Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a study population, can digital rectal examination (DRE), transrectal ultrasound (TRUS), and prostate specific antigen (PSA) (monoclonal) effectively detect the majority of clinically relevant cancer? If this is possible, the remaining patients could then be considered for chemopreventive protocols. The American Cancer Society/National Prostate Cancer Detection Project (ACS/NPCDP) had a cancer detection rate of 2.4% for its initial year utilizing PSA, DRE and TRUS. TRUS and PSA detected 73% more cancer than DRE alone. TRUS detected a greater percentage of cancers than DRE (85% vs. 64%). PSA was > or = 4 ng/ml for 66% of prostate cancer patients; 11% of cancer patients had PSA < 2 ng/ml. PSA decision levels based on gland volume detected a subgroup at the 95th percentile that had a nine-fold increased risk for cancer. In a separate study differentiating benign prostatic hypertrophy (BPH) and cancer, we found 0.12 +/- 0.13 ng/ml/gm for serum PSA (sPSA)/gm BPH. This study proved that predicted PSA (pPSA) = gland volume x 0.12; this equation also functioned at the 95th percentile for any individual patient. Individual patient assessment: 1. Entry level PSA = 2 ng/ml. 2. Those patients with PSA > 2 ng/ml have TRUS determination of gland volume (performed by technician). 3. pPSA = gland volume x 0.12. If sPSA > pPSA then: 4. (sPSA-pPSA)/2 = predicted volume (cc) of cancer; 5. 3 square root of volume of cancer = mean diameter (cm) of cancer. Thus, these results should detect the majority of clinically relevant cancer (> 0.5 cc). PSA combined with TRUS and DRE can identify high risk groups for cancer.
 ...
PMID:The role of digital rectal examination, transrectal ultrasound, and prostate specific antigen for the detection of confined and clinically relevant prostate cancer. 128 97

Magnetic resonance imaging was utilized in 18 patients with prostatic cancer and compared with the findings in normal volunteers (Pontes et al., 1985), benign prostatic hyperplasia (Hricak et al., 1983), acute prostatitis (Walsh and Jewett, 1980) and chronic prostatitis (ACS, 1986). Sixteen of the 18 patients with carcinoma demonstrated inhomogeneous signal intensity, however, a similar appearance was also seen in 5 patients with benign prostatic hyperplasia. It does not appear that magnetic resonance imaging is able to reliably differentiate benign from malignant prostatic disease. Extra-prostatic tumor extension and pelvic adenopathy was demonstrated and the technique offers promise for the pre-operative staging of patients with known prostatic carcinomas.
 ...
PMID:Magnetic resonance imaging of the prostate. 244 26

Prostate-specific antigen (PSA) in serum is primarily complexed with alpha 1-antichymotrypsin (alpha 1-ACT). However, 12-15% of prostate cancer (PCa) patients present with the predominant form being uncomplexed (free) PSA (Lilja et al., Clin Chem 1991;37:1618-24). We report that commercial immunoassays demonstrate variations in reactivity, especially to the uncomplexed form. We fractionated and analyzed commercial controls, PSA complexes prepared in vitro, and sera from patients with PCa or benign prostatic hyperplasia, using molecular sieve chromatography and Hybritech Tandem-R, Abbott IMx, and Ciba Corning ACS PSA assays. Peak integration of PCa samples demonstrated ACS:Tandem-R ratios of 1-1.3 for PSA/alpha 1-ACT complex. In contrast, ratios of uncomplexed peaks ranged from 2 to 4, suggesting a greater reactivity of the uncomplexed form in the ACS PSA assay. Discrepancies between assays, when PSA was measured in unfractionated sera, correlated directly with the percentage of the uncomplexed form. In controls, fractionation revealed the presence of uncomplexed PSA only, with ratios of ACS:Tandem-R and IMx:Tandem-R of 3:1 and 1.8:1, respectively. Immunoblots of PCa sera detected uncomplexed PSA (approximately 30 kDa) and PSA complexes of approximately 95 kDa (PSA/alpha 1-ACT) and > 200 kDa, indicative of alpha 2-macroglobulin. Maximal recognition of all forms of PSA may be important for early detection of disease progression.
 ...
PMID:Multiple forms of prostate-specific antigen in serum: differences in immunorecognition by monoclonal and polyclonal assays. 752 44

This paper summarises the results of a comparison of the Serono SR1, Ciba Corning ACS 180, Abbott IMx and Hybritech Tandem-R prostate-specific antigen assays. One hundred serum pools were assayed using the four methods. Linear regression analysis of the data showed that, although overall correlations were good, different assays gave different prostate-specific antigen concentrations. Tandem-R and SR1 assays gave very similar prostate-specific antigen values; in general, the ACS assay gave higher prostate-specific antigen values than the IMx assay gave lower prostate-specific antigen values than the established Tandem-R assay. Following fractionation of serum from prostate cancer patients, all immunoassays detected several immunoreactive prostate-specific antigen forms. The major immunoreactive form (> 88% of immunoreactivity) had an apparent molecular size of M(r) approximately 100,000 and is likely to be a complex of prostate-specific antigen with alpha 1-antichymotrypsin; two minor forms had apparent molecular sizes of M(r) approximately 30,000 (probably free prostate-specific antigen) and 200,000 (probably prostate-specific antigen complexed to high molecular mass anti-proteases). From this study there is no evidence that polyclonal/monoclonal antibody immunoassays are to be preferred to monoclonal/monoclonal antibody immunoassays for the determination of free prostate-specific antigen in serum.
 ...
PMID:Measurement of prostate-specific antigen in serum using four different immunoassays. 751 58

We examined by gel filtration chromatography (Sephacryl 200) sera from 73 untreated patients with peripheral zone prostatic cancer volumes of 1 to 17 cc as well as patients with clinical stages C and D2 cancer. We also examined the sera from 40 patients who had failed radiation or hormonal therapy to determine if clonal cell selection by these 2 therapies altered the binding of prostate specific antigen (PSA) to alpha 1-antichymotrypsin. Finally, we compared sera from 10 patients with benign prostatic hyperplasia (BPH) and 14 with large transition zone-BPH cancer. Without exception, of the total serum PSA recognized by the Hybritech Tandem-R, Yang Pros-Check, Abbott IMx and Ciba Corning ACS assays, 88 to 98% were complexed with alpha 1-antichymotrypsin in all cancer patients. The 10 patients with BPH showed less complexation (73 to 84%). These studies suggest that much of the quantitative differences among assays is determined more by relative differences in recognition of the free and complex forms of PSA than by calibration differences between assays.
 ...
PMID:Serum prostate specific antigen binding alpha 1-antichymotrypsin: influence of cancer volume, location and therapeutic selection of resistant clones. 752 8

Prostate cancer represents an increasing public health burden that may be controlled by early detection interventions. Several studies using transrectal ultrasound (TRUS), prostate-specific antigen (PSA), and digital rectal examination (DRE) in men without known prostate disease have been reported. Recent studies are reviewed, and recent preliminary results of the American Cancer Society-National Prostate Cancer Detection Project (ACS-NPCDP) are presented. Results show that the rate of early prostate cancer detection can be increased by coordinated use of TRUS, PSA, and DRE. The ACS-NPCDP data indicate that the positive predictive value of recommendations to biopsy is improved when based on a combination of studies. Examination by TRUS alone is least specific and least cost-effective, whereas the combination of PSA and DRE is less costly and more specific with equal sensitivity to cancer. Additional data are needed to determine if prostate cancer death rates will be altered by early detection interventions. Physicians and patients need to be informed of the possible risks and benefits of early detection interventions.
 ...
PMID:The status of prostate cancer early detection. 768 18

In a recent AUA/ACS scientific seminar, experts on prostate cancer met to present and discuss information concerning the detection and treatment of early-stage prostate cancer. This article provides an overview of the major topics covered, including perspectives on the problem, proposed clinical studies, diagnosis and prognostic factors, treatment studies, cancer control, and future directions.
 ...
PMID:Report on the American Urologic Association/American Cancer Society scientific seminar on the detection and treatment of early-stage prostate cancer. 812 8

To study immunorecognition of free type and complex type prostate-specific antigen (PSA) by current commercial PSA assays, sera from 3 patients with stage D2 prostate cancer were separated by Sephacryl S-200 chromatography and determined by Delfia PSA, ACS-PSA and Eiken PA kits. Two antibodies used in the 3 kits are 2 monoclonal, 1 monoclonal and 1 polyclonal and 2 polyclonal antibodies, respectively. Following chromatography, two PSA peaks were obtained in all patients. One was about 100 kDa and the other about 30 kDa. The former was considered to be the complex type PSA (complex with alpha-1 antichymotrypsin) and the latter to be free type PSA. As to free type PSA, the ACS-PSA kit and Eiken PA kit quantitated PSA values approximately 5.1 and 2.5 times higher than the Delfia PSA kit. For complex type PSA, the quantity determined by ACS-PSA kit was approximately 1.3 times higher than that determined by the Delfia PSA kit, while the quantity determined by the Eiken PA kit was about one third of that determined by Delfia PSA kit. The ratio of complex type PSA to total PSA (free type PSA + complex type PSA) was 74.8 +/- 14.9% (mean +/- SD) when determined by Delfia PSA kit, 59.3 +/- 18.4% by ACS-PSA kit and 52.9 +/- 13.8% by Eiken PA kit. The range of this ratio determined by ACS-PSA kit was from 47.3% to 80.5% in the 3 patients. These findings suggest that there are qualitative differences in immunorecognition of free type PSA and complex type PSA among current commercial PSA assays and that there are quantitative differences in the ratio of the 2 forms of PSA in serum among prostatic cancer patients. The measurement and follow-up of both free type and complex type PSA might be important for diagnosis and monitoring of prostate cancer.
 ...
PMID:[Determination of free type and complex type prostate-specific antigen (PSA): differences in immunorecognition by Delfia PSA, ACS-PSA and Eiken PA kits]. 869 60

As a significant public health problem, prostate cancer meets nearly all the criteria for screening. While concerns about incomplete natural history, progression rates and need for better prognostic factors are valid, important social and public health issues also need consideration. If future expenditures for terminal cancer care are minimized via reductions in therapy choices or coverage, no economic benefit for prostate cancer screening should exist. Narrowly focused attempts at cost reduction could inappropriately discourage highest risk groups from participating in early detection programs, thereby eliminating the greatest potential benefit of screening. The ACS-NPCDP has demonstrated that early detection of prostate cancer produced distinct stage migration to earlier, more curable disease through optimized use of DRE, TRUS and PSA. PSA is the most objective test and detects tumors of significant biologic potential. Current cost savings are possible with improved public health education about the appropriateness of early detection in the oldest age groups or those with significant pre-existing medical conditions. Prostate cancer control perhaps requires a tailored approach of screening in high risk groups and more appropriate "case finding" in the lower risk general population. The initial combination of PSA and DRE represents an ethical and economical choice for individual patients consulting with informed physicians.
 ...
PMID:The American Cancer Society's National Prostate Cancer Detection Project. 885 93

The ACS National Prostate Cancer Detection Project was established in 1987 to demonstrate the feasibility of early detection as a cancer control strategy for prostate cancer. Ten years later, the compliance results suggest that early detection programs can achieve long-term participation in a healthy population.
 ...
PMID:The American Cancer Society National Prostate Cancer Detection Project and National patterns of prostate cancer detection and treatment. 931 21


1 2 3 4 5 6 7 8 9 10 Next >>