Serum prostate-specific antigen as a predictor of prostate volume in men with benign prostatic hyperplasia

OBJECTIVES: To assess the utility of prostate-specific antigen (PSA) as a predictor of prostate volume by characterizing the relationship between prostate volume and serum PSA in men with symptomatic benign prostatic hyperplasia (BPH) and no evidence of prostate cancer, stratified by decade of life. METHODS: Placebo-controlled multicenter trials in patients with BPH and a safety study in normal young men provided baseline measurements of serum PSA and prostate volume. The analyses included patients with a baseline prostate volume measured by either transrectal ultrasound (TRUS) or magnetic resonance imaging and baseline serum PSA. A common central laboratory was used for all but one of the individual studies; both laboratories used the Hybritech method. Patients 80 years of age or older were excluded. Patients with a baseline serum PSA greater than 10 ng/mL were excluded to reduce the likelihood of including occult prostate cancer cases. The patients in the BPH trials were screened at baseline by digital rectal examination (DRE) and serum PSA. Those with suspicious findings underwent TRUS-guided biopsy; only patients with negative biopsies are included in these analyses. RESULTS: The analyses included 4627 patients, 4448 from the BPH trials and 179 from the safety study. The men in the BPH trials were older (mean age+SE, 63.7+0.10 years) than the men in the safety study (mean age + SE, 30.8+/-0.43), had larger prostates (mean volume+/-SE, 43.7+/-0.38 mL versus 26.3+/-0.49 mL in the safety study), and had higher serum PSA values (mean+/-SE, 2.6+/-0.03 ng/mL versus 0.7+/-0.39 ng/mL in the safety study). The relationship between prostate volume and serum PSA was evaluated using only the BPH trial data. Prostate volume and serum PSA have an age-dependent log-linear relationship (ie, their logarithms are linearly related, and the parameters of the relationship depend on age). Older men tend to have a steeper rate of increase in prostate volume with increasing serum PSA (P < 0.00 for differences between slopes), and there was a slight tendency for PSA density to increase with age. Receiver operating characteristic (ROC) curves were constructed to evaluate the ability of serum PSA to predict threshold prostate sizes in men with BPH. The ROC curve analyses revealed that PSA had good predictive value for assessing prostate volume, with areas under the curve ranging from 0.76 to 0.78 for various prostate volume cutoff points (30, 40, and 50 mL). Conclusions. Prostate volume is strongly related to serum PSA in men with BPH and no evidence of prostate cancer, and the relationship depends on age. Since treatment outcome or risk of long-term complications depend on baseline prostate volume, serum PSA can estimate the degree of prostate enlargement sufficiently accurately to be useful for therapeutic decision making. To achieve a specificity of 70% while maintaining a sensitivity between 65% and 70%, approximate age-specific criteria for detecting men with prostate glands exceeding 40 mL are PSA > 1.6 ng/mL, >2.0 ng/mL, and >2.3 ng/mL for men with BPH in their 50s, 60s, and 70s, respectively.     

经直肠超声引导下“10+X”点法前列腺穿刺活检术在PSA值介于4～20ng/ml之间患者前列腺癌诊断中的价值

目的 探讨经直肠超声引导下“10 +X”前列腺穿刺活检术在PSA值介于4 ～20ng/ml之间患者前列腺癌诊断中的价值。方法 回顾性分析226例血清PSA值介于4～20ng/ml之间疑似前列腺癌患者临床资料,所有患者均行经直肠超声引导下前列腺穿刺术活检。结果 前列腺癌47例,前列腺增生158例,前列腺炎11例,前列腺上...     

Diagnostic value of percent free prostate-specific antigen: retrospective analysis of a population-based screening study with emphasis on men with PSA levels less than 3.0 ng/mL

OBJECTIVES: To retrospectively investigate the use of percent free prostate-specific antigen (PSA) compared with total PSA in serum as predictor of prostate cancer in men selected randomly from the general population who underwent biopsy on the basis of abnormal findings on digital rectal examination (DRE) or transrectal ultrasound (TRUS) and/or serum PSA levels greater than 10 ng/mL. METHODS: A single intervention, population-based screening study was undertaken in 1988 and 1989. Of the 2400 men aged 55 to 70 years invited to participate, 1782 men responded and were examined with DRE, TRUS, and PSA testing (Tandem-Hybritech). In 1995, frozen serum samples from 1748 men were analyzed for percent free PSA (Prostatus, Wallac OY). Five-year follow-up data on new cancers in the screened population were obtained from the Swedish Cancer Registry (SCR). RESULTS: Of the 1748 men, 367 underwent TRUS-guided biopsies because of abnormal findings on either DRE or TRUS or serum PSA levels of greater than 10 ng/mL. This resulted in the diagnosis of 64 cases of prostate cancer (3.7%). PSA levels of 3.0 ng/mL or greater were found in 55 (86%) of 64 cancer cases and in 399 (24%) of the 1684 benign cases. Among the 1294 men with PSA less than 3.0 ng/mL, 9 prostate cancers were diagnosed (14% of all prostate cancers). All 9 patients with cancer and with PSA less than 3.0 ng/mL had a percent free PSA of 18% or less. In the group of 1109 patients with PSA less than 3.0 ng/mL and a percent free PSA greater than 18%, 159 biopsies were performed because of abnormal DRE or TRUS. However, no prostate cancer was diagnosed in this category of patients. Five years after the screening intervention, 7 more cases of prostate cancer were clinically diagnosed in the screened population according to the SCR. CONCLUSIONS: The combination of PSA levels less than 3.0 ng/mL and percent free PSA greater than 18% defines a large part of the population at a very low risk of cancer of the prostate both at the time of screening and during the following 5 years. Men in this group may be spared DRE, and longer screening intervals may be considered. However, the risk of having prostate cancer is not negligible in men with PSA less than 3.0 ng/mL and percent free PSA of 18% or less. The results of this study indicate that biopsy should be recommended to men fulfilling these criteria, although these results should be confirmed in larger prospective studies because of the limited number of patients with prostate cancer in the present series.     

Relationship between serum prostate-specific antigen and prostate volume in Korean men with benign prostatic hyperplasia: a multicentre study

OBJECTIVES: To evaluate the relationship between prostate specific antigen (PSA) and prostate volume (PV) in Korean men, as PV is a key predictor of both disease progression and response to medical therapy in patients with benign prostatic hyperplasia (BPH), and PSA has been suggested as a proxy marker to estimate the total PV, mainly in Caucasians. PATIENTS AND METHODS: From 1999 to 2004, men aged 50-79 years with lower urinary tract symptoms (LUTS) and BPH were enrolled into this multicentre study. The analyses included 5716 patients presenting to 11 medical centres with LUTS (International Prostate Symptom Score >8, peak urinary flow rate <15 mL/s); they had a mean age of 64.3 years, mean baseline PV of 36.9 mL, and mean baseline PSA level of 2.2 ng/mL. Men with a baseline PSA of >10 ng/mL were excluded, to reduce the likelihood of including occult prostate cancer. A biopsy was taken in those with suspicious findings on a digital rectal examination or serum PSA level of >4 ng/mL, to exclude prostate cancer. Receiver operating characteristic (ROC) curves were constructed to evaluate the ability of serum PSA to predict threshold PV in men with BPH. RESULTS: The PV and serum PSA level had an age-dependent log-linear relationship, the strength of which increased with age. The ROC curve analysis showed that PSA had good predictive value for various prostate volume thresholds (30, 40 and 50 mL). CONCLUSIONS: The PSA-PV relationship in Korean men is similar to that in Caucasians, but Korean men have a slightly lower PSA level and a smaller PV than Caucasians. The approximate age-specific criteria for detecting Korean men with a PV of >40 mL were a PSA level of >1.3 ng/mL, >1.7 ng/mL and >2.0 ng/mL for men with BPH in their sixth, seventh and eighth decade, respectively.     

RATIO OF FREE-TO-TOTAL PROSTATE SPECIFIC ANTIGEN IN SERUM CANNOT DISTINGUISH PATIENTS WITH PROSTATE CANCER FROM THOSE WITH CHRONIC INFLAMMATION OF THE PROSTATE

Purpose

We demonstrate the effect of chronic inflammation of the prostate on the ratio of free-to-total prostate specific antigen (PSA) in serum calculated as a percentage of free PSA and, therefore, that percentage of free PSA is an unspecific means to distinguish among prostate cancer, chronic prostatitis and benign prostatic hyperplasia (BPH).

Materials and Methods

Total, free and percentage of free PSA was measured in 66 men with prostate cancer, 119 with BPH and 17 with asymptomatic chronic prostatitis. In all patients the diagnosis was histopathologically confirmed by microscopic examination of prostatic specimens after sextant biopsy, transurethral prostatic resection or prostatectomy.

Results

The median values of total, free and percentage of free PSA were 4.11 micro g./l., 0.75 micro g./l. and 20.4% in patients with BPH, 10.0 micro g./l., 0.84 micro g./l. and 8.5% in those with prostate cancer, and 7.60 micro g./l., 1.23 micro g./l. and 10.6% in those with chronic prostatitis. Patients with prostate cancer and chronic prostatitis had a significantly lower percentage of free PSA than those with BPH. Receiver operating characteristics curve analysis showed that percentage of free PSA as a discriminator between prostate cancer and BPH was not suitable for differentiating between prostate cancer and chronic prostatitis.

Conclusions

Chronic prostatitis is not characterized by elevated total PSA concentrations alone but also by a decreased percentage of free PSA, a tendency similar to that in prostate cancer. This unspecific change in percentage of free PSA must be considered to interpret the percentage of free PSA correctly.     

Prediction of prostate volume based on total and free serum prostate-specific antigen: is it reliable?

OBJECTIVE: To analyze the utility of total/free prostate-specific antigen (PSA) and age as predictors of the prostate volume in men with symptomatic benign prostatic hyperplasia (BPH) and no evidence of prostate cancer. PATIENTS AND METHODS: Total and free serum PSA were determined in 681 patients with normal digital rectal examination and symptomatic BPH using the Hybritech method. Prostate volume was measured by transrectal ultrasound (TRUS). TRUS-guided biopsy was performed in 459 (67.4%) of the patients with a serum PSA >4.0 ng/ml. RESULTS: The relationship with prostate volume was best described in a log linear fashion by free PSA (R(2) = 0.367), total PSA (R(2) = 0.264) and age (R(2) = 0.017). Multiple linear regression demonstrates no significant influence of age. Free PSA was able to predict the individual TRUS prostate volume +/-10% in 67% of the patients and +/-20% in 91.2% and total PSA in 63 and 90. 9%, respectively. CONCLUSION: Prostate volume is strongly related with free and total PSA. Both determinations would be able to predict the TRUS prostate volume +/-20% in more than 90% of the patients.     

Age-specific reference levels of serum prostate-specific antigen and prostate volume in healthy Arab men

OBJECTIVE; To determine age-specific reference ranges for serum prostate-specific antigen (PSA) concentration and prostate volumes in a population of healthy Arab men. SUBJECTS AND METHODS: Blood samples were taken from 396 healthy Arab men (from Kuwait and Oman) aged 15-79 years and from across the social spectrum. Men aged >40 years had a digital rectal examination and transrectal ultrasonography of the prostate to determine prostate volume. The serum PSA level was measured using commercial kits, and age-specific ranges for PSA levels and prostate volume determined. RESULTS: The serum PSA ranges (ng/mL) for each age range in Arab men were: 40-49 years, 0-0.9; 60-69, 0-2.7; 70-79, 0-5.5 ng/mL; the respective prostate volumes were 8-22, 9-30 and 10-33 mL. The serum PSA level and prostate volume correlated with age (P < 0.001). Arab men had lower serum PSA levels and prostate volumes than those reported for Caucasians, but similar to those reported for Asians (Japanese and Chinese). CONCLUSION: These results indicate that Arab men have lower PSA levels and prostate volumes than Caucasians. The levels are slightly lower than those reported in the Japanese and, as in the Japanese, low PSA levels and small prostate volumes might be related to the low incidence of clinical prostate cancer in Arab men.     

PSAD在PSA 4～10ng患者前列腺癌诊断中的价值

目的探讨前列腺特异性抗原密度（PSAD）在前列腺特异性抗原（PSA）值介于4～10ng之间患者前列腺腺癌诊断中的应用价值。方法回顾性分析183例血清PSA值介于4～10ng之间疑似前列腺癌患者的临床资料,所有患者均经直肠B超测得前列腺体积后再行经直肠超声引导下前列腺穿刺术,通过接受者工作特征曲线分析法评价PSAD在预测诊断前列腺癌中的应用价值。结果 183例患者中36例经直肠超声下前列腺活检的患者被诊断为前列腺癌,占19.7%。良性前列腺增生组与前列腺癌患者之间,PSA（0.681 5）与PSAD（0.721 4）的曲线下方面积比较相似,而游离前列腺特异性抗原与总前列腺特异性抗原比值（f/tPSA）的曲线下面积只有0.318 2,相比PSA,PSAD值将是一个更好的预测前列腺癌的指标。结论 PSAD对于PSA值介于4～10ng/mL的中国患者是一项更好的预测前列腺癌的指标。     

Does normalizing PSA after successful treatment of chronic prostatitis with high PSA value exclude prostatic biopsy?

Objective

Evaluate male patients with diagnosed chronic prostatitis, elevated serum prostate-specific antigen (PSA) to find out whether medical treatment with antibiotics and anti-inflammatory drugs can lower serum PSA, and consequently decrease the prostate cancer detection rate in patients with post-treatment PSA<4 ng/mL.

Materials and methods

This prospective study evaluated 142 male patients aged 40-73 years whose presented with elevated serum PSA>4 ng/mL and were consequently diagnosed with chronic prostatitis as expressed prostatic excretions examination revealed more than 10 white blood cells per high power field. The Patients underwent treatment with antibiotics and nonsteroidal anti-inflammatory agents for 6-weeks. Subsequently, all patients are Followed-up by serum PSA and performed transrectal ultrasonography-guided prostate biopsy within 2 months of treatment.

Results

Mean patient age was (54.4±13.5) years. The mean PSA pretreatment was (8.11±3.7) ng/mL and after treatment, the mean PSA denoted a significant decrease to (4.7±3.5) ng/mL (P=0.002). The percent of changes in mean PSA was 41.9%. Prostatic biopsy after treatment showed that, cancer prostate in 31 patients (21.8%), chronic prostatitis in 71 patients (50.7%), chronic prostatitis plus benign prostatic hyperplasia (BPH) in 31 (21.8%) and BPH in 9 patients (6.3%) With regard to PSA values, cancer prostate patients were 3/25 (12%) if PSA<2.5 ng/mL, 6/47 (12.7%) if 4.0>PSA≥2.5 and 21/70 (30%) if PSA≥4.0. The numbers of cancer prostate detected patients were 30 (21.1%).

Conclusions

Chronic prostatitis is one of the causes that elevate serum PSA levels. Treatment of chronic prostatitis with elevated PSA by antibiotics and anti-inflammatory agents can decrease the elevated PSA to the normal levels. Nevertheless, the opportunities of potential prostate cancer still exist in patients with a decreased PSA level even also if PSA<2.5 ng/mL.     

游离前列腺特异抗原百分率检测前列腺癌的临床观察

目的 评价游离前列腺特异抗原（ＰＳＡ）百分率（Ｆ／Ｔ百分率）检测前列腺癌的临床价值。方法 用免疫放射法测定１１７例血清游离ＰＳＡ（Ｆ－ＰＳＡ）、总ＰＳＡ（Ｔ－ＰＳＡ）值,并计算游离ＰＳＡ所占百分率（Ｆ／Ｔ百分率）值;其中前列腺癌３１例,前列腺肥大８６例。结果 Ｆ／Ｔ百分率值在前列腺癌组明显低于前列腺肥大组（Ｐ〈０．０１）;若总ＰＳＡ限定于４￣１０ｎｇ／ｍｌ范围内,应用Ｆ／Ｔ百分率值可区别前列腺癌与     

Effect of NIH-IV prostatitis on free and free-to-total PSA

OBJECTIVE: To examine the effect of asymptomatic prostatic inflammation (NIH category IV prostatitis) on total PSA (tPSA), free serum PSA (fPSA) and the ratio of free-to-total prostate specific antigen (%fPSA). The role of free and %fPSA as a diagnostic tool for distinguishing between cancer and non-malignant diseases of the prostate was also investigated. MATERIAL AND METHODS: In a retrospective study 1090 prostate biopsies performed between January 2000 and September 2003 were evaluated and the levels of serum total and free PSA as well as the f/tPSA ratio were determined in samples obtained immediately before biopsy. 404 patients with full clinical and histological records were included in the study. All patients underwent 6 or 8 core primary prostate needle biopsies. RESULTS: A total of 404 patients were included in the analysis. 100 prostate cancer (PCa) (24.8%), 137 NIH-IV prostatitis (33.9%) and 143 patients with benign prostatic hyperplasias (BPH) (35.4%) were identified. 24 (5.9%) patients presented with both PCa and prostatitis on histology and were excluded from further analysis. The mean (median) levels of tPSA, fPSA and %fPSA were 11.94 ng/ml (8.0), 1.31 ng/ml (1.07) and 0.15 (0.14) for NIH-IV prostatitis; 11.94 ng/ml (8.35), 1.54 ng/ml and 0.13 (0.11) for prostate cancer; and 8.19 ng/ml (7.0), 1.48 ng/ml (1.03) and 0.18 (0.15) for BPH. No significant difference was found in tPSA levels between PCa and prostatitis (p = 0.32), while the difference in tPSA levels between PCa and BPH was significant (p = 0.007). Free PSA alone had no diagnostic power in distinguishing PCa from prostatitis (p = 0. 37) and BPH (p = 0. 61). By contrast, the f/tPSA ratio showed significant between-group differences (PCa versus prostatitis (p = 0. 011), PCa versus BPH (p = 0.0001). CONCLUSIONS: Chronic asymptomatic prostatitis NIH category IV has similar effects on total PSA and free PSA levels in serum as PCa. fPSA alone cannot distinguish prostate cancer from non-malignant inflammatory disease of the prostate. The ratio of free-to-total PSA is significantly different in PCa and NIH category IV prostatitis.     

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.     

Urinary PSA: a potential useful marker when serum PSA is between 2.5 ng/mL and 10 ng/mL

Introduction

Our objective was to evaluate the usefulness of urinary prostate specific antigen (PSA) in the differential diagnosis of benign prostatic hyperplasia (BPH) and prostate cancer.

Methods

We undertook a prospective study and obtained informed consent from 170 men. They provided blood samples to measure serum PSA and 50 mL of first-voided urine to measure urinary PSA. Seventy-seven men were diagnosed with BPH; 42 patients had newly diagnosed prostate cancer; and 51 were selected as age-matched control subjects. Data were analyzed using Wilcoxon signed rank tests, receiver operating characteristic (ROC) curves and logistic regression.

Results

Prostate volume was 35 cm³ and 45 cm³ (p < 0.05), serum PSA was 9.7 ng/mL and 4.5 ng/mL (p < 0.001) and PSA density was 0.28 and 0.11 (p < 0.01) for prostate cancer and BPH patients, respectively. Overall, urinary PSA was not significantly different, but PSA ratio (urinary:serum) was significantly different at 6.7 and 30.6 (p < 0.001) for prostate cancer and BPH patients, respectively. A subgroup with serum PSA between 2.5 ng/mL and 10.0 ng/mL was selected and urinary PSA was significant: 52.6 ng/mL (n = 29) and 123.2 ng/mL (n = 35) (p < 0.05) for prostate cancer and BPH patients, respectively. PSA ratios were also significant (p = 0.007). ROC curves identified a cutoff for urinary PSA at > 150 ng/mL, with a sensitivity of 92.5%. When comparing prostate cancer patients with age-matched control subjects, serum PSA, urinary PSA and PSA ratio were different (p = 0.004).

Conclusion

Our study supports urinary PSA as a useful marker in the differential diagnosis of prostate cancer and BPH, especially when serum PSA is between 2.5 ng/mL and 10 ng/mL. Low urinary PSA and PSA ratios point toward prostate cancer. A urinary PSA threshold of > 150 ng/mL may be used to decrease the number of prostatic biopsies.     

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.     

Clinicopathological Features of Prostate Cancer Detected by Transrectal Ultrasonography-Guided Systematic Six-Sextant Biopsy

Background :
The objectives of this study were to compare the efficacy of 3 modalities (prostate-specific antigen (PSA) assay, digital rectal examination (DRE), and transrectal ultrasonography (TRUS)) in detecting prostate cancer which was pathologically confirmed by TRUS-guided systematic six-sextant biopsy, and to investigate the relationship between the number of positive cores and several clinicopathological parameters.
Methods :
Between 1 992 and 1994, 297 males (155 from a mass screening program and 142 identified as outpatients) with a mean age of 71 years, underwent examinations including PSA determination, DRE, TRUS and systematic six-sextant biopsy, and/or additional directed biopsy.
Results :
Prostate cancer was detected in 93 men. The sensitivity level of the PSA assay was significantly higher (85%) than that of either DRE or TRUS. Patients with an abnormal DRE or TRUS, elevated PSA levels, and those in the T3-T4 category or with moderate to poorly-differentiated adenocarcinomas had more positive biopsy cores (P< 0.05). Also, the relationships of both the number of positive biopsy cores and tumor grade to bone metastasis were significant (P < 0.01). Of 209 hypoechoic areas identified by transrectal ultrasonography, 42% were cancerous, and of 427 isoechoic areas, 1 2% were cancerous. The percentage of positive biopsy cores with hypoechoic areas was 86% in the subjects with a PSA > 10 ng/mL, but low (9%) in subjects with a PSA < 4 ng/mL, and the percentage of negative biopsy cores with a normal TRUS was high (98%) in subjects with a PSA of < 4 ng/mL, but lower (67%) in subjects with a PSA > 10 ng/mL.
Conclusion :
The serum PSA assay was more useful than either DRE or TRUS in detecting prostate cancer. The percentage of bone metastasis increased concomitant with the number of positive biopsy cores, and the positive biopsy rate of hypoechoic areas positively correlated with the PSA level.     

Significance of histological prostatitis in patients with urinary retention and underlying benign prostatic hyperplasia or adenocarcinoma of the prostate

What's known on the subject? and What does the study add? It is known that histological prostatitis is associated with a significantly higher risk for acute urinary retention in men with BPH. This study showed that, in men with BPH, histological prostatitis was associated with urinary retention at a significantly younger age and with higher serum PSA levels. In men with ACP, histological prostatitis was associated with urinary retention at an earlier stage of cancer. Study Type – Prognosis (individual cohort) Level of Evidence 2b

OBJECTIVE

• ? To compare the clinical features of patients having urinary retention and benign prostatic hyperplasia (BPH) with those having adenocarcinoma of the prostate (ACP) and to evaluate the significance of histological prostatitis.

PATIENTS AND METHODS

• ? The clinical data and histopathology reports of patients with retention admitted to Tygerberg Hospital between September 1998 and June 2007 were evaluated.
• ? Statistical analysis was performed with Student's t‐test, Mann–Whitney test and Fisher's exact test where appropriate and P < 0.05 was considered to indicate statistical significance.

RESULTS

• ? Prostatic histology was available in 405 patients, 204 with BPH and 201 with ACP.
• ? Comparing those with BPH and those with ACP showed statistically significant differences in mean age (69.5 vs 71.9 years), serum prostate‐specific antigen (PSA) level (18.6 vs 899.5 ng/mL) and histological prostatitis (48 vs 25%) but not duration of catheterization, prostate volume or urinary tract infection (UTI).
• ? Comparing those with BPH only and those with BPH plus prostatitis showed significant differences in mean age (71.9 vs 67.1 year) and PSA level (14.6 vs 22.8 ng/mL) but not prostate volume, UTI or duration of catheterization.
• ? Comparing those with ACP only and those with ACP plus prostatitis showed significant differences in stage T4 cancer (68.1 vs 35.4%) and PSA level (1123.4 vs 232.4 ng/mL) but not age, prostate volume, UTI or duration of catheterization.

CONCLUSIONS

• ? Histological prostatitis was almost twice as common in patients with urinary retention associated with underlying BPH than in patients with ACP, but there was no significant difference in the duration of catheterization, prostatic volume or presence of UTI, suggesting that histological prostatitis more often contributes to the development of retention in patients with underlying BPH than in those with ACP.
• ? In patients with BPH, histological prostatitis was associated with urinary retention at a significantly younger age and with higher serum PSA levels.
• ? In patients with ACP, histological prostatitis was associated with urinary retention at an earlier stage of cancer.

     

Utility of Volume Adjusted Prostate Specific Antigen Density in the Diagnosis of Prostate Cancer in Arab Men

Background: This study was undertaken to assess the utility of prostate specific antigen (PSA) and PSA density (PSAD) in discriminating between benign and malignant prostate disease in the Kuwaiti Arab population.Methods: A total of 100 consecutive patients suspected of having prostate cancer because of serum PSA > 4 ng/ml, or detection of a prostatic nodule on rectal examination were further investigated by determination of PSAD, TRUS of prostate, sexant prostatic biopsy and histological analysis to establish the correct diagnosis. Other diagnostic measures included the determination of the area under the receiver operating characteristic (ROC) curve, sensitivity and specificity. Results: Of the 100 prostate biopsies that were performed, 33 cases were confirmed to be prostate cancer and 67 were described as benign lesions comprising benign prostatic hyperplasia (BPH) with or without prostatitis. The age range for patients with prostate cancer was 42–90 years, and 52–90 years for those without prostate cancer. The mean prostate volume was 58.82 cc (range 9–177 cc) and 62.60 cc (range 15–140 cc), the mean PSA value was 36.65 ng/ml (range 5.8–200 ng/ml) and 16.49 ng/ml (range 1.4–46.0 ng/ml), while the mean PSAD was 0.92 (range 0.046–5.714) and 0.452 (range 0.034–2.294) for patients with prostate cancer and patients without prostate cancer respectively. Patients with PSA less than 4 ng/ml (3 cases) all had benign prostate lesions, and 7 cases with PSA more than 50 ng/ml all had prostate cancer and were excluded because values above 50 ng/ml have close to 100% specificity for prostate cancer. Further analysis was done on the remaining 90 cases which were patients with a PSA between 4 and 50 ng/ml. The discriminating power of serum PSA for detecting prostate cancer as estimated by the area under ROC was 0.686 while that for PSAD was 0.732. The maximum likelihood for a positive PSA was at a PSAD cut-off point of 0.32. For the PSA cut-off point of l0 ng/ml, the sensitivity was 80%, and specificity was 42.2%. For the PSAD cut-off point of 0.32, the sensitivity was 58% and the specificity 76.6%. Conclusions: Determination of PSAD is not a useful adjunct to serum PSA values in the range of 10–50 ng/ ml in our population. PSAD value less than 0.32 with PSA less than l0 ng/ml strongly suggests benign disease.     

Measurement of serum zinc improves prostate cancer detection efficiency in patients with PSA levels between 4 ng/mL and 10 ng/mL

Aim： To investigate whether the measurement of serum zinc may improve the detection of prostate cancer （PCa） in men who had total prostate-specific antigen （PSA） levels higher than 4.1 ng/mL. Methods： A mass screening for PCa of 3940 men over 50 years old was undertaken using total serum PSA. Of the 190 men （4.8 %） with elevated PSA, 143 （3.6 %） underwent a transrectal ultrasonography （TRUS）-guided biopsy of the prostate, and 42 men （1% of total and 29.3 % of men undergoing biopsy） were found to have cancer. The areas under the receiver operating characteristic curves （ROC-AUC） were used to compare the diagnostic power of cancer detection by means of serum zinc, and free PSA/total PSA ratio （fit）. Results： The men with levels of serum zinc that ranged from 40 ng/mL-60 ng/mL, had an age-adjusted odds ratios（OR） of 5.0. A cutoff value of 100 gg/mL for-serum zinc concentration provided a sensitivity of 90.5 % and a specificity of 32.7 % in elevated PSA range, and a sensitivity of 93.3 % and specificity of 27.1% in gray zone, respectively. In the gray zone ranges of 4.1 ng/mL-10.0 ng/mL, the ROC-AUC for zinc was 73.0 % higher than 62.7 % of f/t PSA ratio and 56.7 % of total PSA. Conclusion： PCa displays a lower serum zinc concentration. The measurement of zinc levels improves PCa detection in the gray zone compared with the f/t PSA ratio and total PSA. （Asian J Androl 2005 Sep; 7： 323-328）     

Population-based screening for prostate cancer by measuring total serum prostate-specific antigen in Iran

OBJECTIVE: To report the results from an Iranian large population-based randomized study of screening using prostate-specific antigen (PSA) to detect prostate cancer. MATERIALS AND METHODS: A total of 3758 Iranian men older than 40 years were mass checked by PSA-based screening. Men with an abnormal digital rectal examination (DRE) and serum total PSA level of greater than 4 ng/mL, underwent transrectal ultrasonography (TRUS)-guided extended prostate biopsy. RESULTS: The PSA value (mean +/- standard deviation, SD) in all men without prostate cancer was 1.6 +/- 1.1 ng/mL and in those with cancer 18 +/- 44.8 ng/mL (P = 0.001). PSA values increased with age. In those aged 40-49, 50-59, 60-69 and > or = 70 years, the mean +/- SD PSA values were 1.3 +/- 0.7, 1.4 +/- 0.8, 1.8 +/- 1 and 2.2 +/- 1.6 ng/mL, respectively. Among the screened men, 323 (8.6%) had a serum PSA concentration greater than 4 ng/mL. Of patients who underwent prostate biopsy (230, 71.2%), 129 (positive predictive value, 56.1%) had prostate cancer. Additionally, nine cancers were detected among 16 patients with PSA of less than 4 ng/mL who had a doubtful DRE finding. The overall cancer detection rate was 3.6%; 1.4% at 40-49, 1.6% at 50-59, 4.2% at 60-69 and 12.9% at >/=70 years. Conventional systematic sextant biopsies, which accounted for six of the 10 cores in our biopsy scheme, detected 98 (71%) of the cancers. CONCLUSIONS: The Iranian male population develops prostate cancer quite commonly if their serum PSA levels are greater than 4.0 ng/mL. In this study, 65.9% of the detected cancers were clinically significant. The conventional systematic sextant technique may be inappropriate for detection of all prostate cancers. The results need to be confirmed in other randomized trials.     

A comparison of the free fraction of serum prostate specific antigen in men with benign and cancerous prostates: the best case scenario

Purpose

In most previous studies of free-to-total serum prostate specific antigen (PSA) ratios, the specimens from patients with prostate cancer or those with benign prostatic hyperplasia (BPH) have not been highly characterized. We compared preoperative sera from post-radical prostatectomy patients with clinically significant cancers of at least 2 cm.³ to sera from those with BPH and large, biopsy negative prostates.

Materials and Methods

We used 2 different time resolved immunofluorometric assays for free and total PSA, and a combination of a chemoluminescent immunoassay for free PSA detection with an immunoradiometric assay for total PSA to measure free and total PSA. The serum ratios of free-to-total PSA in these assays were compared to those obtained previously from gel filtration studies. Sera from 51 men with prostate cancer volumes of 2 to 18 cm.³ were compared to those from 48 men with BPH and a mean prostate volume of 78 plus/minus 7 cm.³. The respective mean serum PSA levels plus or minus standard deviation were 10.0 plus/minus 6.3 and 8.9 plus/minus 7.2 ng./ml.

Results

Monoclonal assays for free PSA confirmed the previous study with gel filtration. For PSA 4 to 10 ng./ml., 94 to 95 percent of the men with prostate cancer were correctly diagnosed, with a cutoff of less than 15 percent for free-to-total PSA on immunofluorometric assay and less than 14 percent for chemoluminescent immunoassay with immunoradiometric assay. However, 46 percent (immunofluorometric assay) and 36 percent (chemoluminescent immunoassay and immunoradiometric assay) of men with BPH did not have enough free PSA for diagnosis of BPH (that is 36 to 46 percent false-positive rate).

Conclusions

For total PSA 4 to 10 ng./ml., the sensitivity of approximately 15 percent free-to-total PSA for prostate cancer is high (94 to 95 percent) but 36 to 46 percent of men with BPH and a large gland will not be correctly identified. For PSA 2 to 4 ng./ml., no ratio of percent free-to-total PSA discriminated BPH from prostate cancer.