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Total Prostate-specific Antigen (total + prostate-specific_antigen)
Selected AbstractsProstate-specific antigen adjusted for the transition zone volume as a second screening test: A prospective study of 248 casesINTERNATIONAL JOURNAL OF UROLOGY, Issue 7 2006SEOK-HO KANG Aim:, This study was conducted to verify the effectiveness of prostate-specific antigen adjusted for the transition zone volume (PSATZ), and its availability as a second screening test for prostate cancer detection. Materials and methods:, Total prostate-specific antigen (PSA) and free PSA was measured in male patients who visited our outpatient department for voiding difficulty or screening for prostate cancer. Patients who had an intermediate PSA level between 4.0 and 10.0 ng/mL, with an apparently normal prostate on a digital rectal examination, were enrolled. PSATZ, free-to-total PSA ratio (F/T ratio) and PSA density (PSAD) were calculated and statistical comparisons between biopsy-positive (cancer) and biopsy-negative patients (benign) were conducted. Results:, Of 248 patients, 51 (20.6%) had prostate cancer and 197 (79.4%) had benign prostatic hyperplasia (BPH) on pathologic examination. Mean PSA, PSAD, F/T ratio and PSATZ were 7.48 ± 1.77 ng/mL, 0.23 ± 0.09 ng/mL per mL, 0.14 ± 0.08 and 0.71 ± 0.44 ng/mL per mL in patients with prostate cancer and 6.59 ± 1.60 ng/mL, 0.16 ± 0.07 ng/mL per mL, 0.21 ± 0.11 and 0.36 ± 0.30 ng/mL per mL in patients with benign, respectively. Receiver operating characteristics (ROC) curve analysis demonstrated that PSATZ predicted the biopsy outcome better than F/T ratio. With a cut-off value of 0.37 ng/mL per mL, PSATZ had a sensitivity of 74.5% and a specificity of 72.6% for predicting prostate cancer. The maximal cut-off value that preserves 100% of sensitivity was 0.2, and at this cut-off value, 16.1% of unnecessary biopsies could be reduced. Conclusions:, Prostate-specific antigen adjusted for the transition zone volume may be more useful than other strategies in detecting prostate cancer in patients with intermediate PSA levels of 4.0,10.0 ng/mL. It can be used as a second screening test to reduce unnecessary biopsy. [source] Evaluation of molecular forms of prostate-specific antigen and human kallikrein 2 in predicting biochemical failure after radical prostatectomyINTERNATIONAL JOURNAL OF CANCER, Issue 3 2009Sven 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] ORIGINAL ARTICLE: Evaluation of Semen Detection in Vaginal Secretions: Comparison of Four MethodsAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2008Jennifer Flatow Culhane Problem, To determine the best method to detect semen in human vaginal secretions. Method of study, Vaginal secretions from 302 pregnant women at mean 11.8 weeks' gestation were analyzed. Semen detection was assessed with: (i) measurement of total prostate-specific antigen (PSA), (ii) acid phosphatase activity, (iii) microscopic measurement of spermatozoa on Gram stain, and (iv) self-reported sexual intercourse in the past 2 days. Sensitivity and specificity were calculated for each technique in comparison with PSA levels. Results, A total of 119 (39.4%) women had a detectable PSA. Compared with measurable PSA, the sensitivity and specificity for other methods were: acid phosphatase (26.9%, 98.4%), Gram stain (36.1%, 98.4%), and self-report of intercourse in the past 48 hr (41.9%, 88.8%). Conclusion, Compared with PSA levels, commonly used assays for recent semen exposure are inaccurate. This inaccuracy may affect the results of studies, which measure vaginal immune factors like cytokines or retrieve DNA from vaginal specimens. [source] Prostate-specific antigen levels in relation to cadmium exposure and zinc intake: results from the 2001,2002 national health and nutrition examination surveyTHE PROSTATE, Issue 2 2008Edwin van Wijngaarden Abstract BACKGROUND Cadmium exposure has been suggested as a risk factor for prostate cancer, and experimental literature suggests that the carcinogenic effect of cadmium is modified by the presence of zinc. We evaluated total prostate-specific antigen (PSA) levels in relation to urinary cadmium concentrations and dietary zinc intake. METHODS PSA levels were determined in 1,320 men over the age of 40 in the 2001,2002 National Health and Nutrition Examination Survey (NHANES). Urinary cadmium concentrations were measured in about one-third of the sample population, whereas dietary zinc intake was based on participants' 24-hr recall. Information on all three variables was available for 422 men in the 2001,2002 NHANES survey. We performed linear regressions to evaluate the relationships these factors after accounting for age and other covariates. RESULTS Little evidence for an association between cadmium and elevated PSA level was observed. However, the data provide suggestive evidence for an interaction between zinc intake and cadmium exposure (P for interaction,=,0.09). Among men with zinc intake less than the median level of 12.67 mg/day, an increase in 1 µg/g creatinine cadmium exposure was associated with a 35% increase in PSA level. In contrast, among men with greater than median zinc intake, little evidence for an association between cadmium and PSA was found. CONCLUSIONS These findings suggest a protective effect of zinc intake on cadmium-induced prostatic injury, and may provide further rationale for investigating the impact of these factors individually and jointly on the etiology of prostate cancer. Prostate 68: 122,128, 2008. © 2007 Wiley-Liss, Inc. [source] Identifying Combinations of Cancer Markers for Further Study as Triggers of Early InterventionBIOMETRICS, Issue 4 2000Stuart 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 predictedBJU INTERNATIONAL, Issue 5 2010Sascha 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] 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 yearsBJU INTERNATIONAL, Issue 6 2006ALEXIS 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] Discordant performance of assays for free and total prostate-specific antigen in relation to the early detection of prostate cancerBJU INTERNATIONAL, Issue 6 2001B.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] | ||||||||||