(f/tPSA)、前列腺体积(prostate volume,PV)、PSA密度(PSAD)、经直肠指检(DRE)、经直肠前列腺超声(TRUS)和MRI等指标与前列腺穿刺活检阳性的相关性,建立联合常规临床检查的Logistic回归预测模型,绘制各项指标及预测模型的受试者工作特征(receiver-operating characteristic,ROC)曲线,计算与比较MRI与其他检查的曲线下面积。结果:本组242例患者中,102(41.2%)例患者MRI判定为阳性,其中64.7%(66/102)最终经组织病理学检查诊断为前列腺癌。多因素Logistic回归分析结果显示MRI(OR:14.563;95%CI:6.363~33.329)是前列腺穿刺结果的独立预测因素(P0.05)。ROC曲线下面积MRIPSAD年龄f/tPSADREPSATRUS,依次为0.813、0.726、0.723、0.657、0.642、0.598、0.569、0.568。MRI的ROC曲线下面积显著高于其他临床指标(P0.05)。联合MRI、PSAD、f/tPSA、DRE和TRUS的Logistic回归预测模型1,其ROC曲线下面积为0.892,与不包括MRI检查的预测模型2的ROC曲线下面积0.757相比,差异具有统计学意义(P0.05)。结论:联合MR-T2WI、DWI和DCE-MRI检查有利于对PSA水平在4~10μg/L前列腺癌的早期诊断,可以明显提高预测穿刺阳性的准确性。     

103例前列腺癌的诊断分析

目的 :提高前列腺癌的诊断水平。方法 :回顾分析 10 3例前列腺癌的临床资料 ,对前列腺癌的诊断方法进行探讨。结果 :单项PSA ,直肠指检 (DRE)及经直肠前列腺超声 (TRUS)检查诊断阳性率为 65 .9%～ 90 .3 % ,而前列腺穿刺诊断阳性率 95 .1%。结论 :前列腺穿刺活检对诊断前列腺癌具有重要意义。PSA、DRE、TRUS与前列腺穿刺结合可提高诊断的阳性率与准确率。     

游离PSA/总PSA<0.16在总PSA≤4ng/ml的前列腺癌患者中的前列腺穿刺指导价值

目的探讨游离PSA/总PSA(f/t)0.16对于总PSA≤4ng/ml的前列腺癌(PCa)患者是否具有指导前列腺穿刺的意义。方法回顾本院于2008年至2014年收治的总PSA≤4ng/ml的PCa患者的病历资料,分为4组,A组:f/t0.16;B组:f/t0.16且MRI或DRE阳性;C组:f/t≥0.16;D组:f/t≥0.16且MRI或DRE阳性。统计各组穿刺者人数及穿刺阳性率。结果共计73人进入本研究,A组32人,穿刺阳性率23.5%;B组9人,穿刺阳性率33.3%;C组41人,穿刺阳性率11.5%;D组12人,穿刺阳性率16.7%。A组与B组,A组与C组,B组与D组之间穿刺阳性率差别有统计学意义(P0.05)。C组与D组穿刺阳性率差别无统计学意义(P0.05)。结论对于总PSA≤4ng/ml的PCa患者,f/t0.16可以作为前列腺穿刺的指导指标,联合MRI或DRE检查可以提高前列腺穿刺阳性率。     

以前列腺特异抗原水平分组筛查与前列腺穿刺阳性率的关系

目的探讨不同血清前列腺特异抗原(PSA)水平前列腺癌检出情况以及直肠指诊(DRE)、经直肠超声检查(TRUS)、PSA密度(PSAD)等指标对筛查前列腺穿刺活检病例的意义。方法回顾性分析在1996年4月至2002年12月间行TRUS引导前列腺6点系统穿刺活检的634例患者的诊断资料,对各PSA组(≤4.0,4.1~,10.1~和>20.0μg/L组)中前列腺癌的检出率,以及PSA、DRE、TRUS、PSAD等对前列腺癌的预测作用进行t检验、χ2检验和多因素Logistic回归分析。结果PSA≤4.0,4.1~,10.1~和>20.0μg/L各组的前列腺癌检出率分别为11.6%(17/146),26.8%(38/142),39.8%(68/171)和68.6%(120/175)。PSA的敏感性最高(93.0%),特异性低(33.0%);DRE、TRUS等诊断效率较低。随血清PSA水平升高,前列腺癌检出率以及DRE、TRUS的阳性预测值逐渐升高;在PSA4.1~20.0μg/L者中,PSAD对前列腺癌有较大的预测价值(OR=687.09±646.96,P=0.000)。以PSAD≥0.13μg.L-1.cm-3为截点筛查前列腺穿刺病例,可在不明显降低敏感性的基础上,减少阴性穿刺。结论各PSA组国人与欧美等国前列腺癌检出率有较大差别;DRE、TRUS的筛查作用与血清PSA水平有关;按PSA水平分组筛查穿刺病例,可提高前列腺穿刺的阳性率。     

PAP、PSA与前列腺癌的诊断

本院从1992年7月至1996年9月收治经病理检查证实的前列腺癌52例,均行直肠指检(DRE)、B超、血清前列腺酸性磷酸酶(PAP)和前列腺特异抗原(PSA)检查,其诊断前列腺癌阳性率分别为78.8％、50.0％、61.5％、84..％。PSA阳性率明显高于其它检查(P<0.005)。若结合DRE、TRUS则诊断前列腺癌之敏感性达到96.2％。经直肠前列腺穿刺活检31例,穿刺阳性率为87.1％。PAP、PSA升高患者的比例与前列腺癌的分期、肿瘤细胞分化程仅具相关性。因此,PAP、PSA对前列腺癌的诊断、临床分期、判断预后有较大价值。     

152例前列腺腺癌的诊断分析

目的:探讨总PSA、游离PSA与前列腺穿刺、医学影像学诊断前列腺腺癌的价值。方法:采用统计学方法,回顾性分析152例前列腺腺癌患者诊断方面的临床资料。结果:152例患者游离PSA/总PSA(F/T)为0.17±0.11。若以0.20为界值,其阳性率可达77.6%;若以0.25为界值,其阳性率可达91.0%。对前列腺硬结患者行手法引导8针系统穿刺,其阳性率为77.6%;行B超引导下单纯结节穿刺,其阳性率为81.0%。74例前列腺腺癌患者中,69例经直肠前列腺超声(TRUS)检查阳性,71例MRI检查阳性。结论:F/T对“灰区”前列腺腺癌的鉴别诊断有积极意义;对前列腺硬结患者行单纯结节穿刺与系统穿刺,两者差别无统计学意义;TRUS和MRI检查对前列腺腺癌诊断价值的差别无统计学意义。     

建立一种简易评分系统预测前列腺穿刺活检前列腺癌阳性率

目的:分析经直肠前列腺穿刺活检前列腺癌阳性率的预测因素。方法:总结2006年1月至2014年4月进行经直肠超声引导下前列腺穿刺活检患者的资料,包括年龄(age)、体质指数(BMI)、症状(syptoms)、直肠指检(DRE)、血清总PSA(t PSA)、游离PSA(f PSA)、游离PSA与总PSA比值(f/t PSA)、前列腺体积(PV)、PSA密度(PSAD)。通过单因素方差分析和多因素回归模型,筛选与活检阳性率相关的危险因素。在此基础上构建一个评分系统作为在活检前预测前列腺癌阳性率的工具,并通过受试者工作特征(ROC)曲线计算假阳性率,以检测评分系统的敏感性。结果:在385例经直肠超声引导下穿刺活检患者中,共139例患者被诊断为前列腺癌,阳性率36.1%。单因素分析显示,在活检阳性组和阴性组之间,年龄(P<0.01)、DRE(P<0.01)、t PSA(P<0.01)、f PSA(P<0.01)、f/t PSA(P<0.01)、PV(P<0.01)和PSAD(P<0.01)在前列腺癌患者中比例均高于活检阴性人群。将单因素回归有意义的因素纳入多因素逐步Logistic分析,结果显示,年龄、t PSA、f/t PSA、PV和PSAD是经直肠反复前列腺活检阳性的独立影响因素,其比值比(ORs)及其相应的95%可信区间(95%CIs)分别为1.07(1.05~1.16)、1.05(1.02~1.15)、0.97(0.86~0.99)、0.98(0.87~0.96)和1.79(1.48~2.06)。根据其OR值,设定年龄>71岁(中位数)、t PSA>14.1μg/L(中位数)、f/t PSA<14.07(中位数)、PV<42.8 ml(中位数)、PSAD>0.31μg/L/ml(中位数)分别各计1分,总分为5分。将385例患者的资料通过评分系统计算前列腺癌的检出率,发现评分为0、1、2、3、4、5分的患者前列腺癌的检出率分别为7.69%、8.98%、15.19%、39.39%、54.55%和72.15%。ROC曲线提示曲线下面积为0.82(95%CI:0.80~0.84,P<0.01)。另外,评分3~5分的患者比0~2分的患者前列腺癌的检出率高50%以上(64%vs 11%,P<0.01)。结论:该评分系统可以帮助泌尿科医师确定需要行前列腺活检的患者。     

前列腺癌50例诊断分析

目的:分析我院前列腺癌诊断现状,以提高前列腺癌的早期诊断水平。方法:回顾性分析我院1998年4月~2003年4月收治的50例前列腺癌患者临床资料。50例患者分别通过直肠指检(DRE)、前列腺特异抗原(PSA)、经直肠B超(TRUS)、前列腺穿刺活检、CT、MRI、同位素骨扫描(ECT)等检查明确诊断。结果:DRE提示前列腺增大、质地坚硬或触及结节36例(72%);PSA<4×10-3ng/L 3例(6%),PSA(4~10)×10-3ng/L 7例(14%),PSA>10×10-3ng/L 40例(80%);前列腺穿刺活检阳性74.4%(32/43);TRUS诊断符合率84%(42/50);CT、MRI诊断符合率40%(20/50);ECT诊断符合率60%(30/50)。病理分期为A期和B期10例(20%),C期和D期40例(80%)。结论:前列腺癌的早期诊断仍是一个急待解决的问题,开展有关前列腺癌的预防教育工作,提高患者防范意识及医务人员的诊断意识,定期专科检查和加强特定人群的随访意识,可提高前列腺癌的早期诊断率。     

建立前列腺特异性抗原灰区患者重复穿刺阳性的数学模型

目的:建立预测前列腺特异性抗原(PSA)灰区患者重复穿刺阳性的数学模型。方法:选择2004~2016年158例血清PSA位于4~10ng/ml且首次穿刺病理结果为阴性的患者行重复穿刺,记录并分析患者的年龄、前列腺体积(PV)、PSA、游离PSA(fPSA)/总PSA(tPSA)、前列腺特异性抗原速率(PSAV)、前列腺特异抗原密度(PSAD)、前列腺移行带特异性抗原密度(PSAD-TZ)、超声检查(TRUS)、直肠指检(DRE)、高级别上皮内瘤变(HGPIN)、不典型小腺泡增生(ASAP)等重复活检结果的潜在预测指标。将有统计学意义的变量行二分类Logistic回归分析和建立数学模型,该模型的预测价值通过ROC曲线下面积(AUC)来评估。结果:158例前列腺重复穿刺活检患者中,前列腺癌的检出率为25.9%(41/158),单变量分析结果中统计学上有意义的指标包括Age、PV、f/tPSA、PSAD、PSAD-TZ、DRE、TRUS、Previous HGPIN、Previous ASAP(P<0.05),对以上所有变量进行二分类Logistic回归分析并建立数学模型,预测指标ASAP、HGPIN、f/tPSA、TRUS、DRE被纳入该模型。该模型AUC为89.8%,预测价值较高。结论:该数学模型可以很好的预测PSA患者重复穿刺阳性的概率,能够帮助临床医师判断哪些PSA灰区患者更适合行超声引导下前列腺重复穿刺活检术。     

基于临床及TRUS特点的前列腺结节恶性风险预测模型研究

目的:通过分析经直肠前列腺超声影像学特点及部分临床特征建立前列腺结节恶性风险预测模型,提高穿刺阳性率,减少不必要的前列腺穿刺。方法:回顾2010年1月~2014年1月在我院行前列腺穿刺活检且经直肠超声(TRUS)发现前列腺结节的患者151例。收集总前列腺特异性抗原(tPSA)、游离前列腺特异性抗原(fPSA)、f/t比值(fPSA/tPSA)、前列腺体积(PV)、PSA密度(PSAD)与经直肠前列腺B超发现的前列腺结节的大小、结节回声、结节位置、边缘是否清晰等资料,采用Logistic单因素分析寻找前列腺癌独立预测因子,Logistic多因素分析制定前列腺结节恶性风险预测模型。结果:142例患者入选,共170个结节纳入最终分析,其中恶性结节58例。单因素分析中结节位置、回声、边界是否清晰、lgPV、lgtPSA、f/t比值在恶性结节及良性结节组的分布差异有统计学意义,多因素分析中边界、lgtPSA、lgPV进入最终的风险预测模型。logit(前列腺癌)=4.081-1.090×边界-2.941×lgPV+1.836×lgtPSA。结论:本研究中受试者工作特征曲线下面积0.800,与国内外同类研究总体准确性相近,具有一定的准确性。     

Predictors of prostate cancer on repeat transrectal ultrasound-guided systematic prostate biopsy

BACKGROUND: We analyzed the outcome of repeated transrectal ultrasound (TRUS)-guided systematic prostate biopsy in Japanese men whose clinical findings were suspected of prostate cancer after previous negative biopsies. METHODS: Between January 1993 and March 2002, 1045 patients underwent TRUS-guided prostate biopsy. Among them, 104 patients underwent repeat biopsy due to indications of persistent elevated serum prostate-specific antigen (PSA), abnormal digital rectal examination (DRE) or TRUS, increased PSA velocity, and/or previous suspicious biopsy findings. Several clinicopathological factors were evaluated for their ability to predict the detection of prostate cancer on repeat biopsy. RESULTS: Prostate cancer was detected in 22 of 104 patients (21.2%) who underwent repeat biopsies. PSA concentration and PSA density at both the initial and repeat biopsies, and PSA velocity in men with positive repeat biopsy were significantly greater than those in men with negative repeat biopsy. The incidence of abnormal findings in DRE and TRUS at initial biopsy in men with positive repeat biopsy was also significantly higher than that in men with negative repeat biopsy. However, neither the presence of prostatic intraepithelial neoplasia nor number of biopsy cores at initial biopsy had a significant association with the results of the repeat biopsy. Furthermore, multivariate analysis revealed that PSA and PSA density at both the initial and repeat biopsies, PSA velocity, and DRE and TRUS findings at initial biopsy were independent predictors of malignant disease on repeat biopsy. CONCLUSION: Despite an initial negative biopsy, repeat TRUS-guided biopsy should be carried out to exclude prostate cancer in cases of suspicious clinical findings, such as elevated PSA or PSA-related parameters, or abnormal findings of DRE or TRUS.     

The value of prostatic specific antigen density in the early diagnosis of prostate cancer

In order to differentiate benign from malignant prostatic lesions, 42 patients were evaluated using the prostate specific antigen density (PSAD) test. All patients were evaluated with PSA determination, digital rectal examination (DRE), transrectal ultrasonography (TRUS) and ultrasound-guided prostatic biopsies. PSA was analyzed by the I-MX ABBOT assay. PSAD was determined by dividing the serum PSA by the volume of the prostate. Prostatic biopsies identified cancer in 3 of the 42 patients (6.38%). It is concluded that PSAD is valuable for the early diagnosis of localized prostatic carcinoma, especially when there are negative findings from DRE and/or TRUS.     

Repeat biopsy of the suspicious prostate cancer: especially the usefulness of MRI

Among patients with negative initial biopsies of the prostate, 51 patients underwent total 59 repeat biopsies at the Department of Urology of Ikeda Municipal Hospital between January 1998 and April 2004. Overall 26 patients (44.1%) were confirmed to have cancer, 22 patients by second repeat biopsy (22/51), four patients by third biopsy (4/7) and none by fourth biopsy (0/1). Clinical parameters (age, PSA, PSA density, PSA velocity) were analyzed for the possibility to predict the pathological outcome. Significant differences between the positive biopsy group and the negative biopsy group were obtained in age, PSA level and prostatic volume. Of the diagnostic evaluations including palpation and imaging studies (DRE, TRUS, MRI), the most powerful predictor for prostate cancer seemed to be the MRI findings, especially in the cases of short-interval repeat biopsy. Biopsies directed at the positive lesion on MRI in addition to systematic prostate biopsies should be useful.     

USEFULNESS OF DIGITAL RECTAL EXAMINATION, SERUM PROSTATE-SPECIFIC ANTIGEN, TRANSRECTAL ULTRAS ONOGRAPHY AND SYSTEMATIC PROSTATE BIOPSY FOR THE DETECTION OF ORGAN-CONFINED PROSTATE CANCER

The detection rate of organ-confined prostate cancer by digital rectal examination (DRE), serum prostate-specific antigen (PSA), and transrectal ultrasound (TRUS) of the prostate, as well as the value of a directed, guided transrectal core biopsy for the prostate (TRUS-guided biopsy) combined with systematic biopsy, were evaluated. The subjects were 171 patients with urinary symptoms suggestive of prostatic disease excluding those with clinical stage C and D prostate cancer. Twenty-five patients (14.6%) had prostate cancer, 127 (74.2%) had benign prostate hypertrophy, four (2.3%) had prostatic intraepithelial neoplasia, eleven (6.4%) had inflammation, and four (2.3%) had normal prostate tissue. The incidence of detection of hypoechoic findings by TRUS in the patients in whom nodules were detected by DRE or who had elevated serum PSA was higher than that in patients with negative diagnostic findings. In 22 of the 25 patients with prostate cancer, the cancer was detected by recognition of a hypoechoic area on TRUS. In 10 of these 22 patients, prostate cancer was also detected by systematic biopsy in isoechoic areas. Prostate cancer was detected by systematic biopsy in three patients without hypoechoic findings. The positive predictive value for patients with abnormal findings on all three tests was 64.3%, which is significantly higher than that for patients with any other combination of findings (p < 0.05). Our results indicate that the combination of DRE, serum PSA and TRUS is useful for the detection of organ-confined prostate cancer, and that TRUS and TRUS-guided prostate biopsy combined with systematic biopsy should be performed in patients with abnormal findings for both DRE and PSA. Our results also demonstrate that systematic biopsy is useful for the detention of prostate cancer from the isoechoic area visualized by TRUS.     

Early detection of prostate cancer in the ESRD population

BACKGROUND: There are currently no prostate cancer screening guidelines specific to the end-stage renal disease (ESRD) population. With this in mind, we evaluated the clinical usefulness of digital rectal examination (DRE), serum total prostate-specific antigen (PSA), prostate-specific antigen density (PSAD) and transrectal ultrasound (TRUS) in predicting prostate cancer in men with ESRD. METHODS: Fifty male ESRD patients age 40 years and older with no prior history of prostate cancer were enrolled in the study. All patients underwent PSA measurement and a DRE followed by a TRUS. PSAD was calculated as the total PSA divided by the prostate volume. Ultrasound-guided prostate biopsies were performed on any patient with 1 or more of the following abnormal findings: a nodule detected on DRE; an abnormal TRUS; PSA > 4.0 ng/ml, or a PSAD > 0.15 ng/ml/cm3. RESULTS: Abnormal findings were detected in 19 patients. Two (4%) had an abnormal DRE, 3 (6%) had PSA > 4.0 ng/ml, 3 (6%) had PSAD > 0.15 ng/ml/cm3 and 16 (32%) had abnormal findings on TRUS. Three patients had 2 abnormal findings and 1 had 3. Of the 15 prostate biopsies performed, 4 (27%) revealed prostate cancer and 3 (20%) high-grade prostatic intraepithelial neoplasm (HGPIN) comprising 8% and 6%, respectively, of the studied population. Of the 4 patients diagnosed with prostate cancer, none had abnormal DRE, 2 (50%) had PSA > 4.0 ng/ml (sensitivity = 66.7% and PPV = 50% (p = 0.236)), 3 (75%) had PSAD > 0.15 ng/ml/cm3 (sensitivity = 100% and PPV = 75% (p < 0.018)), and 3 (75%) had abnormal findings on TRUS (sensitivity = 30% and PPV = 75% (p = 1.000)). CONCLUSION: Routine screening with PSA and DRE does not seem sensitive enough to predict the presence of the disease. Although TRUS detected abnormalities in 16 patients (32%), sensitivity was very low (30%). In our patients, PSAD increased the sensitivity and positive predictive value (PPV) of detecting prostate cancers compared to PSA alone.     

Community‐based prostate cancer screening in Japan: Predicting factors for positive repeat biopsy

Objectives: To assess possible predictors in determining criteria for repeat biopsy in a prostate cancer screening population. Methods: A total of 50 207 men over 55 years‐of‐age have participated in a prostate cancer screening program in Otokuni, Kyoto, Japan for 12 years. Transperineal systematic biopsy was carried out in case of positive digital rectal examination (DRE) or positive transrectal ultrasonography (TRUS) or a prostate‐specific antigen (PSA) value greater than 10.0 ng/mL. For those with a PSA level from 4.1 to 10.0 ng/mL, and negative DRE and TRUS findings, biopsy was indicated only when PSA density (PSAD) was greater than 0.15. The same indication was applied for the repeat biopsy. Results: A repeat biopsy after an interval of more than 2 years was carried out in 140 patients and was positive in 50 (36%) patients. The PSA value at the diagnosis of cancer declined from the initial value in six (12%) patients. On multivariate logistic regression analysis, PSA velocity (PSAV) as well as PSAD and DRE findings at latest screening were independent predictors for positive repeat‐biopsy outcome. The odds ratio (95% confidence intervals) of PSAV >0.48, latest PSAD >0.33 and positive latest DRE were 4.17 (1.05–18.5), 4.15 (1.31–14.0), and 3.62 (1.06–13.2), respectively. A combination of three variables defined as positive if any of these were positive, reduced 31% of unnecessary biopsies while missing 8% of low volume, low grade cancers. Conclusions: A combination of latest PSAD, PSAV and positive DRE at latest screening might help to reduce unnecessary repeat biopsies in high‐risk patients with an initial negative biopsy.     

建立预测中国人前列腺重复穿刺活检阳性的数学模型

目的:建立可以预测国人经直肠超声引导下重复穿刺活检阳性的数学模型。方法:170例在首次穿刺活检诊断为前列腺良性病变的患者行重复穿刺。记录并分析患者的年龄、前列腺体积、血清PSA、游离PSA(f-PSA)/总PSA(t-PSA)、PSA上升速度、PSA密度(PSAD)、直肠指检(DRE)、首次穿刺病理结果等相关因素。将变量通过逐步回归建立回归方程,在此基础上建立重复穿刺活检阳性的危险评分数学模型。该模型的预测价值通过受试者工作曲线下面积来评估。结果:170例前列腺重复穿刺活检的患者中,前列腺癌的穿刺检出率为31.8%(54/170)。建立的数学模型影响因素包括:患者的年龄、前列腺体积、PSA、f-PSA/t-PSA、PSA上升速度、PSAD、DRE、首次穿刺结果是否为上皮内瘤变。该模型预测价值较高,曲线下面积为82.4%,大于患者PSAD、前列腺体积、PSA上升速度、f-PSA/t-PSA、DRE等单因素的66.9%、72.6%、69.6%、69.3%、58.5%。结论:该数学模型是临床多因素综合分析基础上建立的,可以很好地预测前列腺重复穿刺活检阳性的概率。     

Examination for indication of systematic biopsy for diagnosis of prostate cancer]

BACKGROUND: Systematic biopsy has been commonly used for detection of prostate cancer. Nevertheless, as this examination occasionally gives patients severe complications it is necessary to give careful consideration for application of this examination. Thus, we analyzed retrospectively 145 cases who underwent transrectal ultrasonography (TRUS) guided systematic biopsy to evaluate the application of systematic biopsy, correlating with the findings of digital rectal examination (DRE), prostate specific antigen (PSA), the findings of transrectal ultrasonography (TRUS) and the results of biopsies. METHODS: Between May, 1995 and May, 1997, 143 patients who were suspected to have prostate cancer with either of PSA and DRE, and 2 patients who received visual laser ablation of prostate (VLAP), underwent TRUS guided systematic biopsy of prostate. We evaluated diagnostic efficacy of PSA, DRE, TRUS, prostate-volume-specific PSA, and PSA density (PSAD). RESULTS: Sensitivity, specificity and positive predictive value (P.P.V.) are 78.4%, 62.8% and 53.5% for DRE, 100.0%, 4.4% and 41.8% for PSA, 88.2%, 60.0% and 52.9% for TRUS, 87.8%, 72.1% and 64.2% for prostate-volume-specific PSA, 100.0%, 30.6% and 45.4% for PSAD, respectively. Ten of 69 patients (14.5%) whose PSA levels were 4.0 to 10.0 ng/ml were diagnosed as cancer, and positive for both or either of DRE and TRUS. Twenty-seven who were negative for both of DRE and TRUS were not diagnosed as prostate cancer. Using the combination of prostate-volume-specific PSA, DRE and TRUS, we could eliminate 29 non-cancer men (21.5%) whose PSA level was greater than 4.0 ng/ml from systematic biopsy. CONCLUSION: On the diagnosis of prostate cancer, the combination of prostate-volume-specific PSA, DRE and TRUS is very useful to exclude unnecessary systematic biopsy, if an urologist could be used to and trained for DRE and TRUS.     

ROLE OF PROSTATE-SPECIFIC ANTIGEN AND DIGITAL RECTAL EXAMINATION IN THE DETECTION OF PROSTATE CANCER

Prostate-specific antigen (PSA) is a kallikrein-like serine protease that is secreted exclusively by the epithelial cells of all types of prostatic tissue, benign and malignant. Its serum concentration is raised in men with prostatic disease including cancer. We have evaluated its usefulness in the diagnosis of prostate cancer by measuring serum PSA concentrations in 260 men aged 50 years or over. All had abnormalities at digital rectal examination (DRE) involving suspected cancer, signs and symptoms of benign prostatic hyperplasia and equivocal findings on DRE, and miscellaneous other conditions, including hematospermia, chronic prostatitis and microscopic hematuria. Transrectal prostatic needle biopsies were performed in the men with abnormal findings on DRE or elevated serum PSA (above 4ng/ml). Serum PSA ranged from 4.0 to 9.9ng/ml in 14 (5%) of the 260 men. Four of the men in this group (31%) who underwent prostatic biopsy had prostate cancer. Serum PSA levels greater than or equal to 10.0 ng/ml were found in 8 (3%) of the 260 men. 5 of these 8 (63%) who underwent prostatic biopsy had cancer. If DRE alone had been used to screen the men having biopsies, 4 of the 10 cancers (40%) would have been missed. If PSA alone had been used to screen these men, only 1 of the 10 cancers would have been missed. Serum PSA measurement was more reliable than DRE for detecting prostate cancer. Since these two methods do not always detect the same malignant tumor, the combined use of DRE and PSA testing affords a more complete evaluation of the prostate gland for malignant involvement.     

Evaluation of Prostate Specific Antigen Density and Transrectal Ultrasonography-Guided Biopsies in 100 Consecutive Patients with a Negative Digital Rectal Examination and Intermediate Serum Prostate Specific Antigen Levels

Background : This study was undertaken to assess the importance of prostate biopsies in patients with a negative digital rectal examination (DRE) and elevated prostate specific antigen (PSA) levels and to investigate the role of PSA density (PSAD) and hypoechoic lesions on transrectal ultrasound (TRUS) in increasing the diagnostic sensitivity and specificity for prostate cancer (PCa). Methods : One hundred patients with varied initial symptoms who had a negative DRE and a PSA level between 4 and 20ng/mL underwent TRUS-guided systematic and, if present, lesion-directed biopsies. Results : PCa was detected in 11 patients (11%). TRUS examinations revealed hypoechoic lesions in 31 patients. Lesion-directed biopsies revealed PCa in 1 3% (4/31) of patients with abnormal TRUS whereas, 7% (5/69) of patients with negative TRUS findings had PCa. Additional systematic biopsies detected PCa in 2 patients where lesion-directed biopsies were negative. None (0/19) of the lesions smaller than 0.2 ml on TRUS had PCa whereas, 33% (4/1 2) of patients with lesions greater than 0.2 ml had PCa. When the subgroup of patients with negative TRUS and PSA levels between 4 and 10ng/mL were considered, 25% (1/4) of cases with PCa would have been missed if 0.15 was used as the cut-off point for PSAD, however, this would save 61% (30/49) of unnecessary biopsies. The positive predictive value of PSA (cut-off level lOng/mL), PSAD (cut-off level 0.15), and hypoechoic lesions on TRUS were found to be 11.5%, 33%, and 13%, respectively. When hypoechoic lesions greater than 0.2 mL were taken as the positive finding, the positive predictive value and specificity rates of TRUS increased to 33% and 91 %, respectively, without any change in the sensitivity. Conclusions : In patients with a negative DRE and intermediate PSA levels, the application of PSAD would have saved 49% of study patients with BPH from a biopsy, but would have missed 27% of PCa cases. By ignoring lesions smaller than 0.2 mL on TRUS, a very high specificity of 91% was achieved with a sensitivity of 36%. Thus, further investigations aimed at defining a better mode of diagnosis of PCa are warranted.