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

The usefulness of the fPSA fraction in the differential diagnosis of benign prostate hyperplasia (BPH) and prostate cancer was evaluated, with the aim of improving the diagnostic efficacy of PSA. Serum PSA and fPSA determinations were performed by an enzymoimmunoassay technique on an ES-300 system. fPSA constitutes a minor fraction both in normal subjects and in patients with prostate disease, being significantly lower in patients with untreated prostate cancer than in patients with BPH. Likewise, the authors have observed that the sensitivity of the fPSA/PSA ratio has an inversely proportional relationship with the stage of the disease. The results obtained in patients with PSA levels between 4 and 20 micrograms/l are also of note. In this series of patients, the efficacy of the fPSA/PSA ratio was higher than that of PSA, showing a sensitivity of 44% and a specificity of 95% at the cut-off of 0.08.
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PMID:Clinical usefulness of free PSA fraction as an indicator of prostate cancer. 884 33

Sonographic estimates of prostate volume have been applied to the diagnosis and management of prostate cancer. However, we have observed wide variation between transrectal sonographic estimates of prostate volume (TRUS-V) and the corresponding volumes of unfixed radical prostatectomy specimens (P-V). Because TRUS-V may influence the management of men with prostate disease, the relationship between TRUS-V and P-V was characterized for 100 consecutive men undergoing a radical retropubic prostatectomy (RRP). For the entire cohort, TRUS-V (35.9 +/- 16.9 mL) underestimated P-V (45.4 +/- 22.9 mL, p < .01). Mean signed percentage error between TRUS-V and P-V was -16 +/- 32%. The relationship of TRUS-V to P-V was volume dependent (p < .001). For volumes (P-V) < 30 mL, TRUS-V overestimated P-V. For volumes (P-V) > 30 mL. TRUS-V increasingly underestimated P-V. In summary, transrectal ultrasound estimates of prostate volumes differ significantly from the volume of unfixed RRP specimens. The direction and magnitude of TRUS-V error is volume dependent. Applied clinically, treatment paradigms employing prostate-volume-dependent management algorithms derived from nonuniform methods of volume estimation may not accurately reflect volume nomograms derived from uniform methods of measurement, and thus alter patient management.
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PMID:The accuracy of transrectal ultrasound prostate volume estimation: clinical correlations. 890 81

The development of monoclonal antibodies directed against prostatic kallikrein hK2 prompted us to evaluate its content, along with that of hK3 (prostate-specific antigen), in human prostate carcinoma. Seventy tumors categorized according to the M.D. Anderson Hospital classification (grade I to IV) were analyzed by immunohistochemistry. The staining intensity or the kallikrein content of benign prostatic hyperplasia glandular tissue (used as control) and of grade I tumors appeared similar. In grade II to IV tumors, histochemical data revealed highly variable hK2 or hK3 content in approximately 25% of tumors. Such patterns are consistent with a current observation related to heterogeneity of prostate tumors. In addition, a few tumors did not express hK3 (n = 3), hK2 (n = 3), or both (n = 3), indicating that some growth patterns of prostatic neoplasia are associated with a lack of secretion or storage of hK3 or hK2 for immunodetection. This statement also appears relevant to metastases. It was interesting to note that 4% of hK3-negative tumors had detectable hK2. Because of the importance of hK3 as a serum marker of prostate disorder, this study addresses for the first time the question of the relative importance of both hK3 and hK2 in the immunohistochemical diagnosis of prostatic tumors. We conclude that hK2 may add new information to prostate cancer diagnosis and characterization.
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PMID:Immunohistochemical study suggesting a complementary role of kallikreins hK2 and hK3 (prostate-specific antigen) in the functional analysis of human prostate tumors. 903 61

The introduction of prostate-specific antigen (PSA) testing into clinical medicine in 1986 revolutionized the management of patients with prostate cancer. The major limitation of this tumor marker stems from its inability to provide a clear distinction between benign prostate disease and prostate cancer, especially in patients with upper limit of normal or slightly increased PSA values. Recent research has established that PSA exists in the serum in several molecular forms. Patients with benign prostatic hyperplasia have more of the free form, whereas those with prostate cancer have more of a complexed form (PSA covalently bound to alpha 1-antichymotrypsin). Several investigations have now confirmed that determining percent free PSA (proportion of free PSA to total PSA) enhances the ability of PSA testing to distinguish between prostate cancer and benign prostatic hyperplasia. In addition, percent free PSA seems to have the greatest clinical significance in patients whose total PSA values range from 2.5 or 3.0 ng/mL (lower limit) to 10.0 ng/mL (upper limit). When the total PSA value is in the normal range (2.5 or 3.0 to 4.0 ng/mL), percent free PSA makes PSA a more sensitive test (increases cancer detection). When the total PSA level is minimally increased (4.1 to 10.0 ng/mL), percent free PSA makes PSA a more specific test (eliminates performance of unnecessary prostate biopsies). Although further work remains, it seems that percent free PSA can substantially improve the clinical utility of the PSA test for detecting early, curable prostate cancer.
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PMID:Percent free prostate-specific antigen: entering a new era in the detection of prostate cancer. 912 Nov 81

This study describes the value of using the fraction of free prostate-specific antigen as a further marker in the early detection of prostate cancer. This newly introduced marker is compared to the usual battery of age-dependent total prostate-specific antigen, prostate-specific antigen density (microg/l x g tissue) and prostate-specific antigen velocity (microg/l x year). Determination of total prostate-specific antigen and free prostate-specific antigen was performed on fresh serum samples obtained from 3470 symptomatic patients aged 45-80 attending the Urology Clinics, or their General Practitioners. Among them, 310 patients had total prostate-specific antigen above the age-dependent cut-off, and/or free/total prostate-specific antigen under 11%, with different prostate-specific antigen densities and velocities. Only 147 patients complied to undergo biopsy: in 72 of those patients, benign prostatic disease was histologically confirmed, while in 75 patients primary prostate cancer was histologically confirmed. Total and free prostate-specific antigen levels were determined using the third generation DPCs prostate-specific antigen assay performed on the Immulite automated immunoassay instrument. Total prostate-specific antigen age reference values were adopted from Oesterling et al. (J Am Med Ass 1993; 270:860-4); the prostate-specific antigen density was considered suspicious of prostate cancer if it was greater than 0.15 microg/l prostate-specific antigen per gram tissue (Seaman et al. Urol Clin N Am 1993; 20:653); prostate-specific antigen velocity greater than 0.75 microg/l x year (Carter et al., J Am Med Ass 1992; 267:215) was considered suspicious for prostate cancer. Of the 147 patients, 75 had prostate cancer and 72 had benign prostatic hypertrophy. The difference between prostate cancer and benign prostatic hypertrophy was significantly reflected only by free/total prostate-specific antigen and prostate-specific antigen velocity. These parameters also provided the best sensitivity and specificity. Only these parameters proved to be significant when using a backwards logistic regression model (prostate-specific antigen velocity, p = 0.007 odds ratio 2.782; free/total prostate-specific antigen %, p = 0.016 odds ratio 2.678). Combinations of various parameters became significant when including free/total prostate-specific antigen, increasing prostate cancer detection to 88%. We conclude that free/total prostate-specific antigen is the most significant among prostate-specific antigen quantities (total age-dependent prostate-specific antigen, prostate-specific antigen density and prostate-specific antigen velocity). Adding this parameter to other prostate-specific antigen parameters improves the discrimination between prostate cancer and benign prostatic hypertrophy for the population at risk.
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PMID:The additional value of free prostate specific antigen to the battery of age-dependent prostate-specific antigen, prostate-specific antigen density and velocity. 922 32

KLK1/tissue kallikrein is a member of a family of structurally related serine proteases which exhibit a diverse range of enzymic activities. Other members of this family of genes and the bradykinin (B2) receptor have been implicated in cancer processes. The KLK genes are expressed in various organs of the reproductive tract, including the prostate and uterus. In this study, we have examined whether KLK1/tissue kallikrein and the B2 receptor were both expressed in cancers emanating from these organs. We have shown that KLK1/tissue kallikrein and the B2 receptor are expressed, to varying degrees, in prostate disease and 2 human prostate cancer cell-lines, LNCaP and DU145. KLK1 is also expressed in a range of endometrial cancers, although at lower levels than that observed for normal human endometrial tissues. These findings suggest that a functional kallikrein-kinin system is present in prostate disease, in particular, which may be important in the process of tumorigenesis in this tissue.
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PMID:Tissue kallikrein and the bradykinin B2 receptor are expressed in endometrial and prostate cancers. 922 49

The objective of this study was to find a biomarker, easily detectable and measurable, that could be useful to the physician for the diagnosis and management of prostate cancer. An immunoaffinity-purified polyclonal antibody to the 5 alpha-reductase type 2 isozyme was prepared following standard procedures in New Zealand White rabbits. One hundred and seven urine samples were examined for the presence of this isozyme by Western blot, dot blot, and enzyme-linked immunosorbent assay assays. In a control group of 91 subjects (46 females and 45 males) with no history of prostate disease, only 1 female tested positive. In a test group of 16 males, 4 males with adenocarcinoma of the prostate under treatment with lupron/flutamide tested negative. Four males with untreated adenocarcinoma of the prostate tested positive. Two males with transitional cell carcinoma invading the prostatic ducts and two males with basal cell hyperplasia of the prostate with intraductal dysplasia tested positive. These results support the need for an extended study to explore the use of the Western blot or the simple dot blot and enzyme-linked immunosorbent assays for the detection of 5 alpha-reductase type 2 in urine as a potential marker for prostate disease.
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PMID:Preliminary evaluation of 5 alpha-reductase type 2 in urine as a potential marker for prostate disease. 938 16

We have established a procedure for the production of milligrams of free PSA (fPSA) from LNCaP cells derived from a human carcinoma of the prostate. By growing LNCaP cells in a serum-free medium in the presence of a synthetic androgen (R1881) and taking advantage of the special design of the Micro-mouse Hollow Fiber Bioreactor, relatively pure fPSA could be obtained. We found that columns containing either Sephacryl S-100 or S-200 could be used to remove the small amount of bovine serum albumin (BSA) and PSA-alpha 1-antichymotrypsin complex (PSA-ACT) from the preparation. More than 90% of the PSA from LNCaP cell cultures are fPSA. Like fPSA from seminal plasma, two fractions of fPSA differing in protease activity can be separated by DEAE-Sepharose chromatography. Based on the band pattern exhibited on the Western blot following sodium dodecyl sulfate-polyacrylamide electrophoresis separation, fPSA from LNCaP contains more inactive PSA isoforms. This was confirmed by chromatofocusing: the isoelectric point (pl) of the major PSA isoforms from the LNCaP cell culture were higher (6.8 and 6.6) than that (6.4 and 6.1) of fPSA from seminal fluid. We conclude that the LNCaP cell culture is a reliable source for obtaining large quantities of pure fPSA both for the preparation of assay calibrators and controls and for studying the difference in fPSA between benign prostate disease and prostate cancer.
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PMID:Production of milligram concentrations of free prostate specific antigen (fPSA) from LNCaP cell culture: difference between fPSA from LNCaP cell and seminal plasma. 948 63

Serial prostate-specific antigen (PSA) measurements (PSA velocity) as an additional instrument to detect prostatic cancer was introduced in 1992. It has previously been reported that PSA increase per year differed in the last 5 years prior to diagnosis in patients with benign prostatic hyperplasia (0.18 ng/ml/year), locally confined (0.75 ng/ml/year) and metastasized (4.4 ng/ml/year) cancer of the prostate (CaP) in contrast to healthy men (0.04 ng/ml/year). The ability of PSA velocity to detect organ-confined CaP in patients with intermediate PSA serum values depends therefore on a reliable and reproducible PSA result. The present study comprised 85 men with PSA values between 3 and 8 ng/ml (Abbott IMx). PSA measurements were repeated with Abbott IMx (n = 85 patients) and Hybritech Tandem-E (n = 59 patients) assays. The PSA serum values differed from one examination to the other from 0.02 to 2.74 ng/ml with the Abbott IMx. Standard deviation amounted to 0.35 ng/ml with the Abbott IMx PSA assay. Using the Hybritech Tandem-E assay, mean standard deviation was 1.15 ng/ml and therefore higher than with the Abbott IMx assay. The difference from one test to the other ranged from 0.05 to 4.05 ng/ml with the Hybritech Tandem-E. Using the Abbott IMx assay, 10.6% of all repeat measurements exceeded 1 ng/ml whereas in the Hybritech Tandem-E assay 62.7% of the second measurements differed > 1 ng/ml from the first PSA result. An increase in PSA serum values may therefore be due to intratest variation, physiological day-to-day variation as well as prostatic disease. It is important to notice that the intra-assay variation may be greater than the PSA increase per year in a patient with CaP. Therefore, PSA velocity seems to be of limited value.
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PMID:Diagnostic significance of prostate-specific antigen velocity at intermediate PSA serum levels in relation to the standard deviation of different test systems. 951 17

PSA (Prostate Specific Antigen) has modified the management of prostatic disease. Changes of PSA levels can be observed in many clinical circumstances other than cancer (endoscopic procedures, prostatitis, medications, etc.). Various methods have been proposed to increase the specificity of PSA in prostatic cancer, particularly when the PSA level is between 4 and 10 ng/ml: age-related PSA, PSA density, PSA velocity, freePSA. These methods allow more refined indications for transrectal biopsies of the prostate which provide the histological evidence essential for the diagnosis of cancer.
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PMID:[Prostatic specific antigen in practice in 1997]. 959 34


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