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Total PSA (total + psa)

Distribution by Scientific Domains

Medical Sciences	86%

Selected Abstracts

Changes in molecular forms of prostate-specific antigen during treatment with finasteride

BJU INTERNATIONAL, Issue 7 2002
F. España
Objective ,To study the influence of finasteride treatment on the molecular forms of prostate-specific antigen (PSA) in patients with benign prostatic hyperplasia (BPH). Patients and methods ,Total PSA, free PSA and PSA complexed to ,1 -antichymotrypsin (PSA-,1ACT) were measured in plasma and serum from 40 men with BPH and a total PSA of <,20 ng/mL, using in-house and commercial immunoassays, before and during treatment with finasteride (30 men) or placebo (10 men). Results ,The baseline values were not significantly different between the groups, with mean (sd) total plasma PSA levels of 3.6 (4.3) and 4.8 (5.9) ng/mL in the finasteride and placebo groups, respectively. Finasteride, but not placebo, induced a significant reduction in total PSA, free PSA and PSA-,1ACT levels in plasma and serum (P < 0.001). However, complexed-to-total (c/t) and free-to-total (f/t) PSA ratios remained constant in both groups, both in plasma and serum, during the follow-up. Conclusion ,The decrease in total PSA after finasteride treatment results from a proportional reduction in its two major molecular forms, free PSA and PSA-,1ACT, which explains why the c/t and f/tPSA ratios do not change significantly despite treatment. This suggests that routine analysis of molecular forms of PSA could improve the utility of the change in total PSA associated with finasteride for the early diagnosis of prostate cancer. It also suggests that any subsequent change in both ratios, particularly an increase in c/tPSA or a decrease in f/tPSA ratio, could be considered an early sign of neoplastic degeneration rather than a therapeutic consequence. [source]

An artificial neural network for five different assay systems of prostate-specific antigen in prostate cancer diagnostics

BJU INTERNATIONAL, Issue 7 2008
Carsten Stephan
OBJECTIVE To compare separate prostate-specific antigen (PSA) assay-specific artificial neural networks (ANN) for discrimination between patients with prostate cancer (PCa) and no evidence of malignancy (NEM). PATIENTS AND METHODS In 780 patients (455 with PCa, 325 with NEM) we measured total PSA (tPSA) and free PSA (fPSA) with five different assays: from Abbott (AxSYM), Beckman Coulter (Access), DPC (Immulite 2000), and Roche (Elecsys 2010) and with tPSA and complexed PSA (cPSA) assays from Bayer (ADVIA Centaur). ANN models were developed with five input factors: tPSA, percentage free/total PSA (%fPSA), age, prostate volume and digital rectal examination status for each assay separately to examine two tPSA ranges of 0,10 and 10,27 ng/mL. RESULTS Compared with the median tPSA concentrations (range from 4.9 [Bayer] to 6.11 ng/mL [DPC]) and especially the median %fPSA values (range from 11.2 [DPC] to 17.4%[Abbott], for tPSA 0,10 ng/mL), the areas under the receiver operating characteristic curves (AUC) for all calculated ANN models did not significantly differ from each other. The AUC were: 0.894 (Abbott), 0.89 (Bayer), 0.895 (Beckman), 0.882 (DPC) and 0.892 (Roche). At 95% sensitivity the specificities were without significant differences, whereas the individual absolute ANN outputs differed markedly. CONCLUSIONS Despite only slight differences, PSA assay-specific ANN models should be used to optimize the ANN outcome to reduce the number of unnecessary prostate biopsies. We further developed the ANN named ,ProstataClass' to provide clinicians with an easy to use tool in making their decision about follow-up testing. [source]

Different prostate-specific antigen assays give different results on the same blood sample: an obstacle to recommending uniform limits for prostate biopsies

BJU INTERNATIONAL, Issue 6 2007
Carsten Stephan
OBJECTIVE To show the effect of different results for total prostate specific antigen (tPSA) and percentage free/total PSA (%fPSA) obtained with different assays for differentiating between benign and malignant prostate diseases. PATIENTS AND METHODS Data were used for tPSA and fPSA levels from 596 patients with prostate cancer (314) or no evidence of cancer (282) within the PSA range 0.5,10 ng/mL, analysed with assays from Abbott (AxSYM), Beckman Coulter (Access), DPC (Immulite 2000), and Roche (Elecsys 2010), and with tPSA and complexed PSA (cPSA) assays from Bayer (ADVIA Centaur), as already reported. Receiver operating characteristics (ROC), specificities at assay-dependent and fixed thresholds, and the percentages of correct classification rates of patients were calculated. RESULTS Whereas the areas under the ROC curves were no different among all tPSA assays, the assay-specific thresholds at 90% sensitivity were 2.5,3.1 ng/mL. When using fixed 2.5 or 4 ng/mL tPSA thresholds there was a wide sensitivity range, with significant differences among almost all assays, resulting in significantly different classification rates of patients. These differences were even larger when using fixed %fPSA thresholds. CONCLUSIONS The current situation of differences among PSA values measured with different assays do not allow the recommendation of uniform PSA limits as biopsy criteria. For that purpose, better harmonization of PSA values between the different PSA test systems must be realized. [source]

Discordant performance of assays for free and total prostate-specific antigen in relation to the early detection of prostate cancer

BJU INTERNATIONAL, Issue 6 2001
B.G. Blijenberg
Objective To assess the value of applying rigid threshold values in interpreting prostate specific antigen (PSA) results, by selecting and comparing five current methods for measuring free and total PSA. Materials and methods Samples taken from an ongoing screening study for prostate cancer (total PSA by Tandem-E assay, 17,334 participants; biopsy criterion a PSA of 3.0 µg/L, 4,464 men) from men with a total PSA of 1.0,6.0 µg/L were measured for free and total PSA using the Access, Immulite, Elecsys and Prostatus analysis kits, in two patient groups, i.e. with prostate cancer or no evidence of disease. Results Both patient groups had equal means for total PSA but not for free PSA. In all, 360 samples from men with cancer and 96 from men with no evidence of disease were analysed. All methods applied to both groups deviated statistically significantly from the Tandem-E result for total PSA, except for the Access kit. There was a close correlation among all the methods (correlation coefficients of 0.89,0.97). There were very discordant results for the combination of the Tandem-E vs Prostatus (8% difference), representing 315 participants at a threshold of 3.0 µg/L. For free PSA (free/total PSA) the situation was worse, with extreme differences of 32% and 36% for both patient groups (Elecsys vs Access). Conclusions Depending on the threshold value applied as an indication for biopsy, when using the total PSA alone or combined with the free/total PSA, care is needed in interpreting patient groups because of the discordance among PSA assays. [source]

Evaluation of molecular forms of prostate-specific antigen and human kallikrein 2 in predicting biochemical failure after radical prostatectomy

INTERNATIONAL JOURNAL OF CANCER, Issue 3 2009
Sven Wenske
Abstract Most pretreatment risk-assessment models to predict biochemical recurrence (BCR) after radical prostatectomy (RP) for prostate cancer rely on total prostate-specific antigen (PSA), clinical stage, and biopsy Gleason grade. We investigated whether free PSA (fPSA) and human glandular kallikrein-2 (hK2) would enhance the predictive accuracy of this standard model. Preoperative serum samples and complete clinical data were available for 1,356 patients who underwent RP for localized prostate cancer from 1993 to 2005. A case-control design was used, and conditional logistic regression models were used to evaluate the association between preoperative predictors and BCR after RP. We constructed multivariable models with fPSA and hK2 as additional preoperative predictors to the base model. Predictive accuracy was assessed with the area under the ROC curve (AUC). There were 146 BCR cases; the median follow up for patients without BCR was 3.2 years. Overall, 436 controls were matched to 146 BCR cases. The AUC of the base model was 0.786 in the entire cohort; adding fPSA and hK2 to this model enhanced the AUC to 0.798 (p = 0.053), an effect largely driven by fPSA. In the subgroup of men with total PSA ,10 ng/ml (48% of cases), adding fPSA and hK2 enhanced the AUC of the base model to a similar degree (from 0.720 to 0.726, p = 0.2). fPSA is routinely measured during prostate cancer detection. We suggest that the role of fPSA in aiding preoperative prediction should be investigated in further cohorts. © 2008 Wiley-Liss, Inc. [source]

Value of prostate specific antigen ,1 -antichymotrypsin complex for the detection of prostate cancer in patients with a PSA level of 4.1,10.0ng/mL: Comparison with PSA-related parameters

INTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2001
Hideaki Miyake
Abstract Background: The aim of the present study was to evaluate the usefulness of prostate specific antigen ,1 -antichymotrypsin complex (PSA-ACT) in the differential diagnosis of prostate cancer in patients with a PSA level of 4.1,10.0 ng/mL compared to several PSA- and PSA-ACT-related parameters. Methods: Serum samples were obtained from 103 patients with no evidence of malignancy on biopsy and 29 with histologically confirmed prostate cancer. All patients had pretreatment serum PSA levels between 4.0 and 10.0 ng/mL. The different forms of serum PSA, including total PSA (tPSA), free PSA (fPSA) and PSA-ACT were measured using immunofluorometric techniques with different monoclonal antibodies against PSA and ACT. Furthermore, tPSA and PSA-ACT densities of the whole prostate (PSAD and ACTD, respectively) and the f-to-tPSA and the f-to-PSA-ACT ratios (F/T ratio and F/ACT ratio, respectively) were calculated. Results: The differences between patients with prostate cancer and benign prostatic disease were significant with respect to all six parameters examined in this study. Analysis of receiver operating characteristics revealed that the areas under the curve for PSA-ACT, ACTD and the F/ACT ratio were larger than those for tPSA, PSAD and the F/T ratio, respectively. However, there were no significant differences in discrimination between benign and malignant diseases among these six parameters. Conclusions: In patients who have an intermediate serum PSA level, PSA-ACT and its associated parameters may not be significantly superior in the differential diagnosis between prostate cancer and benign prostatic diseases compared to tPSA and its traditional relatives. [source]

Change in the ratio of free-to-total prostate-specific antigen during progression of advanced prostate cancer

INTERNATIONAL JOURNAL OF UROLOGY, Issue 3 2000
MASASHI TANAKA
Abstract Background: The ratio of free-to-total prostate-specific antigen (PSA) is different in benign prostatic hyperplasia and in the early stage of prostate cancer. The present study was undertaken to examine the ratio of free-to-total PSA in the advanced stage of this cancer and its subsequent change during course of the disease. Methods: Free and total PSA were measured in sera collected from the following patients with benign and cancerous prostatic diseases: 47 cases of benign prostatic hypertrophy, nine in T1C with less than 10 ng/mL of total PSA, 11 in stage C, 16 in D2, 22 in remission under endocrine therapy, and 12 in relapse. In addition, PSA was measured sequentially in four other patients who were also in relapse. Results: The ratio of free-to-total PSA was similar in early and advanced stages of untreated prostate cancer and was lower than that in benign prostatic hyperplasia. The ratio increased to the level of benign prostatic hyperplasia during remission from stages C and D2 under endocrine therapy. There was no correlation with the intervals from the start of the therapy to examination. Following relapse, the ratio came down gradually to the level obtained in untreated prostate cancer. Conclusion: The ratio of free-to-total PSA was similar in all stages of untreated prostate cancer. Response and relapse to endocrine therapy were associated with increase and decrease in ratio, respectively. [source]

Expanding the Criteria of Organ Procurement from Donors with Prostate Cancer: The Application of the New Italian Guidelines

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2010
A. D'Errico-Grigioni
Prostate cancer (CaP) represents the most prevalent malignancy in men more than 60-year-old, posing a problem in organ procurement from elderly subjects. However, most of the currently diagnosed CaP are low-grade and intraprostatic, with low metastatic risk, and there is recent evidence that most patients are overdiagnosed. The Italian National guidelines about organ acceptance from neoplastic donors changed in March 2005, extending the pool of potential candidates with CaP and introducing the function of a second opinion expert. Between 2001 and February 2005, 40 candidate donors with total PSA,10 and/or positive digital rectal examination underwent histopathological analysis of the prostate: 15 (37.5%) donors harboured CaP, and 25 (62%) were judged at ,standard risk'. After the introduction of the new guidelines in 2005, the second opinion expert judged at ,standard risk' 48 of 65 donors, while 17 of 65 needed histopathological analysis. Four (6.2%) donors harboured CaP, and 61 (94%) where judged at ,standard risk', with a significant increase of donated and actually transplanted organs. The application of the new guidelines and the introduction of a second opinion expert allowed a significant extension of the ,standard risk' category also to CaP patients, decreasing the histopathological examinations and expanding the donor pool. [source]

Identifying Combinations of Cancer Markers for Further Study as Triggers of Early Intervention

BIOMETRICS, Issue 4 2000
Stuart G. Baker
Summary. In many long-term clinical trials or cohort studies, investigators repeatedly collect and store tissue or serum specimens and later test specimens from cancer cases and a random sample of controls for potential markers for cancer. An important question is what combination, if any, of the molecular markers should be studied in a future trial as a trigger for early intervention. To answer this question, we summarized the performance of various combinations using Receiver Operating Characteristic (ROC) curves, which plot true versus false positive rates. To construct the ROC curves, we proposed a new class of nonparametric algorithms which extends the ROC paradigm to multiple tests. We fit various combinations of markers to a training sample and evaluated the performance in a test sample using a target region based on a utility function. We applied the methodology to the following markers for prostate cancer, the last value of total prostate-specific antigen (PSA), the last ratio of total to free PSA, the last slope of total PSA, and the last slope of the ratio. In the test sample, the ROC curve for last total PSA was slightly closer to the target region than the ROC curve for a combination of four markers. In a separate validation sample, the ROC curve for last total PSA intersected the target region in 77% of bootstrap replications, indicating some promise for further study. We also discussed sample size calculations. [source]

The presence of prostate cancer on saturation biopsy can be accurately predicted

BJU INTERNATIONAL, Issue 5 2010
Sascha A. Ahyai
Study Type , Diagnostic (non-consecutive) Level of Evidence 3b OBJECTIVE To improve the ability of our previously reported saturation biopsy nomogram quantifying the risk of prostate cancer, as the use of office-based saturation biopsy has increased. PATIENTS AND METHODS Saturation biopsies of 540 men with one or more previously negative 6,12 core biopsies were used to develop a multivariable logistic regression model-based nomogram, predicting the probability of prostate cancer. Candidate predictors were used in their original or stratified format, and consisted of age, total prostate-specific antigen (PSA) level, percentage free PSA (%fPSA), gland volume, findings on a digital rectal examination, cumulative number of previous biopsy sessions, presence of high-grade prostatic intraepithelial neoplasia on any previous biopsy, and presence of atypical small acinar proliferation (ASAP) on any previous biopsy. Two hundred bootstraps re-samples were used to adjust for overfit bias. RESULTS Prostate cancer was diagnosed in 39.4% of saturation biopsies. Age, total PSA, %fPSA, gland volume, number of previous biopsies, and presence of ASAP at any previous biopsy were independent predictors for prostate cancer (all P < 0.05). The nomogram was 77.2% accurate and had a virtually perfect correlation between predicted and observed rates of prostate cancer. CONCLUSIONS We improved the accuracy of the saturation biopsy nomogram from 72% to 77%; it relies on three previously included variables, i.e. age, %fPSA and prostate volume, and on three previously excluded variables, i.e. PSA, the number of previous biopsy sessions, and evidence of ASAP on previous biopsy. Our study represents the largest series of saturation biopsies to date. [source]

An artificial neural network for five different assay systems of prostate-specific antigen in prostate cancer diagnostics

Impact of prostate-specific antigen level and prostate volume as predictors of efficacy in photoselective vaporization prostatectomy: analysis and results of an ongoing prospective multicentre study at 3 years

BJU INTERNATIONAL, Issue 6 2006
ALEXIS E. TE
In a multicentre study from the USA, 3-year results of the high-power KTP laser prostatectomy are presented. The authors used preoperative PSA level as a marker of prostate volume and assessed its potential predictive value on the level of clinical efficacy for treating symptomatic BPH. They found that the overall results from the technique were positive and durable, and suggested that there was a significant difference in efficacy between patients presenting with a total PSA of <6 or >6 ng/mL. Many patients who have had a radical prostatectomy are followed for a prolonged period and several observations are presented from an Italian study of urinary incontinence. The authors present their detailed results, finding a considerable trend in incontinence and anastomotic stricture, which decreased over time. OBJECTIVE To report the 3-year results and analyse whether total prostate-specific antigen (tPSA) levels and prostate volume before treatment can predict the level of clinical efficacy of photoselective vaporization prostatectomy (PVP) for treating obstructive benign prostatic disease, as high-power potassium-titanyl-phosphate (KTP) laser prostatectomy was previously shown to be safe and to efficiently vaporize prostatic adenoma secondary to benign prostatic hyperplasia (BPH), with minimal bleeding and morbidity. PATIENTS AND METHODS From October 2001 to January 2003, 139 men (mean age 67.7 years, sd 8.7) diagnosed with obstructive lower urinary tract symptoms secondary to BPH, had PVP with an average 80 W of KTP laser energy, at six investigational centres. A subanalysis evaluating each patient for tPSA and prostate volume before PVP was conducted, with a long-term assessment of the primary efficacy outcomes at 3 years after PVP. Each patient was assigned to one of two subgroups according to the tPSA level (group 1, ,,6.0 ng/mL; group 2 ,,6.1 ng/mL) and evaluated separately. Each subgroup was assessed for changes from baseline in American Urological Symptom Index (AUA SI) score, quality of life (QoL) score, peak urinary flow rate (Qmax), prostate volume, and postvoid residual urine volume (PVR) at 1, 2 and 3 years after PVP. RESULTS All tPSA subgroups had a sustained improvement in all efficacy outcomes maintained through the 3 years. There was a statistically significant difference in the level of improvement between groups 1 and 2 (P < 0.05) in AUA SI and Qmax at 1, 2 and 3 years. The mean (sd) prostate volume for group 1 was 48.3 (16.7) mL (87 men), and was 83.1 (30.6) mL (52 men) in group 2. The mean percentage improvement in the AUA SI at 1, 2 and 3 years in group 1 and 2, respectively, was 86%, 92% and 85%, and 69%, 74% and 76%; the corresponding percentage improvement in Qmax was 194%, 185% and 179%, and 124%, 145% and 139%, respectively. Overall treatment efficacy in all patients evaluated showed a mean 83%, 79%, 71% and 165% improvement in AUA SI, QoL, PVR and Qmax, respectively. Adverse events were minimal and the re-treatment rate was 4.3%. CONCLUSIONS These results suggest that there is a significant difference in efficacy in patients with a tPSA of ,,6.0 ng/mL or ,,6.1 ng/mL before PVP. However, the overall results achieved with PVP were very positive and durable to 3 years, irrespective of tPSA level and prostate volume. [source]