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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In summary, the 1997 revision of the ACS guideline for the early detection of prostate cancer is based on knowledge gained by a critical analysis of experience since the original version of 1992. This is only a milestone along a continuous journey rather than being the final destination. Other revisions will be considered when new knowledge becomes available, but for the present, this guideline is offered to health care professionals seeking to provide optimal care to asymptomatic men at risk for prostate cancer.
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PMID:American Cancer Society guideline for the early detection of prostate cancer: update 1997. 931 20

To describe general practitioners' current beliefs, knowledge and self-reported practices in prostate cancer screening, we conducted a national survey of 1,271 general practitioners, obtaining 855 completed questionnaires (67% response rate). Available tests for prostate cancer screening, namely DRE and PSA alone and in combination, were indicated to be effective by 49%, 43% and 68% of respondents respectively, with older GPs significantly more likely to hold these views. The effect of guidelines was mixed. Less than 8% of respondents indicated they did not recommend screening. Although the majority of GPs were unlikely to adopt an opportunistic approach to prostate cancer screening, 63%, 57% and 46% indicated they would recommend DRE, PSA or both respectively during a dedicated health check up. Awareness of relevant guidelines was low, with nearly half of respondents unable to recall publications from the RACGP or ACS. Counter-intuitively, awareness of ACS guidelines for prostate cancer screening (which advise against screening) was significantly associated with the converse behaviour. Findings from this first national study behove proactive and highly targeted dissemination in general practice of the AHTAC policy announced by the Commonwealth Health Minister in August 1996.
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PMID:Australian general practitioners' views and use of tests to detect early prostate cancer. 962 25

Serum prostate specific antigen (PSA) levels were measured using an ACS-PSA kit in 147 systematic biopsy cases (61 with prostate cancer (PC)) and 96 transurethral resection of prostate (TUR-P) cases (2 with PC). In the 147 biopsy cases, the sensitivity for PSA using 3.0 and 10.0 ng/ml as cut-off values was 91.8 and 90.2%, while the specificity was 9.30 and 30.2%, respectively. The sensitivity for PSAD (A) (calculated by transabdominal ultrasound) using 0.25 and 0.5 ng/ml/cm3 as cut-off values was 91.8 and 90.2%, while the specificity was 22.1 and 50.0%, respectively. These data indicated that PSAD (A) provided better information for detecting PC than PSA alone. No statistical difference was found between PSAD (A) and PSAD (R) (calculated by transrectal ultrasound) in the utility of detecting PC. PSA below 15.0 ng/ml was seen in sixteen patients with PC. Five of these sixteen patients had a PSA level of < 3.0, and they underwent prostate biopsy based on the abnormality by digital rectal examination (DRE). The other eleven patients had PSAD (A) level of > 0.3 ng/ml/cm3. In all 243 cases, PC was not found in the 49 patients (PSA < 3.0 ng/ml) or 91 patients (PSAD (A) < 0.25 ng/ml/cm3) who had no abnormal findings by DRE and transabdominal ultrasonography. These results suggested a criterion in the use of the ACS-PSA kit for the indication of prostate biopsy and TUR-P.
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PMID:[Clinical evaluation of chemiluminescence immunoassay PSA (ACS-PSA) for detection of prostate cancer]. 975

Renal cell carcinoma (RCC) is the most common form of cancer affecting the kidney. There is currently no biochemical marker for this disease. We have shown that serum-immunoreactive prostate-specific antigen (PSA) levels, as measured by the two-site Ciba-Corning ACS:180 immunochemiluminometric assay, are elevated in women with RCC. Although the levels were low (0.13-0.89 microgram/l), serum PSA was clearly measurable prior to surgery in 13 of 17 women (76%) with RCC. Significantly, the PSA levels fell to undetectable after nephrectomy. Seventeen normal women also had undetectable (<0. 1 microgram/l) PSA levels. Two women, who had several serum PSA measurements performed postoperatively, showed a t(1/2) of 2-3 days equivalent to that observed for PSA in men following radical prostatectomy for prostate cancer. The 17 RCCs evaluated in this study consisted of 10 stage A, 4 stage B, and 3 stage C tumors. There was no relationship between tumor size, stage, or serum-immunoreactive PSA level, although the majority of these tumors are low grade. We have shown by reverse transcription-PCR, using PCR primers directed to the NH2 terminal coding region of the KLK3 (PSA) gene and the closely related KLK1 and KLK2 genes, that these genes are not expressed in these tumors. Our findings show, however, that elevated levels of a circulating PSA-like protein are present in women with RCC.
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PMID:A prostate-specific antigen-like protein associated with renal cell carcinoma in women. 981 28

Prostate specific antigen (PSA) is a glycoprotein found in the epithelial cells of the prostatic duct and acini. PSA is elevated in all four stages of prostate cancer as well as in benign prostatic hypertrophy. We evaluated a new chemiluminescent assay for PSA by comparing this assay with the microparticle enzyme immunoassay for PSA (MEIA) on the AxSYM analyzer (Abbott Laboratories, Abbott Park, IL) and a Hybritech Tandem R assay for PSA. The new chemiluminescent assay is recently available from Bayer Diagnostics (Tarrytown, NY) and can be run using the ACS: 180 Plus analyzer. Precision of the new chemiluminescent assay was evaluated using commercially available controls (Bayer Diagnostics). The within-run and total CVs were 6.4 and 8.7% for the low control (mean: 0.43 microg/L), 1.6 and 5.2% for the next level control (mean:1.94 mg/L), 4.3 and 4.9% for the medium control (mean: 2.10 mg/L), 1.2 and 3.9% for the high control 1 (mean: 11.52 mg/L), and finally 3.2 and 6.9% for the high control 2 (mean: 21.52 mg/L). The spike recovery varied from 94.2 to 109.6% for five different specimens we studied. We also observed excellent dilution recoveries. For example, in the specimen supplemented with 3.02 mg/L of PSA, the dilution recoveries were 102. 1, 104.7, and 103.7% for 1:2, 1:4, and 1:8 dilutions, respectively. We analyzed 113 serum specimens from patients with various concentrations of PSA (range 0.5 mg/L-2040 mg/L) using the new chemiluminescent assay and compared our results with the MEIA and Hybridtech (Tandem-R PSA) assays. Using x axis as the PSA concentrations obtained by the Tandem-R assay and the y axis as the PSA values obtained by the new chemiluminescent assay, we observed the following regression equations: y = 1.04 x -0.19 (r = 0.99, n = 112). One specimen with PSA concentrations of 2040 microg/L by the MEIA and 2156 microg/L by the chemiluminescent assay was not used for regression analysis. Similarly using x axis as the PSA concentrations obtained by the MEIA assay and y axis as the PSA concentrations obtained by the chemiluminescent assay, we observed the following regression equation: y = 0.88 + 0.02 (r = 0.99, n = 112). We conclude that the new chemiluminescent assay has excellent precision and the results compared well with the existing assays.
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PMID:Performance evaluation of a new chemiluminescent assay for prostate specific antigen. 1090 69

This prospective, multicenter European Prostate Cancer Detection study evaluated the value and performance of the molecular forms of prostate-specific antigen (PSA) and their derivatives in combination with prostate gland and transition zone volumes in early detection of prostate cancer in patients with PSA levels between 4 and 10 ng/mL. Of 750 men enrolled at 7 different European urology centers into the study between November 2001 and March 2002, 340 (45.3%) had a total PSA (tPSA) between 4 and 10 ng/mL (age range, 46 to 87 years). In all patients, the ratio of complexed PSA (cPSA) to tPSA (c/tPSA), cPSA density (cPSAD), cPSAD of the transition zone, PSA, free PSA (fPSA), ratio of fPSA to tPSA (f/tPSA), tPSA density (PSAD), and PSAD of the transition zone were measured and collected 5 to 10 minutes before the sextant biopsy with 2 additional transition zone cores. Measurements of tPSA and fPSA were done with the AxSYM test, whereas cPSA was measured with the ACS 180 cPSA assay. All patients had a transrectal ultrasound-guided sextant prostate biopsy, and 2 additional transition zone biopsies and total and transition zone volumes were measured at the time of biopsy. Histopathologic findings revealed benign histology in 237 patients and prostate cancer in 103 patients (69.7% and 30.3%, respectively). Statistically significant differences included larger total volumes, larger transition zone volumes, and f/tPSA in patients with benign disease (P = 0.0009, P <0.0001, P <0.0001, respectively). At 90% and 95% sensitivity, specificity of cPSA was significantly greater than that for PSA (P <0.0001). At sensitivity levels of 90% and 95%, the specificity of the cPSA assay using cutoff values of 3.06 and 2.52 ng/mL was 20.3% and 9.1%, respectively. A cPSA cutoff value of 6.95 ng/mL and 7.57 ng/mL afforded 90% and 95% specificity for detecting prostate cancer. The area under the curve (AUC) in the receiver operating characteristics curve of cPSA was statistically significantly higher compared with tPSA (60.8 vs 56.9, P = 0.032). AUC for volume-related parameters PSAD, cPSAD, PSAD of the transition zone, and cPSAD of the transition zone were 62.8%, 63.1%, 63.0%, and 63.6%, respectively. cPSA performs better than tPSA in the differentiation between benign disease and prostate cancer and provides similar information to the f/tPSA ratio. In addition, cPSA and cPSA volume-related parameters (cPSAD, cPSAD of the transition zone) further improved the specificity of PSA in early detection of prostate cancer.
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PMID:Complexed prostate-specific antigen, complexed prostate-specific antigen density of total and transition zone, complexed/total prostate-specific antigen ratio, free-to-total prostate-specific antigen ratio, density of total and transition zone prostate-specific antigen: results of the prospective multicenter European trial. 1238 56

Prostate-specific antigen (PSA) has emerged as the most predictive test of whether or not a man has prostatic carcinoma. The free to total PSA ratio provides important enhancement in specificity, thus obviating unnecessary negative biopsies. In the absence of an international standard for total PSA, much less free PSA, variation between manufacturers may cause confusing results. We sought to compare three different manufacturer's free and total PSA assays in a population consisting of consecutive patients who had PSA testing in a reference laboratory in Germany. Between April 1994 and July 1996, serum specimens from 240 men were evaluated with three different free and total PSA assays. Indications for PSA determination were based on the referring physician, who also provided the clinical diagnosis. Total and free PSA were measured on the same freeze-thaw cycle with Chiron Diagnostics, Enzymun Boehringer Mannheim, and Hybritech Tandem-R assays. Seventy-nine men had carcinoma of the prostate, 120 had clinical evidence of benign prostatic hyperplasia and 27 were without evidence of prostatic disease. The Chiron ACS: 180 free to total ratio compared very well with the Tandem-R assay at the 95% sensitivity level, affording 17 and 22% specificity respectively. Using the range of total PSA of 4-10 ng/ml, the increase in specificity of the free to total PSA is quite significant, and the specificity of the Enzymun assays is greatly improved. (Specificity of 49%, 29% and 25% at 95% sensitivity for ACS, Enzymun and Tandem respectively.) This data, based on 'real world' clinical experience, shows significant variation between different manufacturers' assays. There was significant equivalence between the Chiron and Hybritech assays. The Enzymun assay performed well only when data from the total PSA range of 4-10 ng/ml was included. Clinicians must be aware of which manufacturers' assays for both the free and total PSA their laboratory staff is utilizing, and laboratory technicians must provide meaningful outcome data based on the patient population they serve with respect to the performance of these assays.
Prostate Cancer Prostatic Dis 1998 Dec
PMID:A comparison of three free and total PSA assays. 1249 75

Nonequimolar-response assays for prostate-specific antigen (PSA) are criticized for overestimating total PSA in some men without prostate cancer (PCA), and underestimating total PSA in some men with PCA. We recently studied three nonequimolar-response PSA assays that had undergone modifications. While two of the studied assays achieved equimolar-response characteristics with improved areas under receiver operating characteristic (ROC) curves (AUC), the modification of the Chiron ACS PSA assay (ACS PSA2, Chiron) failed to achieve this. Recently, the ACS assay underwent another modification (ACS PSA, Bayer), which we investigated. Sera from 305 men (155 without and 150 with PCA, PSA > or = 2 and < or = 30 microg/l, Tandem-E) were measured using both modifications of the ACS assay and equimolar-response reference methods (Tandem-R free and Tandem-E, Hybritech). Molar response relative to the reference method and clinical performance (comparison of AUCs) between the previous and new ACS assay modifications were studied. The new modification of the ACS assay (ACS PSA, Bayer) achieved equimolar-response characteristics but reported lower values (average 10%) than the Tandem-E assay. Compared to the previous modification (ACS PSA2, Chiron), a 3% improvement in AUC (p = 0.01) was found. Using results of the redesigned equimolar-response assay (ACS PSA, Bayer), we calculated that 6 of 155 men without PCA in this sample set could be spared unnecessary biopsy compared with the previous nonequimolar-response assay (ACS PSA2, Chiron) without missing additional PCA (90% sensitivity). These data provide additional evidence for clinical advantages of equimolar-response over nonequimolar-response PSA assay formats.
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PMID:A new modification of the Chiron ACS assay for total prostate-specific antigen achieves equimolar response characteristics and improves the detection of prostate cancer. 1263 56

Although prostate specific antigen (PSA) is widely used in the discrimination of benign prostatic hyperplasia (BPH) and prostate cancer, its diagnostic value is controversial due to an appreciable false positive rate. In the present study, we compared a recently introduced assay method, equimolar PSA measurement, to non-equimolar PSA measurement and also determined the diagnostic value of percent free PSA with changing total PSA (tPSA) measurements. Between April 1999 and December 2001, the sera of 61 patients with BPH and 41 with prostate cancer were examined. Total PSA and free PSA was determined using the Immulite 2000 assay system, whereas equimolar tPSA measurement was performed using Bayer PSA Q for the Chiron ACS 180 system. Comparative analysis of the two different assays revealed better diagnostic sensitivity and specificity values for equimolar tPSA measurement, which in turn would have led to 10% of the patients avoiding an unnecessary biopsy. Additionally, percent free PSA with the changing denominator of tPSA assays showed that the free PSA/equimolar tPSA ratio was the best tumor marker among the studied forms of PSA. It was concluded that equimolar tPSA measurement using recombinant Fab fragments is superior to the classical measurements with monoclonal antibodies, and that the use of percent free PSA with the equimolarly measured tPSA has better sensitivity and specificity in the discrimination of benign and malignant diseases of the prostate.
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PMID:Increased discrimination between benign prostatic hyperplasia and prostate cancer with equimolar total prostate specific antigen measurement. 1275 94

Prostate-specific antigen (PSA), the most important tumor marker for the detection of prostate cancer, exists in serum in a free, uncomplexed form (free PSA [fPSA]), and as bound to protease inhibitors (mainly alpha1-antichymotrypsin [ACT]). The measurement of complexed PSA (cPSA) concentration in serum has been shown to have better sensitivity and specificity than serum total PSA concentration. A new chemiluminescent immunoassay for cPSA for use on the Bayer ACS:180 fully automated system (Bayer Corp, Tarrytown, NY) has been developed and evaluated. The precision of the new assay was <3.9% (within-run coefficient of variation [CV]) and <5.0% (total CV). The analytical sensitivity (95% upper limit of noise at zero calibrator) was <0.03 ng/mL. A comparison of the ACS:180 cPSA results with the cPSA concentrations calculated from the ACCESS (Beckman-Coulter) PSA and fPSA assays yielded the following regression equation: ACS:180 cPSA=0.93* (calculated ACCESS cPSA)+0.43, R=0.993, n=95. The mean dilution and spike recovery for five samples were both 98%. No interference was observed from hemoglobin, triglyceride, or bilirubin (NCCLS protocol). These results indicate that the ACS:180 cPSA assay is precise, and compares well with the calculated cPSA from ACCESS total and free-PSA results.
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PMID:Evaluation of an automated chemiluminescent immunoassay for complexed PSA on the Bayer ACS:180 system. 1293 46


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