Evaluation of prostate specific antigen (PSA) adjusted to transition zone in prostatic cancer detection

ObjectiveTo investigate if PSA adjusted to transition zone (PSA-TZ) can be considered as a predictor parameter of cancer with better specificity or not than PSA, PSA density (PSAD) or PSA free/total ratio.Material and methodsData of 706 patients with sextant prostatic biopsies are analyzed in prospective way because of prostatic cancer suspicion. Range of PSA was between 4 to 20 ng/ml. Determination of PSA-TZ was calculated by dividing the PSA value by the volume of the transition zone of the prostate applying the ellipsoid formula and comparison of obtained results in detection of cancer was performed by ROC curves analysis for each one of PSA-related parameters.ResultsOf the total group of patients, in 199 cases (28.2%) prostatic cancer was detected. Analysis by ROC curves demonstrated than PSA-TZ and PSAD were better predictors of cancer than PSA free/total ratio and PSA (p<0.0001). The cutoff value of PSA-TZ of 0.18 ng/ml/cc was considered as the best, obtaining a 95% sensitivity and a 27% specificity. For this sensitivity, PSA, PSAD and PSA free/total ratio only obtained 5, 9 and 16% specificity respectively. Areas under curve (AUC) obtained for PSA, PSA free/total ratio, PSAD and PSA-TZ were 0.539, 0.612, 0.694 and 0.722 respectively.ConclusionsPSA-TZ in the studied population was a parameter with better diagnostic specificity than PSA, PSAD and PSA free/total ratio for the same 95% sensitivity. This would justify its utility in clinical paractice reducing the number of unnecesary biopsies.     

Prediction of extraprostatic cancer by prostate specific antigen density,endorectal MRI,and biopsy Gleason score in clinically localized prostate cancer

BACKGROUNDS: The present study was designed to identify the preoperative parameters, including PSA-based parameters, and endorectal MRI, predictive of pathological stage in males who underwent radical prostatectomy. METHODS: We studied 114 patients who underwent radical retropubic prostatectomy and pelvic lymphadenectomy for clinically localized prostate cancer. Clinical stage was assessed by DRE, pelvic CT scan, endorectal MRI, and bone scan. The correlation between the preoperative parameters, including PSA-based parameters, clinical stage, and histological findings of biopsy specimens, and the pathological stage was analyzed. Logistic regression analysis was performed to identify a significant set of independent predictors for local extent of disease. RESULTS: Seventy-six (66.6%) patients had organ confined cancer and 38 (33.4%) patients had extraprostatic cancer. Of the 38 patients with extraprostatic cancer, four had seminal vesicle involvement, while, none had pelvic lymph node involvement. Biopsy Gleason score, PSA, PSA-alpha1-antichymotrypsin (PSA-ACT), PSA-density (PSAD), PSA-transition zone density, PSA-ACT density, and PSA-ACT transition zone (TZ) density were significantly higher and percent free PSA was lower in the patients with organ confined cancer than those with extraprostatic cancer (P < 0.01). PSAD showed the largest area under the ROC curve (AUC) among those parameters (AUC = 0.732). Sixty-eight (74.7%) of 91 patients with T2 on endorectal MRI had organ confined cancer, while 15 (65.2%) of 23 patients with T3 had extraprostatic cancer (P < 0.01). Multivariate logistic regression analysis indicated that Gleason score (> or =7 vs. < or =6), endorectal MRI findings, and PSAD were significant predictors of extraprostatic cancer (P < 0.01). CONCLUSIONS: The present study demonstrated that preoperative PSAD was the most valuable predictor among PSA-based parameters for extraprostatic disease in patients with clinically localized prostate cancer. The combination of PSAD, endorectal MRI findings, and biopsy Gleason score can provide additional information for selecting appropriate candidates for radical prostatectomy.     

前列腺特异性抗原密度的测定在诊断前列腺癌中的价值

对１０例非转移性前列腺癌和２０例前列腺增生的前列腺特异性抗原密度（ＰＳＡＤ）进行研究。前列腺癌平均ＰＳＡＤ值为０．７１１，而前列腺增生为０．０７５；两者有极显著性差异（Ｐ＜０．００１）。９例ＰＳＡＤ＞０．２者，８例为前列腺癌。１６例ＰＳＡＤ＜０．１者，无１例前列腺癌。８例前列腺癌患者中有３例前列腺特异性抗原（ＰＳＡ）＜１０ｎｇ／ｍｌ，１例＜２．８ｎｇ／ｍｌ。１６例前列腺增生患者中７例ＰＳＡ＞２．８ｎｇ／ｍｌ，３例＞１０ｎｇ／ｍｌ。表明血清ＰＳＡ轻中度增高或正常时，ＰＳＡＤ可作为前列腺癌早期筛选诊断的有效指标之一。     

Biochemical (prostate specific antigen) recurrence probability following radical prostatectomy for clinically localized prostate cancer

PURPOSE: We retrospectively reviewed the clinical followup for a large series of men with clinically localized prostate cancer who underwent radical retropubic prostatectomy to identify clinical and/or pathological indicators of biochemical (prostate specific antigen [PSA]) recurrence. We then used those indicators to develop multivariate models for determination of recurrence probability following radical retropubic prostatectomy. MATERIALS AND METHODS: From 1982 to 1999, 2,091 consecutive men underwent radical retropubic prostatectomy and pelvic lymphadenectomy for clinically localized adenocarcinoma of the prostate (clinical stage T1c or T2 disease with Gleason score 5 or greater). Actuarial analysis was performed comparing freedom from biochemical recurrence after radical retropubic prostatectomy (PSA 0.2 ng./ml. or greater.) using the Kaplan-Meier method. Event time distributions for the time to recurrence were compared using the log rank statistic or the Cox proportional hazards regression model. The first model was developed using preoperative variables only and the second model using all available variables. Observed and predicted recurrence-free survival curves for different models were compared to select a model for calculation of predicted recurrence-free probabilities and confidence intervals. RESULTS: With a median followup of 5.9 years (range 1 to 17) 360 men (17%) had biochemical recurrence. Overall actuarial 5, 10 and 15-year biochemical recurrence-free survival rates were 84%, 72% and 61%, respectively. The relative risk of biochemical recurrence following surgery decreased with time, even after adjusted for other perioperative parameters. Variables identified for the preoperative model were biopsy Gleason score, clinical TNM stage and PSA. Variables identified for the postoperative model were prostatectomy Gleason score, PSA and pathological organ confinement status. Nomograms were generated and corrected for the decreasing relative risk of biochemical recurrence over time. CONCLUSIONS: Using 3 preoperative or postoperative parameters, these nomograms can easily be used to determine the 3, 5, 7 and 10-year biochemical recurrence-free survival probabilities among men who undergo radical retropubic prostatectomy for clinically localized prostate cancer in the modern era.     

前列腺癌体积的临床预测及其意义

目的　研究以术前前列腺活检资料来推断前列腺癌体积及病理的价值。方法　以 3 3例因前列腺癌而行根治术的患者作为研究对象 ,将术前PSA、PSAD及前列腺 8点活检的结果与前列腺癌体积及病理进行相关分析研究。结果　 (1)前列腺癌体积与术前PSA、PSAD及前列腺活检的结果呈显著正相关 ,而与年龄、术前前列腺体积以及摘除标本的体积无明显相关关系 ;(2 )前列腺活检中阳性点数联合PSA与前列腺癌体积的回归模型预测前列腺癌体积最好 ;(3 )前列腺活检中阳性点数≤ 3点组的癌体积及精囊浸润率低于阳性点数≥ 4点组 ,两者有显著性差异。结论　前列腺 8点活检中阳性点数是预测前列腺癌体积及病理的一个重要参考指标 ,尤其是联合检测PSA ,更增加其预测前列腺癌体积的准确性     

游离前列腺特异抗原百分比/前列腺特异抗原密度在前列腺癌诊断中的应用

目的探讨游离前列腺特异抗原百分比（FPSA／TPSA值）／前列腺特异抗原密度[（F／T）／PSAD值]在前列腺癌诊断中的意义。方法回顾分析204例行经直肠超声引导前列腺穿刺活检患者的诊断资料,其中前列腺癌90例、良性前列腺增生114例,分析总PSA（TPSA）、FPSA／TPSA值、PSAD、（F／T）／PSAD值等指标在判断前列腺癌的敏感性为90％时的截点及相应的特异性。结果不同血清PSA水平（〈4．0,4．0～,10．1～和〉20．0μg／L）的前列腺癌患者的（F／T）／PSAD值与良性前列腺增生患者比较,差异有统计学意义（P〈0．05）;前列腺癌患者的（F／T）／PSAD值低于良性前列腺增生患者;（F／T）／PSAD值比FPSA／TPSA值和PSAD更有助于提高诊断特异性,在敏感性为90％左右的前提下,FPSA／TPSA值的特异性为31．6％,PSAD的特异性为45．6％,（F／T）／PSAD值的特异性为64．0％;PSA水平不同,取的（F／T）／PSAD值截点也不同：PSA〈4．0μg/L时截点为2．5,PSA为4．0～20．0μg／L时截点为0．8;PSA〉20．0μg／L时截点为0．5。结论应用（F／T）／PSAD值能够在保持较高敏感性的前提下,显著提高前列腺癌诊断的特异性。     

An algorithm for prostate cancer detection in a patient population using prostate-specific antigen and prostate-specific antigen density

Summary Prostate-specific antigen (PSA) is the most accurate serum marker for cancer of the prostate (CaP). However, its sensitivity and specificity are suboptimal, especially at values ranging between 4.1 and 10.0 ng/ml (monoclonal), because benign prostatic hypertrophy and hyperplasia (BPH) and CaP frequently coexist in this range. This study was undertaken to determine the value of incorporating prostate volume measurements with serum PSA levels in a quotient (PSA/volume) entitled PSA density (PSAD). A total of 3140 patients were analyzed and stratified by serum PSA, digital rectal examination (DRE), transrectal prostate ultrasound (TRUS), TRUS volume determination and PSAD. All patients were referred for evaluation and therefore do not represent a screened population. Patients underwent prostate biopsies when abnormalities in TRUS or DRE were detected. Although both PSA and PSAD have statistical significance when the serum PSA value is 4.0 ng/ml, neither has clinical significance in differentiating BPH from CaP. At serum levels ranging between 4.1 and 10.0 ng/ml, PSA has no ability to differentiate BPH from CaP, whereas PSAD does so with statistical and clinical significance. When the PSA value is between 10.1 and 20.0 ng/ml, only PSAD is statistically significant. When PSA exceeds 20 ng/ml, PSAD is redundant. We conclude that all patients with an abnormality on DRE or TRUS should undergo prostate biopsy. If the PSA value is 4.0 ng/ml, TRUS and PSAD are not warranted and routine biopsy is not recommended. For intermediate PSA levels, 4.1–10.0 ng/ml, TRUS, TRUS prostate volume, and PSAD are important. The use of PSAD provides unique information regarding the need for biopsy and the likelihood of CaP. At PSA levels ranging between 10.1 and 20.0 ng/ml, PSAD will identify those patients who are less likely to have CaP, but all should undergo biopsy. If the PSA value is >20 ng/ml, all patients should undergo a biopsy.     

Prostate specific antigen density for discriminating prostate cancer from benign prostatic hyperplasia in the gray zone of prostate-specific antigen.

Serum prostate specific antigen (PSA) is currently the best blood marker for prostate cancer. However, low specificity for detection of prostate cancer, especially in the gray zone of PSA, is a problem. We evaluated the clinical significance of PSA density (PSAD) in gray zone PSA cases with conversion of serum PSA to a Stanford reference value. In a series of histologically confirmed 63 benign prostatic hyperplasia (BPH) patients and 234 prostate cancer patients, 36 BPH patients and 25 prostate cancer patients had gray zone PSA levels. Serum PSA was measured with the Markit-F or Markit-M PA assay. All data were converted to Stanford reference values. We used transabdominal ultrasound to determine prostate volume. PSAD was determined as the serum PSA/prostate volume ratio. The mean PSA values for BPH and prostate cancer were 6.42 +/- 1.80 and 7.80 +/- 2.15 ng/ml (p = 0.0116), respectively, and prostate volume was 33.4 +/- 14.1 ml and 17.1 +/- 8.2 ml, respectively (p < 0.0001). The mean PSAD for prostate cancer was 0.572 +/- 0.363 while that for BPH was 0.218 +/- 0.085 (p = 0.0001). Cut-off values with sensitivity > 90% were 0.218 for PSAD and 30 ml for prostate volume. At these cut-off values, specificity reached 56% for each marker. In discriminating prostate cancer from BPH in the gray zone of PSA, PSAD demonstrated better performance than PSA.     

血清PSA密度变化对前列腺癌高危人群的诊断价值

目的:探讨前列腺特异抗原(PSA)、前列腺特异抗原密度(PSAD)变化对前列腺癌高危人群的诊断价值。方法:对初次活检阴性的432例患者进行随访,其中79例重复穿刺活检,确诊前列腺癌27例(34.2%),消化道来源肿瘤1例,BPH25例,前列腺上皮内肿瘤(PIN)13例,慢性前列腺炎13例。对重复活检患者的PSA、PSAD等临床资料进行统计分析。结果:配对t检验显示,良性病变首末次穿刺前PSA、PSAD差异均无统计学意义,而前列腺癌末次穿刺前PSA、PSAD较首次穿刺前升高,差异有统计学意义。以PSA>4ng/ml筛选前列腺癌,其敏感性、特异性、阳性预测值分别为92.5%、17.6%、37.6%,PSA末-PSA首>0筛选前列腺癌的敏感性、特异性、阳性预测值分别为85.2%、41.2%、40.4%;而以PSAD末-PSAD首>0筛选前列腺癌的敏感性、特异性、阳性预测值分别为81.5%、54.9%、48.9%。结论:在前列腺癌高危人群中应该重复穿刺,以减少漏诊;以PSAD动态升高来指导穿刺,可以明显提高阳性率。     

Retrospective evaluation of PSA density for selection of biopsy candidates with prostate specific antigen in the gray zone

PURPOSE: We examined the usefulness of prostate specific antigen density (PSAD) for selection of biopsy candidate with prostate specific antigen levels between 4.1 and 10.0 ng./ml. in prostate cancer screening retrospectively. MATERIALS AND METHODS: The screening was conducted on male candidates in Natori city, aged 55 years or older, for 6 years from 1994 through 1999. We could analyze serum PSA levels and PSA density in 118 men with PSA levels between 4.1 and 10.0 ng./ml. All of 118 men underwent ultrasound guided systematic prostate biopsy regardless of findings of digital rectal examination and transrectal ultrasound. Prostate volume was estimated by transrectal ultrasound measurements using the prolate ellipse formula (pi/6 x length x width x height). PSAD was calculated by dividing serum PSA level by prostate volume. Serum PSA levels were determined by Tandem-R assay. RESULTS: In 118 men, twenty-five men had prostate cancer. There was no significant difference in mean PSA between those with prostate cancer and those without prostate cancer, but the difference was significant in the mean PSA density (mean 0.26 and 0.16, respectively, p < 0.0001). Receiver operating characteristic curves for PSA and PSAD demonstrated superior benefit for PSAD in 118 men. A sensitivity, a specificity, a positive predictive value and a negative predictive value of PSAD cut-off of 0.15 were 88%, 52.7%, 33.3% and 94.2%. PSAD cut-off of 0.18 showed the highest sum of sensitivity and specificity, which gave a sensitivity of 80%, a specificity of 72%, a positive predictive value of 43.5% and a negative predictive value of 93.1%. PSAD cut-off of 0.15 would seem to be preferable to cut-off of 0.18 because of less cancer missing. CONCLUSIONS: Although further studies are needed to determine optimal cut-off value to be used in clinical practice, PASD seems to be useful for the selection of biopsy candidates with PSA levels of 4.1 to 10.0 ng./ml. in the prostate cancer screening.     

Effectiveness of percent free prostate specific antigen as a predictor of prostate cancer detection on repeat biopsy

BACKGROUND: The aim of this study was to identify predictors that can increase the accuracy of detecting prostate cancer on subsequent biopsies. METHODS: Between 1998 and 2003, a total of 235 men with prostate specific antigen (PSA) levels between 4.0 and 20 ng/mL underwent one or more systematic needle biopsies of the prostate. Of these men, 73 (31.1%) underwent one repeat biopsy and 26 (11.1%) underwent two or more repeat biopsies. We evaluated the results of prostate biopsies in relation to the morbidity of prostate cancer detected on repeat biopsies. RESULTS: Of the 73 men who underwent repeat biopsy, 16 (21.9%) had prostate cancer. Twenty-six men with one negative re-biopsy underwent two or more repeat biopsies, and five of these patients were found to have early stage prostate cancer. On repeat biopsy, there was a significant difference in percent free PSA between the cancer-detected group and the no-cancer-detected group (P < 0.01). A receiver operating characteristics (ROC) curve gave an optimal cut-off value for percent free PSA of 11%, demonstrating a significant difference in the cancer detection rate on repeat biopsy (P = 0.0009). Analysis of the data for re-biopsies showed that cancer-detected cases showed a raised PSA value and a simultaneously reduced percent free PSA (these differences were statistically significant). CONCLUSIONS: A low percent free PSA level increased the probability of a positive result in repeat biopsy. An increase in the accuracy of detecting cancer, especially on repeat biopsy, will promote the detection of more early stage prostate cancer.     

Prostate-specific antigen complexed to alpha(1)-antichymotrypsin in the early detection of prostate cancer

OBJECTIVES: To study the usefulness of the complexed-to-total (C:T) prostate-specific antigen (PSA) ratio in the early detection of prostate cancer in patients with a total PSA value <4.0 ng/ml. PATIENTS AND METHODS: Total PSA and PSA complexed to alpha(1)-antichymotrypsin were measured in plasma from 193 men with benign prostatic hyperplasia (BPH) and 34 with prostate cancer. The diagnosis was confirmed in 28 BPH and 16 prostate cancer patients by biopsy and in 165 BPH and 18 prostate cancer patients by histological study following transurethral prostatectomy or open prostatectomy. RESULTS: The area under the receiver operating characteristic (ROC) curve was significantly greater for the C:T PSA ratio (0.908) than for total PSA (0.692) (p<0.001). Using a cut-off point of 0.83 for the C:T PSA ratio and regardless of the digital rectal examination (DRE) finding, 20 of the 34 prostate cancer patients would have been given a correct diagnosis (59% sensitivity) and in only 8 of the 193 BPH patients would a biopsy have been necessary (96% specificity). With a cut-off of 0.79, the sensitivity increased to 85% with a specificity of 92%. When the analysis was restricted to the 44 patients with abnormal DRE, the area under the ROC curve for the C:T PSA ratio was 0.919, and a cut-off point of 0. 78 gave a sensitivity of 87% and a specificity of 93%. Using a cut-off of 0.63, all prostate cancers were detected (100% sensitivity) and 54% of the negative biopsies would have been eliminated. For the 183 patients diagnosed following surgery, a cut-off of 0.82 gave a sensitivity of 72% and a specificity of 94%. CONCLUSION: Our results show that the C:T PSA ratio significantly improves the clinical utility of the PSA assay for detecting prostate cancer in patients with total PSA < 4 ng/ml, increasing the sensitivity without significantly increasing the number of biopsies.     

Follow-up of men with elevated prostate-specific antigen and one set of benign biopsies at prostate cancer screening

OBJECTIVE: To study the follow-up of men with elevated prostate-specific antigen (PSA) (>3 ng/ml) after one benign set of sextant biopsies. From the G?teborg branch of the European Randomised Study of Screening for Prostate Cancer (ERSPC). METHOD: 456 men with one set of benign sextant biopsies were followed every second year for 4 years with PSA determinations. In cases of elevated PSA, transrectal ultrasound (TRUS) guided sextant biopsies were suggested. Digital rectal examination (DRE), prostate volume, PSA, PSA density (PSAD) and the ratio between free and total PSA (PSA F/T) were recorded. RESULTS: Complete data were available for 322 men. 3 groups were identified. In 84/322 (26%) men cancer was found ("cancer" group). 182/322 (56%) had benign biopsies ("benign" group) and 56/322 (17%) had normalised PSA ("normalised PSA" group). Median prostate volumes were 36, 46, and 33 cc respectively in the three groups. DRE and/or TRUS were abnormal in only 30% of the men in all groups. Cancer was not found in any prostate >70 cc volume. In prostates of <20 cc either cancer was found or PSA was normalised. The "normalised PSA" group had initial PSA, PSAD and PSA F/T similar to cancer, normalising during follow-up. CONCLUSIONS: Patients with one negative sextant biopsy still have a high likelihood of cancer, especially men with persistently elevated PSA and small prostates (<20 cc) while the majority of men with large prostates (>70 cc) have PSA elevation due to benign prostate hyperplasia (BPH) and not to cancer.     

Prediction of focal extracapsular extension at radical prostatectomy: Relative merit of transrectal ultrasound, endorectal magnetic resonance imaging, prostate specific antigen, prostate specific antigen density, and systematic biopsy

We conducted a study to compare the relative merits of prostate specific antigen (PSA), PSA density (PSAD), transrectal ultrasound (TRUS), endorectal magnetic resonance imaging (MRI), and systematic biopsy in the prediction of focal extracapsular extension (ECE) at radical prostatectomy. A retrospective review of patients who underwent TRUS, endorectal MRI, and radical prostatectomy at our institution was performed. Patients with a diagnosis of prostate cancer who were thought to be surgical candidates by digital rectal examination and TRUS underwent endorectal MRI prior to radical prostatectomy. Imaging, PSA, PSAD, and systematic biopsy results (tumor grade and fraction of positive systematic biopsies) were correlated with step-sectioned, radical prostatectomy pathologic data. Data was analyzed for the entire prostate and on each individual side. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and likelihood ratios were calculated for each modality, and receiver operating characteristic (ROC) curves were generated. Stepwise logistic regression analysis was used to weigh the relative contributions of preoperative parameters in predicting ECE.

Data was collected from 54 patients who had sextant systematic biopsy, imaging, and radical prostatectomy. A total of 24 sides demonstrated ECE (19 patients, 5 with bilateral ECE). When assessed for the dominant prostate side and on a side-for-side basis, MRI had the highest sensitivity and NPV for detecting focal ECE. MRI also had the highest PPV, and TRUS had the highest specificity for side-for-side analysis. For the dominant prostate side, PSA had the highest specificity and PPV for detecting focal ECE. Of note, significant overlap was demonstrated in the 95% confidence intervals of all modalities with each other for all analyses. ROC analyses found MRI and Gleason sum to be superior for the dominant prostate side assessment and MRI and the fraction of positive systematic biopsies to be superior for a side-for-side analysis. Optimal likelihood ratios for positive test results were seen for PSA (dominant prostate side) and MRI (side-for-side), and for negative test results for MRI. Logistic regression demonstrated MRI and Gleason sum to be powerful predictors of ECE. Thus, we would conclude that endorectal MRI and tumor grade provide unique information in the prediction of focal ECE in select patients.     

Prostate-specific antigen density — a reliable parameter for the detection of prostate cancer?

Summary We compared the prostate-specific antigen density (PSAD) in clinically and surgically staged patients with specimen-confined prostate cancer (n=57) and in patients with benign hyperplasia (n=69), who underwent transvesical adenomectomy. The PSAD was calculated from the preoperative PSA level and the specimen volume. The prostate volume was determined by dividing the prostate weight by the specific gravity of the tissue. The mean tissue values used for PSAD calculation were 51.9 g in men with prostate cancer (PCA) and 62.9 g in men with benign prostatic hyperplasia (BPH). The PSAD values showed significant differences (BPH 0.19 versus PCA 0.37,P=0.029). Receiver operator characteristic (ROC) curves demonstrated the best cutoff value to be 0.15, with the sensitivity being 58%; the specificity, 51% and the positive predictive value of PCA, 49%. At a serum PSA level below 10 ng/ml, the best cutoff value was 0.1 and the positive predictive value was 51%. The PSAD results we calculated from an accurate prostate volume (surgical estimate) show that PSAD is not a significant predictor of prostate cancer.     

Study of free to total prostate specific antigen ratio in the detection of patients with prostate cancer

BACKGROUND: We investigated the clinical usefulness of free to total serum prostate specific antigen (PSA) ratio (F/T ratio) in order to improve the specificity of total PSA measurement for detecting prostate cancer. METHOD: In this study 129 patients with total PSA level 4-20 ng/ml underwent transrectal ultrasound guided sextant biopsy. Serum samples were assessed for total PSA, free PSA and the F/T ratio calculated. All patients were pathologically diagnosed as benign prostatic hyperplasia or prostate cancer. RESULTS: Of 129 patients 21 had prostate carcinoma (PCa) and 108 had benign prostatic hyperplasia (BPH) from the results of prostate biopsies. The mean of total PSA were not significantly different between men with PCa and with BPH. The mean of free PSA for PCa was significantly lower than that for BPH (p = 0.043). Furthermore, the mean of F/T ratio was significantly different between PCa and BPH group (p = 0.0014). The F/T ratio had a higher specificity than total PSA at all levels of sensitivity in detecting prostate cancers. Sensitivity, specificity and accuracy for cancer detection at a cut off 0.12 was 90.4%, 51.8% and 58.1%, respectively. Also, free PSA was as useful as F/T ratio for cancer detection when analyzed in receiver operating characteristic curves analysis. When determined the cut off number of free PSA at 0.78 ng/ml, the sensitivity, specificity and accuracy for cancer detection were 61.9%, 66.7% and 65.9%, respectively. CONCLUSION: This study indicated that the F/T ratio and free PSA could improve the specificity without impairing the sensitivity for detecting PCa in patients with 4-20 ng/ml of total PSA.     

Volume-adjusted prostate-specific antigen (PSA) variables in detecting impalpable prostate cancer in men with PSA levels of 2-4 ng/mL: transabdominal measurement makes a significant contribution

OBJECTIVE: To examine whether prostate-specific antigen (PSA) levels adjusted according to prostate volume improve prostate cancer detection using transrected biopsies in men with PSA levels of 2-4 ng/mL, and benign findings on a digital rectal examination (DRE). PATIENTS AND METHODS: Men aged < or = 79 years and with serum PSA levels of 2-4 ng/mL and normal DRE findings were prospectively enrolled. Eligible patients were recommended for transrectal prostate biopsies after measuring prostate volumes with transrectal (TRUS) and transabdominal (TAUS) ultrasonography, and transition zone volumes with TRUS. In addition to PSA levels and the free-to-total PSA ratio, volume-adjusted PSA levels, PSA densities determined by TRUS (PSAD(TRUS)), and TAUS (PSAD(TAUS)), and PSA transition zone densities (PSATzD) were compared using receiver operating characteristic analysis. RESULTS: Prostate cancer was diagnosed in 31 (22%) of the 139 men who had prostate biopsies. The area under the curve (AUC) of PSAD(TRUS) (0.796) and PSATzD (0.792) was similar and significantly greater than that of PSA (AUC 0.588) and the free-to-total PSA ratio (AUC 0.658). PSAD(TAUS) was a significantly better indicator of prostate cancer than PSA levels alone (P = 0.043). CONCLUSION: As predictors of prostate cancer, there were no significant differences between PSAD(TRUS) and PSATzD. Although PSAD(TAUS) was worse than PSA variables adjusted by total and transition zone prostate volumes determined by TRUS, it was a better predictor than the PSA value alone in men with a low PSA level. These results indicate that TAUS is worthwhile where the routine use of TRUS before biopsy is difficult.     

The ability of systematic transrectal ultrasound guided biopsy to detect prostate cancer in men with the clinical diagnosis of benign prostatic hyperplasia.

Multiple directed and systematic ultrasound guided biopsies of the prostate were performed in 73 men with the clinical diagnosis of benign prostatic hyperplasia (BPH). Seven men (10%) had prostate cancer. Of the 67 patients with benign biopsies 40 underwent subsequent transurethral prostatectomy and 2 (5%) had prostate cancer. Multiple directed and systematic biopsies of the prostate detected 78% of the nonpalpable prostate cancers diagnosed in the study population. Radical prostatectomy was performed in all 9 men with prostate cancer: there were 3 small organ-confined tumors, 5 large organ-confined tumors and 1 stage C tumor with 1 focus of microscopic capsular penetration. Our results suggest that multiple directed and systematic ultrasound guided biopsies are capable of detecting low volume nonpalpable prostate cancer in men with BPH. However, the exact indication for pre-treatment ultrasound guided biopsy of the prostate in men with symptomatic BPH remains unclear. It may be that use of this modality is most appropriate for patients undergoing pharmacological therapy or balloon dilation of BPH rather than for those undergoing transurethral prostatectomy.     

PSA相关标志物在前列腺癌诊断中的价值

目的 探讨在前列腺特异抗原(prostate specific antigen,PSA)灰区(PSA 4～10ng/mL)患者中,血清总PSA及游离PSA比值(f/tPSA)、前列腺特异性抗原密度(PSAD)和(f/t) PSA/PSAD值对穿刺病理结果的诊断价值.方法 回顾2008年1月至2016年3月本院接受经直肠超声(transrectal ultrasound,TRUS)引导下前列腺穿刺的患者929例,对其中249例PSA 4～ 10 ng/mL患者的临床资料进行了整理分析.根据病理结果,分为前列腺癌组(PCa组)38例(15.26％),前列腺增生组(BPH组)211例(84.74％).对患者年龄、tPSA、f/tPSA、体积、PSAD、(f/t) PSA/PSAD值进行统计学分析.结果 两组患者的年龄水平比较差异无统计学意义(P＞0.05);在f/tPSA、体积、(f/t) PSA/PSAD水平,BPH组大于PCa组;在tPSA、PSAD水平,PCa组大于BPH组,差异均有统计学意义(P＜0.05).PCa组患者中f/tPSA或PSAD异常者32例,占84.21％:BPH组中f/tPSA或PSAD异常者110例,占52.13％,差异有统计学意义(X2=13.52,P ＜0.005).结论 f/tPSA和PSAD异常对PSA灰区的患者是否行前列腺穿刺具有指导意义.如果f/tPSA和PSAD结果相矛盾,f/tPSA联合PSAD、PSAD联合(f/t) PSA/PSAD的诊断价值相对较高.     

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.