Correlation between serum prostate specific antigen levels and the volume of the individual glandular zones of the human prostate

Apparent differences in prostate zones: susceptibility to prostate cancer, benign prostatic hyperplasia and prostatitis

Men are inevitably plagued by prostate disease throughout their lives. However, the understanding of the pathogenesis of prostate diseases is still limited. In the 1960s, McNeal proposed the theory of prostate zones: the prostate was divided into three main zones: transition zone, central zone, and peripheral zone. Over the past 50 years, significant differences between different prostate zones have been gradually revealed. We summarized the most significant differences in different zones of the prostate. For the first time, we proposed the "apparent difference in prostate zones" concept. This new concept has been proposed to understand the different zones of the prostate better. It also provided new ideas for exploring the susceptibility of lesions in different prostate zones. Despite the reported differences between zones, the treatment of prostate-related diseases remains partition agnostic. Therefore, we also discussed the clinical significance of the "apparent difference in the prostate zone" and emphasized the necessity of prostate zones.

Significance of the prostate central gland and total gland volume ratio in the diagnosis of prostate cancer patients in the prostate specific antigen grey zone

Objective

To explore the significance of the prostate central gland to total gland volume ratio (PVc/PV) in the diagnosis of prostate cancer (PCa) in patients with prostate specific antigen (PSA) levels in the grey zone (4–10 ng/ml).

Methods

This retrospective study enrolled patients that had undergone prostate biopsy. The volume of the prostate and the central prostate gland were measured. The differences in PSA, the ratio of free to total PSA (f/tPSA), PSA density (PSAD) and PVc/PV between the PCa and non-PCa groups were compared. Receiver operating characteristic curve analysis for PCa and clinically significant PCa (csPCa) diagnosis were calculated according to PSA (reference), f/tPSA, PSAD and PVc/PV.

Results

This study enrolled 136 patients. There was no significant difference in PSA and f/tPSA between the PCa and non-PCa groups, while there were significant differences in PSAD and PVc/PV. The area under the curve values of PVc/PV for PCa or csPCa diagnosis were 0.876 and 0.933, respectively; and for PSAD, they were 0.705 and 0.790, respectively. These were significantly different compared with the PSA curve, whereas f/tPSA showed no significant difference from the PSA curve.

Conclusion

PVc/PV could be a predictor of PCa when PSA is between 4–10 ng/ml.

Effect of prostate volume on f/tPSA value: A cross-sectional study

Previous studies have suggested that there is a positive correlation between prostate-specific antigen (PSA) levels and prostate volume (PV). A better understanding of the possible influence of PV on a ratio of free to total PSA (f/tPSA) may improve the diagnostic value of the prostate disease. The study group consisted of 342 men with lower urinary tract symptoms (LUTS). All patients underwent urinary tract ultrasonography and had tests carried out on PSA, serum glucose, total cholesterol, triglyceride, HDL, LDL and blood pressure. Univariate and multivariate analyses were used to assess the associations between prostate volume and f/tPSA value. We found no obvious relationship between prostate volume and f/tPSA value when PSA >10 ng/ml but did observe a positive correlation when 4 ng/ml < PSA ＜ 10 ng/ml (hazard ratio [HR]: 0.0012; 95% confidence interval [CI]: 0.0009-0.0248). With increasing prostate volume, multivariate analysis showed an obvious increase in f/tPSA value (HR: 0.0011; 95% CI: 0.0007-0.0015) (p ≤ .0001). We confirmed that prostate volume could affect the f/tPSA levels in serum. There was an obvious positive correlation between prostate volume and f/tPSA level when PSA levels were between 4 and 10ng/dl. There was no significant correlation between prostate volume and f/tPSA value when PSA >10 ng/ml.

The role of the androgen receptor in prostate development and benign prostatic hyperplasia: A review

Benign prostatic hyperplasia (BPH) is a benign enlargement of the prostate in which incidence increases linearly with age, beginning at about 50 years old. BPH is a significant source of morbidity in aging men by causing lower urinary tract symptoms and acute urinary retention. Unfortunately, the etiology of BPH incidence and progression is not clear. This review highlights the role of the androgen receptor (AR) in prostate development and the evidence for its involvement in BPH. The AR is essential for normal prostate development, and individuals with defective AR signaling, such as after castration, do not experience prostate enlargement with age. Furthermore, decreasing dihydrotestosterone availability through therapeutic targeting with 5α-reductase inhibitors diminishes AR activity and results in reduced prostate size and symptoms in some BPH patients. While there is some evidence that AR expression is elevated in certain cellular compartments, how exactly AR is involved in BPH progression has yet to be elucidated. It is possible that AR signaling within stromal cells alters intercellular signaling and a "reawakening" of the embryonic mesenchyme, loss of epithelial AR leads to changes in paracrine signaling interactions, and/or chronic inflammation aids in stromal or epithelial proliferation evident in BPH. Unfortunately, a subset of patients fails to respond to current medical approaches, forcing surgical treatment even though age or associated co-morbidities make surgery less attractive. Fundamentally, new therapeutic approaches to treat BPH are not currently forthcoming, so a more complete molecular understanding of BPH etiology is necessary to identify new treatment options.

Tumour innervation and neurosignalling in prostate cancer

Prostate cancer progression has been shown to be dependent on the development of autonomic nerves into the tumour microenvironment. Sympathetic nerves activate adrenergic neurosignalling that is necessary in early stages of tumour progression and for initiating an angiogenic switch, whereas parasympathetic nerves activate cholinergic neurosignalling resulting in tumour dissemination and metastasis. The innervation of prostate cancer seems to be initiated by neurotrophic growth factors, such as the precursor to nerve growth factor secreted by tumour cells, and the contribution of brain-derived neural progenitor cells has also been reported. Current experimental, epidemiological and clinical evidence shows the stimulatory effect of tumour innervation and neurosignalling in prostate cancer. Using nerves and neurosignalling could have value in the management of prostate cancer by predicting aggressive disease, treating localized disease through denervation and relieving cancer-associated pain in bone metastases.

Impact of PSA density of transition zone as a potential parameter in reducing the number of unnecessary prostate biopsies in patients with psa levels between 2.6 and 10.0 ng/mL

Purpose:

To assess the accuracy of prostate-specific antigen (PSA) adjusted for the transition zone volume (PSATZ) in predicting prostate cancer by comparing the ability of several PSA parameters in predicting prostate cancer in men with intermediate PSA levels of 2.6 – 10.0 ng/mL and its ability to reduce unnecessary biopsies.

Materials and Methods:

This study included 656 patients referred for prostate biopsy who had a serum PSA of 2.6 – 10.0 ng/mL. Total prostate and transition zone volumes were measured by transrectal ultrasound using the prolate ellipsoid method. The clinical values of PSA, free-to-total (F/T) ratio, PSA density (PSAD) and PSATZ for the detection of prostate cancer were calculated and statistical comparisons between biopsy-positive (cancer) and biopsy-negative (benign) were conducted.

Results:

Cancer was detected in 172 patients (26.2%). Mean PSA, PSATZ, PSAD and F/T ratio were 7.5 ng/mL, 0.68 ng/mL/cc. 0.25 ng/mL/cc and 0.14 in patients with prostate cancer and 6.29 ng/mL, 0.30 ng/mL/cc, 0.16 ng/mL/cc and 0.22 in patients with benign biopsies, respectively. ROC curves analysis demonstrated that PSATZ had a higher area under curve (0,838) than F/T ratio (0.806) (P<0.001) and PSAD (0.806) (P<0.001). With a cut-off value of 0.22 ng/mL/cc, PSATZ had 100% of sensitivity and could have prevented 24% of unnecessary biopsies.

Conclusions:

PSATZ may be useful in enhancing the specificity of serum PSA. Compared to other PSA related parameters, it was better in differentiating between prostate cancer and benign prostatic enlargement. Also, PSATZ could reduce a significant number of unnecessary biopsies.

Clinical Considerations for Intravesical Prostatic Protrusion in the Evaluation and Management of Bladder Outlet Obstruction Secondary to Benign Prostatic Hyperplasia

Background

Intravesical prostatic protrusion (IPP) is a manifestation of benign prostatic hyperplasia marked by overgrowth of the prostatic median lobe into the bladder, producing bladder outlet obstruction and related storage and voiding symptoms.

Methods

A MEDLINE® database search of the current literature was guided using combination of "prostate" with the following terms: intravesical prostatic protrusion, bladder trabeculation, bladder outlet obstruction, lower urinary tract symptoms, alpha blockers, transrectal ultrasonography, and prostatectomy.

Results

Although IPP can be identified via a variety of imaging modalities, it is easily detected via transrectal ultrasonography (TRUS). Failing to detect IPP promptly by TRUS may result in refractory symptoms of benign prostatic hyperplasia, as the condition may not respond to typical α₁-adrenoceptor antagonist therapy. In addition, depending on grade, IPP can influence outcomes and complications of prostatectomies.

Conclusion

Upon report of lower urinary tract symptoms, initial performance of TRUS along with digital rectal examination prevents delay in the appropriate evaluation and management of prostatic diseases.

Prostate specific antigen and acinar density: a new dimension, the "Prostatocrit"

Background

Prostate-specific antigen densities have limited success in diagnosing prostate cancer. We emphasise the importance of the peripheral zone when considered with its cellular constituents, the “prostatocrit”.

Objective

Using zonal volumes and asymmetry of glandular acini, we generate a peripheral zone acinar volume and density. With the ratio to the whole gland, we can better predict high grade and all grade cancer. We can model the gland into its acinar and stromal elements. This new “prostatocrit” model could offer more accurate nomograms for biopsy.

Materials and Methods

674 patients underwent TRUS and biopsy. Whole gland and zonal volumes were recorded. We compared ratio and acinar volumes when added to a “clinic” model using traditional PSA density. Univariate logistic regression was used to find significant predictors for all and high grade cancer. Backwards multiple logistic regression was used to generate ROC curves comparing the new model to conventional density and PSA alone.

Outcome and results

Prediction of all grades of prostate cancer: significant variables revealed four significant “prostatocrit” parameters: log peripheral zone acinar density; peripheral zone acinar volume/whole gland acinar volume; peripheral zone acinar density/whole gland volume; peripheral zone acinar density. Acinar model (AUC 0.774), clinic model (AUC 0.745) (P=0.0105). Prediction of high grade prostate cancer: peripheral zone acinar density (“prostatocrit”) was the only significant density predictor. Acinar model (AUC 0.811), clinic model (AUC 0.769) (P=0.0005).

Conclusion

There is renewed use for ratio and “prostatocrit” density of the peripheral zone in predicting cancer. This outperforms all traditional density measurements.

Transition zone prostate specific antigen density improves prostate cancer detection in Iranian men

Background:

Prostate specific antigen (PSA) as a tumor marker has extensively changed the diagnosis of prostate cancer (PCa). With the advent of PSA, the majority of patients are diagnosed with nonpalpable early stage PCa. However, PSA lacks specificity and many patients undergo unnecessary biopsies due to an elevated serum PSA level.

Objectives:

This study aimed to assess the sensitivity and specificity of transition zone PSA density (TZPSAD) in detection of PCa.

Patients and Methods:

This study was performed on 1712 men underwent trans-rectal ultrasound guided prostate biopsy in our institution between March 2008 and March 2013. A total of 1120 men with PSA < 20 ng/mL and normal digital rectal exam were selected for evaluation. Transition zone PSA density was calculated in all patients and the receiver operating characteristic (ROC) curve was used to analyze the accuracy of TZPSAD for the diagnosis of PCa.

Results:

Among 1120 men who were eligible for enrolment, prostate cancer was detected in 265 patients. Mean serum PSA levels were 9.7 ± 4.3 ng/mL and 8.5 ± 3.7 ng/mL in patients with and without PCa, respectively (P < 0.001). Mean value for TZPSAD was 1.18 ± 1.19 ng/mL/mL in patients with PCa, whereas it was 0.55 ± 0.84 ng/mL in men without cancer (P < 0.001). Optimal cut-off value for TZPSAD was 0.32 ng/mL. At this cut-off value, the sensitivity and specificity values for TZPSAD were 85% and 45%, respectively. Applying the TZPSAD for PCa screening decreased 50% of unnecessary biopsies.

Conclusions:

Using TZPSAD as an adjunct to PSA may improve the specificity of PSA in the diagnosis of PCa and decrease the number of unnecessary prostatic biopsies in Iranian men with serum PSA level < 20 ng/mL.

A new model consists of intravesical prostatic protrusion, prostate volume and serum prostatic-specific antigen in the evaluation of prostate cancer

The Prostate-specific antigen (PSA) level is largely used to diagnose prostate cancer (PCa) in last decades. However, its specificity is low in patients with a PSA level ranging from 4.0 to 10.0 ng/ml. This study aims to define the correlation between intravesical prostatic protrusion (IPP) and PSA and to establish a new model to predict PCa. A total of 339 patients order than 45 years examined between October 2010 and June 2012 were enrolled. Eligible patients were recommended for transrectal ultrasonography (TRUS)-guided prostate biopsies after measuring total prostate volume (TPV), tranzisional zone volume (TZV) and IPP. The levels of total PSA (tPSA), free PSA (fPSA) were analyzed by using Hybritech calibrated Access tPSA and fPSA assays. A new mathematical model, named IPP removed PCa predicting score (IRPPS), consists of tPSA, TZV and IPP was established. The predictive accuracy of IRPPS, PSA density (PSAD), %PSA and tPSA were compared using receiver-operator characteristic (ROC) analysis. Eighty-six patients had PSA levels of 4.0-10.0 ng/ml. Twenty of them were diagnosed as PCa. Using ROC curves, the areas under the curve for IRPPS, PSAD and %PSA and tPSA were 0.786, 0.768 and 0.664 and 0.585, respectively. We suggested IPP grade had a significant relationship with serum tPSA levels. The predictive accuracy of IRPPS was higher than the other 3 indictors.

Performance of prostate-specific antigen mass in estimation of prostate volume in Japanese men with benign prostate hyperplasia

OBJECTIVES

Obese men with benign prostate hyperplasia might have lower serum prostate-specific antigen because of hemodilution, resulting in underestimation of total prostate volume by serum prostate-specific antigen. The aim of this study was to compare the performance of prostate-specific antigen mass as the absolute amount of prostate-specific antigen protein secreted into circulation with that of serum prostate-specific antigen in the prediction of total prostate volume.

METHODS

A total of 1517 men with serum prostate-specific antigen up to 10 ng/mL, including 1425 with biopsy-proven benign prostate hyperplasia, were enrolled in this study. Height and weight were used to estimate body mass index, body surface area and plasma volume. Prostate-specific antigen mass was calculated as serum prostate-specific antigen multiplied by plasma volume. The association between serum prostate-specific antigen or prostate-specific antigen mass and transrectal ultrasound-measured total prostate volume were evaluated by Pearson's correlation coefficient (Υ), linear regression analyses and receiver operating characteristic curves.

RESULTS

Serum prostate-specific antigen had an inverse relationship with plasma volume, decreasing as plasma volume increased, after adjustment of total prostate volume. Larger total prostate volume per serum prostate-specific antigen was found in men with higher body mass index or plasma volume. Among all participants, the correlation (Υ = 0.456) between prostate-specific antigen mass and total prostate volume was apparently stronger than that (Υ = 0.442) between serum prostate-specific antigen and total prostate volume. Prostate-specific antigen mass outperformed serum prostate-specific antigen at estimating total prostate volume cut-off values of 30 and 40 mL. These findings were more significant in men aged ≥60 years.

CONCLUSIONS

Prostate-specific antigen mass performs better than serum prostate-specific antigen in estimating TPV, especially in men aged ≥60 years.

The ability of prostate-specific antigen (PSA) density to predict an upgrade in Gleason score between initial prostate biopsy and prostatectomy diminishes with increasing tumour grade due to reduced PSA secretion per unit tumour volume

Study Type - Diagnostic (exploratory cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Due to sampling error, the Gleason score of clinically localized prostate cancer is frequently underestimated at the time of initial biopsy. Given that this may lead to inappropriate surveillance of patients with high-risk disease, there is considerable interest in identifying predictors of significant undergrading. Recently PSAD has been proposed to be an accurate predictor of subsequent upgrading in patients diagnosed with Gleason 6 disease on biopsy. We examined the predictive characteristics of PSAD in patients with low- and intermediate-risk disease on biopsy subsequently treated with radical prostatectomy. We found that although PSAD was a significant predictor of upgrade of biopsy Gleason 6 and 3 + 4 = 7 tumours, it failed to predict upgrading in patients with Gleason 7 tumours taken as a whole. When we explored reasons for this discrepancy, we found that the amount of PSA produced per unit tumour volume decreased with increasing Gleason score, thereby diminishing the predictive value of PSAD.

OBJECTIVES

To analyse the performance of PSA density (PSAD) as a predictor of Gleason score upgrade in a large cohort stratified by Gleason score. We and others have shown that an upgrade in Gleason score between initial prostate biopsy and final radical prostatectomy (RP) pathology is a significant risk factor for recurrence after local therapy.

PATIENTS AND METHODS

Patients undergoing RP with matching biopsy information were identified from two prospective databases. Patients were analysed according to the concordance between biopsy and final pathology Gleason score in three paired groups: 6/>6, 3 + 4/>3 + 4, 7/>7. Receiver-operating characteristic (ROC) curves were generated stratified by Gleason score, and the area under the curve (AUC) calculated. Logistic regression models were fitted to identify significant predictors of tumour upgrade.

RESULTS

From 1516 patients, 435 (29%) had an upgrade in Gleason score. ROC analysis showed a decline in AUC with increasing biopsy Gleason score, from 0.64 for biopsy Gleason score 6, to 0.57 for Gleason score 7. In logistic regression models containing pretreatment variables, e.g. clinical stage and number of positive cores, for Gleason score 6 and 3 + 4, PSAD was the strongest predictor of subsequent tumour upgrade (odds ratio [OR] 1.46, 95% confidence interval [95% CI] 1.18-1.83, P= 0.001 and OR 1.37, 95% CI 1.14-1.67, P= 0.002, respectively). Surprisingly, in tumours upgraded from Gleason score 7 to >7, PSAD was not predictive even on univariable analysis, whereas clinical stage and number of positive cores were significant independent predictors. To explore the relationship between serum PSA and Gleason score, tumour volume was calculated in 669 patients. There was a strong association between Gleason score and tumour volume, with the median volume of Gleason score 7 and Gleason score >7 tumours being approximately twice and four-times that of Gleason score 6 tumours, respectively (P < 0.001). In contrast, the median serum PSA level per millilitre tumour volume decreased significantly with increasing grade, from 5.4 ng/mL for Gleason score 6 to 2.1 ng/mL for >7 (P < 0.001).

CONCLUSIONS

There is a strong correlation between Gleason score and tumour volume in well/intermediate differentiated tumours, and as they produce relatively high amounts of PSA per unit volume of cancer, high PSAD is the strongest single predictor of tumour undergrading. However, as higher grade tumours produce less PSA per unit volume, PSAD loses its predictive ability, and other clinical markers of tumour volume such as palpable disease and numbers of positive cores become more predictive.

Prostate kallikrein markers in diagnosis, risk stratification and prognosis

The kallikrein, prostate-specific antigen (PSA), is one of the world's most frequently used disease biomarkers. After almost two decades of research and clinical experience, the diagnostic and monitoring limitations of PSA are beginning to be understood. Most physicians are aware of PSA's low specificity for cancer among older men with benign prostatic conditions; fewer are aware of recent data, which show that a prior negative biopsy or a prior PSA value below the threshold for biopsy might compromise the predictive accuracy of PSA even further. Furthermore, a subtle increase in serum PSA level during early middle age is strongly correlated with clinically important prostate cancer. We review current and past reports on the prostate kallikreins PSA and hK2 in relation to pathology and epidemiology.

Between-subject variations of transition zone epithelial volume and serum PSA levels in men with benign prostatic hyperplasia

PURPOSE

We verified if the measure of transition zone epithelial volume (TZepiV) could be a valid predictor of serum PSA value in men with benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

Between January 2005 and July 2008, a total of 90 patients undergoing transvesical suprapubic adenomectomy for sintomatic BPH were enrolled. In case of an elevated PSA level (above 4 ng/ml) or abnormal digital rectal examination, systematic multisite biopsies were performed preoperatively to rule out prostate cancer. We have examined PSA levels before and after open surgery, TZ weight as measured by the pathologist and TZepiV by multiplying percentage of epithelium of a single biopsy core with the weight of adenoma. Means, Spearman correlation coefficients and percent change were calculated for all variables and intervals.

RESULTS

The mean serum PSA decreased from 4.8 ng/ml preoperatively to 0.5 ng/ml postoperatively. The mean decrease in PSA was 90% (range 70-99%).The mean weight of enucleated adenoma was 67 gr.(range 18-201) and the TZepiV was 7.7 ml (0.3-28.4). Overall, both TZ volume and TZepiV were correlated to PSA value with TZepiV representing the most predictive variable for PSA (r = 0.54 P = 0.002 vs. r = 0.26 P = 0.02). When we analyzed different ranges of PSA values, only TZepiV was always significantly proportional to PSA.

CONCLUSIONS

Ninety percentage of serum PSA level comes from TZ in range of 0.01-0.17 ng/ml/gr. In presence of equal BPH volumes, the amount of epithelium can be different and it is the main determinant in PSA increase. Thus, TZ epithelial volume could represent a new useful clinical tool able to increase the specificity of PSA in the diagnosis of prostate cancer.

Advantages of prostate-specific antigen (PSA) clearance model over simple PSA half-life computation to describe PSA decrease after prostate adenomectomy

OBJECTIVES

A population kinetic approach based on PSA clearance (CL(PSA)) may be a more rational strategy to characterize prostate-specific antigen (PSA) decrease profile after prostate surgery than the commonly used method (half-life from mono/bi-exponential models).

METHODS

We used 182 post-adenomectomy PSA concentrations from 56 benign prostatic hyperplasia patients to build, with NONMEM software, a multi-exponential and a CL(PSA) model for comparison.

RESULTS

The best multi-exponential model was PSA(t)=4.96e(-)(0.269t)+3.10e(-)(0.16t)+0.746e(+)(0.0002t) with a stable median residual PSA at 0.64 ng/mL. The best model parametrized with clearance was CL(PSA)=0.0229()(AGE/69)(3.78). Akaike information criteria and standard errors favored the CL(PSA) model. Median peripheral zone and transitional zone productions were 0.034 ng/mL/cm(3) and 0.136 ng/mL/g. A threshold at 2 ng/mL on day 90 allowed for a diagnostic of biochemical relapse diagnostic.

CONCLUSIONS

The population CL(PSA) model was superior to the multi-exponential approach for investigating individual post-adenomectomy PSA decreases.

Serum prostate-specific antigen as a predictor of prostate volume in Korean men with lower urinary tract symptoms

The aim of the study was to assess the utility of prostate-specific antigen (PSA) as a predictor of prostate volume indexes (total prostate volume (TPV), transition zone volume and transition zone index) in Korean men with lower urinary tract symptoms (LUTS). From September 2003 to April 2006, 3431 patients with LUTS were included in the study; they had a median age of 63.8 years, a median prostate volume of 22.6 ml and a median serum PSA of 1.04 ng/ml. Men with a baseline PSA of >10 ng/ml were excluded, to reduce the likelihood of including occult prostate cancer. Prostate volume indexes and serum PSA levels had an age-dependent log-linear relationship. Receiver operating characteristic curve analysis showed that PSA had good predictive value for various prostate volume indexes thresholds. The approximate age-specific criteria for detecting men with a TPV of >40 ml are PSA levels of 1.20, 1.44 and 1.72 ng/ml for men with LUTS in their sixth, seventh and eighth decades, respectively. The results show that serum PSA identifies Korean men with large prostates reasonably well. Korean men may produce and/or release more PSA per unit prostate volume than white men. The cutoffs for PSA and prostate volume to response to LUTS therapy should be determined in this population.

Influence of asymptomatic histologic prostatitis on serum prostate-specific antigen: a prospective study

OBJECTIVES

To determine the influence of asymptomatic inflammatory processes of the prostate on serum prostate-specific antigen (PSA) levels.

METHODS

A total of 51 patients with no evidence of prostate cancer or clinical prostatitis were prospectively studied. All subjects underwent 10 to 12 sector transrectal-ultrasound guided needle biopsies of the prostate. Serum PSA was measured 10 minutes before the biopsies. The fragments were stained and histologically analyzed. Two different classifications were used. One divided patients according to the number of specimens with inflammatory processes: 20% or less (group 1), more than 20% to 50% or less (group 2), and greater than 50% (group 3). Any kind of inflammatory process was considered positive. The second was the presence or absence of foreign body-type giant cells. Pearson's nonparametric test was used in the statistical analysis, with P <0.05 considered statistically significant.

RESULTS

The number of specimens with an inflammatory process was statistically significant (P = 0.02), with a median PSA level of 4.96 ng/mL in group 1 patients, 7.40 ng/mL in group 2, and 8.03 ng/mL in group 3 patients. The presence of foreign body-type giant cells in the histologic analysis was not statistically significant, with a median PSA level of 10.21 ng/mL compared with 5.89 ng/mL in the group without these cells.

CONCLUSIONS

The extension of the inflammatory process, as evaluated by the number of specimens involved, was directly related to elevations of serum PSA levels in asymptomatic patients. We could not find a statistically significant relationship between the presence of foreign body-type giant cells and serum PSA levels.

Prostate cancer screening

Prostate cancer is the leading noncutaneous cancer in men of the Western world. Because of its prevalence and ability to cause morbidity and mortality,prostate cancer screening continues to be an important area of focus in health care. This article covers the sensitivity and specificity of prostate-specific antigen and current techniques used to improve the test's validity, the importance of detecting clinically important cancers with screening, as well as the downward stage migration, decreased disease-specific mortality, and decreased metastases rate seen inpatients screened and treated for prostate cancer.

PROSTATE SPECIFIC ANTIGEN ADJUSTED FOR TRANSITION ZONE EPITHELIAL VOLUME: THE POWERFUL PREDICTOR FOR THE DETECTION OF PROSTATE CANCER ON REPEAT BIOPSY

PURPOSE

The indications for repeat prostate biopsy for persistently increased prostate specific antigen (PSA) in men with prostate cancer never detected on previous biopsy are not clear. In this study we determined that PSA adjusted for transition zone (TZ) epithelial volume is the most powerful predictor for detecting prostate cancer on repeat biopsy.

MATERIALS AND METHODS

Repeat prostate biopsies including additional TZ cores were performed in 75 men with PSA between 4.0 and 10.0 ng/ml. TZ epithelial volume was calculated by multiplying TZ volume by the percent of epithelium, which was measured by morphometric analysis using image analysis computer software.

RESULTS

Prostate cancer was detected on repeat biopsy in 19 of the 75 patients. Patients with prostate cancer had a significant smaller percent area of epithelium or glandular lumen than those without cancer. In patients without prostate cancer TZ epithelial volume significantly correlated with total PSA. According to ROC analysis PSA adjusted for TZ epithelial volume had the greatest AUC for cancer detection (0.879). This parameter was able to avoid more than 90% of unnecessary repeat biopsies with 90% sensitivity. Multiple logistic regression analysis showed that PSA complex adjusted for TZ epithelial volume was the significant independent predictor of cancer.

CONCLUSIONS

PSA adjusted for TZ epithelial volume is the most powerful predictor of cancer in men who have undergone previous negative prostate biopsies and in whom PSA remains between 4.0 and 10.0 ng/ml.

Evaluación del antígeno especifico prostático (PSA) ajustado al volumen de la zona transicional en la detección del cáncer de próstata

OBJECTIVE

To 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 METHODS

Data 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.

RESULTS

Of 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.

CONCLUSIONS

PSA-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.

Screening for prostate cancer: current recommendations

Recent studies have questioned the efficacy of PSA as a marker for the early detection of prostate cancer, but techniques are being investigated to improve the sensitivity and specificity of screening. It is hoped that new methods can differentiate between lethal and nonlethal cancers, thereby avoiding lead-time bias. Even with the current limitations of PSA, the combination of stage migration seen with screening, the recent Scandinavian study showing decrease of disease progression following surgical extirpation, and the known mortality in patients presenting with advanced disease help support PSA screening for prostate cancer. It is hoped that prospective, randomized, long-term screening studies, such as the PLCO and ERSCP trials, will show improved survival using the admittedly imperfect PSA marker in prostate cancer screening.

Screening for Prostate Cancer

Prostate cancer is a highly prevalent disease in the Western world. In the United States alone, prostate cancer affects approximately 230,000 men and causes the death of 30,000 American men annually. Several theoretical health care measures may be implemented to decrease the morbidity and mortality of any disease. These measures include prevention, screening, improved curative treatment, and the transformation of an acute lethal disease to a chronic, tolerable one. This summary focuses on the screening aspects of prostate cancer.

Comparison of prostate-specific antigen adjusted for transition zone volume versus prostate-specific antigen density in predicting prostate cancer by transrectal ultrasonography

OBJECTIVE

Prostate-specific antigen is an excellent tumor marker, but it is not specific for prostate cancer. We evaluated the efficacy of prostate-specific antigen adjusted for transition zone volume calculated by transrectal ultrasonography in predicting prostate cancer in men with intermediate prostate-specific antigen levels of 4.1 to 10.0 ng/mL compared with prostate-specific antigen density.

METHODS

Between June 1998 and December 2001, prostate-specific antigen adjusted for transition zone volume was obtained from 131 patients who underwent ultrasonographically guided biopsies and had prostate-specific antigen of 4.1 to 10.0 ng/mL. Prostate-specific antigen density was calculated by dividing total serum prostate-specific antigen by total prostate volume, and total serum prostate-specific antigen was divided by transition zone volume to yield prostate-specific antigen adjusted for transition zone volume. This was compared with prostate-specific antigen density via receiver operating characteristic curves.

RESULTS

Of 131 patients, 34 (26%) had prostate cancer, and 97 (74%) had benign prostatic hyperplasia on pathologic examination. Total prostate volume was correlated with transition zone volume (P < .001). Mean prostate-specific antigen adjusted for transition zone volume and prostate-specific antigen density were 0.71 +/- 0.25 and 0.27 +/- 0.09 ng x mL(-1) x mL(-1) in patients with prostate cancer and 0.32 +/- 0.09 and 0.16 +/- 0.05 ng x ml(-1) x mL(-1) in patients with benign prostatic hyperplasia. With a cutoff value of 0.35 ng mL(-1) x mL(-1), prostate-specific antigen adjusted for transition zone volume had sensitivity of 82% and specificity of 84%. Receiver operating characteristic curve analysis showed that prostate-specific antigen adjusted for transition zone volume predicted biopsy outcome significantly better than prostate-specific antigen density (P < .05).

CONCLUSIONS

Prostate-specific antigen adjusted for transition zone volume is more accurate than prostate-specific antigen density in distinguishing prostate cancer from benign prostatic hyperplasia in men with intermediate serum prostate-specific antigen of 4.1 to 10.0 ng/mL. Determination of transition zone volume by transrectal ultrasonography may be helpful for predicting the probability of positive biopsy results.

Detection of prostate cancer and changes in prostate-specific antigen (PSA) six months after surgery for benign prostatic hyperplasia in patients with elevated PSA

OBJECTIVE

To evaluate early postoperative results of patients with elevated prostate-specific antigen (PSA) levels who underwent surgery due to benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

64 patients who had lower urinary tract symptoms (LUTS), normal digital rectal examinations (DRE), elevated PSA levels and prostate biopsies reported as being benign pathologically in specimens obtained by transrectal ultrasound (TRUS)-guided biopsies, were included in the study. Patients were assessed in accordance with PSA density, free/total PSA ratio and uroflowmetric studies. Patients had no cancer pre- and postoperatively (according to operative specimens). Six months postoperatively, 32 patients were accepted for re-evaluation for all PSA parameters, routine tests and prostatic biopsies.

RESULTS

64 patients with a mean age of 66.8 (SD 6.72) were included in the study. Total PSA average value was 14.38 (SD 7.49) ng/ml. Free PSA average value was 2.11 (SD 1.43) ng/ml. Average PSA density and free/total PSA ratio were 25.19 SD (14.12) ng/ml/cm(3) and 14.53% (SD 5.35%) respectively. 56 patients had BPH, 7 had chronic prostatitis and 1 had prostatic intraepithelial neoplasia (PIN) preoperatively with biopsies. Re-biopsy of the patient with PIN was reported as BPH. In pathologic examination with resected tissues postoperatively, 49 patients had BPH, 14 had chronic prostatitis and 1 had PIN. In the sixth month, average values of free/total PSA were 0.45 (SD 0.26) and 3.71 (SD 4.96) ng/ml respectively. Average PSA density and free/total PSA ratio were 12.41 (SD 13.8) ng/ml/cm(3) and 19.59% (SD 10.33%) respectively. There were significant decreases in PSA densities (p < 0.001) and increases in free/total PSA ratios (p = 0.004). Seven patients still had elevated PSA levels 6 months postoperatively. Three of 7 patients were reported as chronic prostatitis. One of them was indicated as prostatic carcinoma who was reported as PIN preoperatively. All other patients were stated as BPH at re-biopsies.

CONCLUSION

If pretreatment biopsies are negative and operative specimens are also benign in patients with high PSA values, these patients can be followed up like usual BPH patients, but long-term follow-up is still unclear.

Prostate-specific antigen levels and density in the internal and external glands of the prostate in benign prostatic hyperplasia patients with normal or gray-zone PSA levels

OBJECTIVE

In patients with benign prostatic hyperplasia (BPH) showing normal prostate-specific antigen (PSA) levels (normal PSA group) and those with BPH showing gray-zone PSA levels (gray-zone PSA group), we assessed PSA levels secreted from the internal and external glands.

MATERIALS AND METHODS

We performed transurethral enucleation of the prostate (TUE) in 102 BPH patients with normal PSA and 59 BPH patients with gray-zone PSA at our department from 1999 to 2001. Preoperatively and approximately 6 months postoperatively, we measured serum PSA levels and determined prostatic volumes via transrectal ultrasonography (TRUS) to calculate PSA levels secreted from the internal and external glands as well as various PSA density (PSAD) values.

RESULTS

The total PSA level was 1.8 and 6.1 ng/ml in the normal and gray-zone PSA groups, respectively. The PSA level of the external gland was 0.6 and 0.8 ng/ml and the PSAD of the external gland was 0.07 and 0.08 ng/ml/cm(3) in the normal and gray-zone PSA groups, respectively. The internal gland PSA was 1.3 and 5.4 ng/ml and the internal gland PSAD value was 0.11 and 0.30 ng/ml/cm(3) in the normal and gray-zone PSA groups, respectively.

CONCLUSIONS

Our results demonstrated that increased PSA levels in BPH cases with gray-zone PSA were attributable to increased PSA secreted from the internal gland rather than from the external gland. In our opinion, the determination of PSA and PSAD of the internal and external gland may be clinically significant in the future.

Relationship between Prostatic Specific Antigen (PSA) and volume of the prostate in the Benign Prostatic Hyperplasia in the elderly

Increase of the Prostatic Specific Antigen (PSA) is a non-invasive, sensitive and specific markers for prostatic diseases, including prostatic cancer. However, age-related Benign Prostatic Hyperplasia (BPH), as well as prostatitis, may at the same time alter PSA values. The aim of this study was to evaluate the relationship between ageing and PSA, and whether age-specific upper normal limits of PSA should be considered for elderly patients. We evaluated 569 consecutive subjects aged 60 years or more (mean age 74.2 years) who were free from malignant prostatic disease, without clinical evidence of prostatic phlogosis and who were not receiving PSA levels affecting drugs. All patients underwent Digital Rectal Examination (DRE) and Trans-Rectal Ultrasonography (TRU), with determination of the three prostatic diameters, the Maximum Adenoma Diameter (MAD) and calculation of the prostatic volume (PV) by the ellipsoid formula. PSA was determined in all patients before DRE and TRU, and the PSA free ratio was determined in those with total PSA values >4 ng/ml. The PSA density was calculated according to the formula PSA/PV. One hundred and seventy-nine subjects (31.6%) were found to have PSA values >4 ng/ml: among them, 26 (14.5%) had values exceeding 10 ng/ml. Age was slightly correlated with PV (P<0.05), but not with PSA values. On the contrary, PSA values were strongly related with PV and MAD (P<0.01 both). Mean PSA-free ratio was 16.3+/-6.0% and most of patients had values in the so-called 'grey zone' of discrimination between benignity and malignity. Elevated PSA levels are common in older subjects without evidence of prostatic malignancy; PSA values are poorly affected by age itself and strongly correlated with increasing PV. These results suggest the possibility to consider as indicative of benignity PSA values between 4 and 10 ng/ml, when these values are associated with relevant increase of PV and with PSA-free ratio greater than 10%.

[Value of prostate-specific antigen density and transitional-zone prostate-specific antigen density in the diagnosis of prostate cancer]

INTRODUCTION

With serum prostate specific antigen (PSA) levels of 4.1 to 10 ng/ml a significant number of patients are unnecessary subjected to biopsy. We try to determine if the calculation of prostate specific antigen density (PSAD) and prostate specific antigen density of the transition zone (PSADTZ) improve the capacity to discriminate between non-malignant disease and prostate cancer.

METHODS

A prospective study including 314 males with PSA levels between 4.1 and 10 ng/ml is reported. Transrectal ultrasonography and prostatic biopsy were performed in all of them and total prostate and transition-zone volumes were calculated. PSA density and PSA density of the transition zone were calculated for each patient. Receiver operating characteristics (ROC) curves for PSA, PSAD and PSADTZ were constructed for all the patients and for those patients with digital rectal examination unsuspicous of malignancy, determining the sensitivity and specificity for several cutoff values.

RESULTS

The area under the curve for both, PSAD and PSADTZ, were greater than for PSA (p < 0.05), without any significant differences between PSADTZ and PSAD. The cutoff value of greatest diagnostic efficiency for PSAD was 0.17 ng/ml/cc (71.4% sensitivity and 55.7% specificity), while it was 0.41 ng/ml/cc for DPSATZ (70% sensitivity and 61.5% specificity). For those cases of normal digital rectal examination, no differences were observed between PSA and PSAD but they were between PSA and PSADTZ. In any event, the area under ROC curves was always less than 0.7, and, in order to avoid a large number of biopsies (high specificity), a large number of cancers are left without diagnosis (low sensitivity).

CONCLUSIONS

We conclude that PSAD and PSADTZ are not excessively useful for adequately discriminating between patients with prostate cancer and those with non-malignant disease, particularly when digital rectal examination is normal.

Relationship between serum prostate-specific antigen and calculated epithelial volume

OBJECTIVES

To estimate the relationship between serum prostate-specific antigen (PSA) and prostatic epithelial volume, a new simple method for measuring epithelial volume was developed and its efficacy evaluated in patients with benign prostatic hyperplasia.

METHODS

Between March 1998 and June 2001, 122 patients without prostate cancer in the transurethral resected specimen were enrolled in this study. Of the 122 patients, 55 had a serum PSA level of 4.0 ng/mL or greater and negative sextant biopsies before surgery. First, we measured the epithelium/glandular lumen ratio by computer image analysis in 20 specimens. Second, we measured the percentage of glandular lumen in all 122 patients. The prostatic epithelial volume was then calculated as follows: calculated epithelium volume (in cubic centimeters) = epithelium/glandular lumen ratio percentage of glandularlumen x total prostate volume (in cubic centimeters).

RESULTS

The epithelium/glandular lumen ratio was 1.01 in the 20 specimens. In the 122 patients with benign prostatic hyperplasia, the calculated epithelial volume correlated more strongly with the serum PSA level than did the total prostate volume, transition zone volume, or percentage of epithelium (gamma = 0.672, P <0.0001). The mean PSA level per calculated epithelial volume was 1.27 ng/mL/cm(3). The calculated epithelial volumes from the biopsy specimens correlated significantly with those from transurethral resection specimens (gamma = 0.956, P <0.0001).

CONCLUSIONS

Serum PSA levels correlated significantly with prostatic epithelial volumes in patients with benign prostatic hyperplasia. The method of measuring prostatic epithelial volume used in this study is very convenient for clinical practice.

Prostate-specific antigen, prostate volume and transition zone volume in Japanese patients with histologically proven benign prostatic hyperplasia

The relationship among age, prostate-specific antigen (PSA) level and prostate volume in Japanese patients with lower urinary tract symptoms (LUTS) and histologically proven benign prostatic hyperplasia (BPH) was examined in order to assess the utility of PSA as a predictor of prostate volume. Two hundred eighteen patients with LUTS were confirmed to have BPH by histological examination for the reason of elevated PSA and/or abnormal digital rectal examination finding. Correlation among PSA, prostate volume and transition zone volume were analyzed in patients classified into age-stratified groups. Prostate volume increased with age. Mean serum PSA increased with age, and the correlation of PSA and prostate volume was determined to be statistically significant in each cohort of age. A correlation coefficient ranged from 0.315 to 0.439. In patients with LUTS and clinical BPH, serum PSA increased with age and was related to prostate volume. PSA might be useful for therapeutic decision making for patients with symptomatic BPH.

The value of power Doppler imaging to predict the histologic components of benign prostatic hyperplasia

BACKGROUND

The response of symptoms caused by benign prostate hypertrophy (BPH) to alpha blockade is related to the area density of the smooth muscle of the prostate. If this density could be determined by ultrasound examination, ultrasound might be useful in predicting the efficacy of alpha-blocker therapy. In this study, various ultrasonographic parameters obtained by transrectal method (TRUS) were compared with histologically measured components.

METHODS

Before surgery, ultrasonic power Doppler imaging (PDI) of the prostate was performed using a transrectal probe. The volume of total prostate, transition zone (TZ), and the presumed circle area ratio (PCAR) [1,2] were calculated. Pulsatile blood flow was recorded, and the resistive index (RI) was calculated. Based on the serum concentration of total prostate specific antigen (PSA), ratio of PSA to prostate volume (PSAD), and ratio of PSA to TZ (PSAT) were calculated. Prostate tissues were obtained from 26 patients undergoing transurethral resection, suprapubic prostatectomy, or radical cystectomy, and were analyzed by quantitative morphometry. Computer image analysis was used to determine the mean area densities of the smooth muscle (SM), connective tissue (CT), glandular epithelium (GE) and lumen (GL), and vascular lumen (V). Correlations between ultrasonographic parameters and morphometric data were studied.

RESULTS

On microscopic examination, the specimens showed a wide variety, ranging from normal prostate to typical glandular hyperplasia. There was a correlation between RI and the ratios of the four components (SM: r = -0.42 P = 0.034; CT: r = -0.42 P = 0.030; GE: r = 0.42 P = 0.032; GL: r = 0.46 P = 0.018). However, correlations between the other five transrectal parameters and the composition of the prostate were not so clear. This may have been because the blood vessels are compressed within the surgical capsule together with the urethra.

CONCLUSIONS

The present study demonstrates that when RI is calculated by PDI, it can be quite useful for predicting component ratios, thereby making it possible to predict the therapeutic efficacy of alpha-blockers in individual patients.

Transitional zone and anterior peripheral zone of the prostate. A correlation of small-volume cancer in the biopsy cores and high psa with positive anterior margins in radical prostatectomy specimens

INTRODUCTION

Prognostically significant prostatic adenocarcinomas (PAC) may pose diagnostic problems if they were localized in the anterior peripheral zone (APZ) or transitional zone (TZ).

MATERIALS AND METHODS

108 cases of PAC were reviewed along with serum PSA and TRUS biopsies. The PACs were divided into 22 TZ, 17 APZ and 69 posterior peripheral zone (PPZ) PACs according to the location of the main tumor mass in the TZ and anterior or posterior half of the peripheral zone in the radical prostatectomy (RP) specimens.

RESULTS

In comparison with PPZ PAC, TZ PAC had a higher cancer volume in RP specimens (4 +/- 2.1 vs. 2.5 +/- 1.7 cm3, p < 0.01), a higher serum PSA (16.5 +/- 9.8 vs. 8.4 +/- 4.5 microg/l, p < 0.001), a biopsy with a small cancer volume (3.8 +/- 2.1 vs. 11.8 +/- 9.4 mm, p < 0.005), and a lower Gleason's score (4.8 +/- 2.1 vs. 6.5 +/- 1.7). APZ PAC was characterized by the cancer volume in RP and biopsy and PSA intermediate between those of TZ and PPZ PAC. Among 24 PACs with a total cancer core length of <3 mm, 19 cases were from the TZ and APZ groups and also had a higher cancer volume and PSA than those from the PPZ group (2.9 +/- 1.8 vs. 1.5 +/- 1.3 and 13.7 +/- 8.3 vs. 9.6 +/- 4 microg/l, respectively). Furthermore, there was a better correlation coefficient (r(2)) of tumor volume in the biopsy and RP for PPZ than for all zones PAC (r2 = 0.75 vs. 0.29). TZ and APZ carcinomas were associated with extension or satellite nodules of PAC in the PPZ that may be diagnosed with biopsies. These PACs were associated with positive anterior resection margin due to extracapsular extension of the carcinoma or intracapsular dissection in 6 and 5 cases respectively.

CONCLUSIONS

TZ and APZ PACs accounted for the poor correlation between the tumor volume in the biopsy and the RP, and were associated with positive anterior resection margins. One core biopsy with a total cancer core length of <3 mm and PSA >10 microg/l are suspicious for TZ and APZ PCA in patients with undetectable tumors with DRE or TRUS. Clinically insignificant PACs tend to be associated with cancer core <3 mm and PSA <10 microg/l.

The influence of prostate volume on the prostate-specific antigen (PSA) level adjusted for the transition zone volume and free-to-total PSA ratio: a prospective study

OBJECTIVES

To evaluate the influence of prostate volume on the prostate-specific antigen (PSA) level adjusted for the transition zone volume (PSAT) and free-to-total PSA ratio (f/tPSA) in detecting prostate cancer in men with intermediate PSA levels of 4.1-10.0 ng/mL.

PATIENTS AND METHODS

From March 1997 to June 1999, the f/tPSA and PSAT were measured in 105 patients who underwent ultrasound-guided systemic biopsies and had a PSA level of 4.1-10.0 ng/mL, with an apparently normal prostate on a digital rectal examination. The PSAT and f/tPSA were evaluated in all patients and in subgroups of patients with small (< 40 mL) or large (> or = 40 mL) prostates, using receiver operating characteristic (ROC) curves.

RESULTS

Total prostate volume was highly correlated with transition zone volume in all patients and in both subgroups (P < 0.001). In all 105 patients, PSAT had a sensitivity of 82% and its use would have avoided the largest number of unnecessary biopsies (87% specificity) at a threshold value of 0.35 ng. In men with small prostates f/tPSA and PSAT had a high sensitivity and specificity, at threshold values of 0.12 and 0.35 ng, respectively. In large prostates the PSAT was superior to f/tPSA in detecting prostate cancer.

CONCLUSIONS

These results suggest that both f/tPSA and PSAT are useful in detecting prostate cancer in men with small prostates, while PSAT is superior to f/tPSA in detecting prostate cancer in men with large prostates.

Prostate specific antigen adjusted for transition zone volume: the most powerful method for detecting prostate carcinoma

BACKGROUND

Several methods for the identification of patients with prostate carcinoma have been proposed to enhance the clinical usefulness of prostate specific antigen (PSA). However, it remains unclear which method is superior in practical use. The authors attempted prospectively to identify the most powerful method with which to detect prostate carcinoma, especially among patients with intermediate PSA levels.

METHODS

Between October 1997 and August 1999, systematic sextant biopsies were performed on 281 patients, including 147 with PSA levels between 4.1 ng/mL and 10.0 ng/mL. The clinical values of PSA, the free PSA to total PSA ratio (free/total PSA ratio), alpha-1-antichymotrypsin-PSA complex (PSA-ACT), the calculated derivatives, PSA density (PSAD), and PSA density of the transition zone (PSATZD) for the detection of prostate carcinoma were compared by using receiver operating characteristic (ROC) curves and logistic regression analyses.

RESULTS

According to ROC curve analysis, PSATZD had the greatest area under the curve in the overall patient population and in patients with intermediate PSA levels. In patients with intermediate PSA levels, at the sensitivity of 90%, PSATZD would have prevented unnecessary biopsies in 68 of 117 patients who were without prostate carcinoma, whereas PSA, free/total PSA ratio, and PSA-ACT would have prevented unnecessary biopsies in 25, 28, and 25 patients, respectively. Stepwise logistic regression analysis showed that PSATZD and findings on digital rectal examination were significant independent predictors.

CONCLUSIONS

PSATZD had the most useful validity in the differentiation between prostate carcinoma and benign prostatic enlargement in the overall patient population and in patients with intermediate PSA levels.

Can prostate epithelial content predict response to hormonal treatment of patients with benign prostatic hyperplasia?

OBJECTIVES

There are large interindividual differences in response to medical therapy for men with benign prostatic hyperplasia. Selection of patients for alpha-blocker versus hormonal treatment is often based more on assumptions than on well-documented knowledge. A more scientifically based decision of therapy has a potential for economical savings and increased effectiveness.

METHODS

We performed morphometry on prostate biopsy specimens and determined the amount of stroma, epithelium, and glandular lumen (pretreatment characteristics) in 34 men with benign prostatic hyperplasia before 24 weeks of androgen suppressive therapy. Androgen suppressive therapy consisted of either the luteinizing hormone-releasing hormone agonist leuprolide depot (3.75 mg intramuscularly every 28 days) or the nonsteroidal antiandrogen bicalutamide (50 mg/day orally). The evaluation of the clinical response (effectiveness parameters) was based on changes in prostate volume, peak urinary flow rate, symptom score, and bladder outlet obstruction.

RESULTS

A large prostate volume before treatment was associated with more pronounced symptom score improvement, but neither prostate-specific antigen nor any of the parameters of tissue composition used (percentage of epithelium, epithelial volume, and stromal/epithelial ratio) predicted a favorable response to hormonal treatment.

CONCLUSIONS

The pretreatment variables that are readily available at present have a limited role in helping clinicians to decide the optimal medical treatment for patients with benign prostatic hyperplasia.

Effect of prostatic biopsy on free-to-total prostate-specific antigen ratio in patients with prostate cancer

BACKGROUND

We determined the effect of prostatic biopsy on the changes in total and free prostate-specific antigen (PSA) and free-to-total PSA ratio (F/T ratio) and examined if there are differences in these parameters between patients with benign and malignant histologic findings.

METHODS

The concentration of total and free PSA and the F/T ratio were determined in 35 men before and 1 h after prostatic biopsy. The level of PSA was measured with a chemiluminescent enzyme assay. Of 35 patients, nine were diagnosed as having prostate cancer.

RESULTS

In patients whose biopsy revealed cancer, the F/T ratio was lower than those without cancer, although there were no differences in total and free PSA value before prostatic biopsy. One hour after prostatic biopsy, there was an increase in the level of total and free PSA and the F/T ratio in all men. The increase in the F/T ratio was greater in patients whose biopsies revealed no prostate cancer. In patients with stage B cancer, these parameters increased more than those with stage C/D cancer.

CONCLUSION

Prostatic biopsy causes a dramatic increase in total and free PSA. The F/T ratio also increased after biopsy. The PSA response to prostatic biopsy might be different in patients with and without prostatic malignancy. The response might also be different according to stage of prostate cancer.

Pretreatment prostate-specific antigen as an outcome predictor of targeted transurethral microwave thermotherapy

OBJECTIVES

To evaluate pretreatment serum prostate-specific antigen (PSA) as an outcome predictor of targeted microwave thermotherapy.

METHODS

Seventy-one patients with lower urinary tract symptoms of benign prostatic hyperplasia underwent targeted transurethral microwave thermotherapy using the Targis system. Outcomes 12 months after treatment were evaluated by the International Prostate Symptom Score (IPSS), peak urinary flow rate (Qmax), and quality-of-life (QOL) score. The ability of PSA to predict outcomes was evaluated by linear and logistic regression and receiver operating characteristic curve analysis.

RESULTS

Higher pretreatment PSA levels were significantly predictive of an absolute IPSS change of -7.5 or less for patients with moderate baseline symptoms or - 15 or less for those with severe baseline symptoms; an absolute Qmax change of 5 mL/s or greater; an absolute QOL score change of -3 or less; an IPSS at 12 months of 7 or less; a Qmax at 12 months of greater than 12 mL/s; and a QOL score at 12 months of 1 or less. Nevertheless, even without taking pretreatment PSA into account, most patients benefitted substantially from targeted microwave thermotherapy. Thus, 74%, 71%, and 79% of all eligible patients improved 50% or more in IPSS, Qmax, and QOL score, respectively, at 12 months compared with baseline. No significant association between PSA and either prostate or transition zone volume could be demonstrated.

CONCLUSIONS

Most patients benefit substantially from targeted microwave thermotherapy. However, higher PSA levels are significantly predictive of more favorable outcomes. This association may reflect patient-to-patient differences in the relative abundance of PSA-producing epithelial cells in the transition zone of the prostate.

Prostate-specific antigen adjusted for the transition zone volume versus free-to-total prostate-specific antigen ratio in predicting prostate cancer

BACKGROUND

We performed this study to assess the efficacy of prostate-specific antigen adjusted for the transition zone volume (PSATZ) and free-to-total prostate-specific antigen (PSA) ratio (F/T ratio) in predicting prostate cancer in men with intermediate PSA levels of 4.1-10.0 ng/mL.

METHODS

Between March 1997 and September 1998, PSATZ was obtained from 67 patients who underwent ultrasonography guided systemic sextant biopsies and had a PSA of 4.1-10.0 ng/mL. PSATZ was compared with F/T ratio via receiver operating characteristic (ROC) curves.

RESULTS

Of 67 patients, 22 (32.8%) had prostate cancer and 45 (67.2%) had benign prostatic hyperplasia (BPH) on pathologic examination. Mean PSA, PSA density, F/T ratio and PSATZ were 7.96+/-2.01ng/mL, 0.28+/-0.14 ng/mL/cc, 0.10+/-0.06 and 0.70+/-0.28 ng/mL/cc in patients with prostate cancer and 6.39+/-1.68 ng/mL, 0.16+/-0.06 ng/mL/cc, 0.15+/-0.05 and 0.29+/-0.10 ng/mL/cc in patients with BPH, respectively. The ROC curve analysis demonstrated that PSATZ predicted the biopsy outcome significantly better than F/T ratio in all 67 patients (P<0.01) and in a subset of 53 men with normal digital rectal examination (P<0.01). With a cut-off value of 0.35 ng/mL/cc, PSATZ had a sensitivity of 86% and a specificity of 89% for predicting prostate cancer.

CONCLUSIONS

These results suggest that PSATZ and F/T ratio may be useful in diagnosing prostate cancer with intermediate levels of PSA. Prostate-specific antigen adjusted for the transition zone volume is more accurate than F/T ratio in distinguishing benign prostatic disease from prostate cancer. But large prospective studies are required to assess the precise role of PSATZ and F/T ratio in early prostate cancer detection.

Two-dimensional electrophoresis of prostate-specific antigen in sera of men with prostate cancer or benign prostate hyperplasia

Prostate-specific antigen (PSA), the main marker for prostate cancer (PCa), is released from the prostate into the blood stream at nanogram level and may increase in PCa and nonmalignant disease such as benign prostate hyperplasia (BPH). More recently, advantage was taken of PSA's ability to bind to protease inhibitors in serum in order to improve discrimination between PCa and BPH, using the free PSA to total PSA ratio. The understanding of this phenomenon at molecular level, which is still unknown, may promise new improvements in the field of diagnostics. For this purpose, we determined the pattern of PSA forms in PCa and BPH sera, using the high resolving power of two-dimensional electrophoresis (2-DE) in conjunction with the high sensitivity of chemiluminescence detection. Serum PSA differs drastically from seminal PSA: apart from complexed forms, serum PSA shows few cleaved forms. Moreover, 2-DE patterns from PCa are relatively homogeneous, whereas patterns from BPH may in some cases present a higher proportion of cleaved forms and in other cases present slightly more basic spots. We therefore demonstrated, for the first time, that an increase in the free to total PSA ratio in BPH cases may be due to cleaved PSA forms (which are enzymatically inactive and unable to bind inhibitors), or possibly related to basic free PSA, which may represent the zymogen forms.

Advantages of replacing the total PSA assay with the assay for PSA-alpha 1-antichymotrypsin complex for the screening and management of prostate cancer

Several advantages become immediately apparent when the prostate specific antigen (PSA, or tPSA) assay is replaced by the assay specific for the serum PSA-alpha 1-antichymotrypsin (PSA-ACT) complex. For instance, random contributions to the tPSA value by various serum minor PSA isoforms can be avoided, making possible the determination of a more accurate relation of the PSA-ACT concentration to the tumor activity. Discrepancies in percent free PSA (% fPSA) values from the same specimens due to the use of different commercial kits also can be eliminated, mainly because the PSA-ACT assay does not have the problems in antibody selection and calibrator preparation usually associated with the tPSA assay. We found that at the present time different cutoffs of % fPSA for the differentiation of BPH from prostate cancer must be established for each individual tPSA assay. Cutoffs established using values from one tPSA assay should not be used for making clinical decisions when their tPSA values are determined by a different kit. Moreover, when we monitored the patients during treatment with serum tPSA, specific fPSA, and specific PSA-ACT complex assays simultaneously, it was clear that any interpretation of the patient's clinical status based on tPSA values alone could be misleading. Because there is less PSA-ACT complex in BPH specimens relative to that found in cancer serum samples, expressing fPSA as "fPSA/PSA-ACT x 100" and measuring PSA-ACT complex concentrations instead of tPSA during screening improve the measurable contrast between BPH and prostate cancer. Although individually modest, collectively these advantages can add up to considerable improvements.