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Hinyokika Kiyo. Acta Urologica Japonica Apr 1998The development of increasingly specific diagnostic assays has allowed the detection of various forms of prostate-specific antigen (PSA). It has been found that the... (Review)
Review
The development of increasingly specific diagnostic assays has allowed the detection of various forms of prostate-specific antigen (PSA). It has been found that the proportion of free to total PSA (percent free PSA) is significantly lower in men with prostate cancer than in those with other benign diseases. In order to distinguish early, curable prostate cancer from benign prostatic hyperplasia (BPH), percent free PSA measurement is most useful when the total PSA value is 3-10 ng/ml. The measurement of the proportions of these different forms of PSA, i.e., percent free PSA, may constitute an important diagnostic tool, able to differentiate between benign and malignant prostatic disease with increased specificity, reducing false-positive results and, therefore, improve patient prognosis.
Topics: Biopsy; Humans; Male; Prostate; Prostate-Specific Antigen; Prostatic Hyperplasia; Prostatic Neoplasms
PubMed: 9617617
DOI: No ID Found -
The Journal of Urology Nov 1994In conclusion, PSA is the first prostate specific serum marker of clinical usefulness in urology. It represents a valuable clinical tool that has improved our ability to... (Review)
Review
In conclusion, PSA is the first prostate specific serum marker of clinical usefulness in urology. It represents a valuable clinical tool that has improved our ability to detect early prostate cancer and to monitor response to therapy. While large PSA screening studies have demonstrated an appreciable increase in the detection of organ confined, potentially curable prostate cancers, no study to date has yet demonstrated that the increased detection rate will decrease the prostate cancer-specific mortality rate. Yet more importantly, no study to date has demonstrated that early diagnosis using PSA will not decrease the prostate cancer specific mortality rate and until such data exist, PSA should be used to aid in early diagnosis and treatment planning for men with prostate cancer. PSA, when combined with other variables such as Gleason score and clinical stage, improves the prediction of pathological stage for prostate cancer. The introduction of PSA velocity and age specific reference ranges should further enhance the clinical usefulness of PSA. New advances in PSA research hold great promise for further improvements in PSA, and truly make it the most important and useful tumor marker for adenocarcinoma of the prostate.
Topics: Adenocarcinoma; Age Factors; Aged; Humans; Male; Middle Aged; Neoplasm Staging; Prostate-Specific Antigen; Prostatic Neoplasms; Reference Values
PubMed: 7523702
DOI: 10.1016/s0022-5347(17)32422-9 -
The Journal of Urology May 2009Nonsteroidal anti-inflammatory drugs such as aspirin prevent cardiovascular disease and several prior studies suggest that nonsteroidal anti-inflammatory drugs also... (Comparative Study)
Comparative Study
PURPOSE
Nonsteroidal anti-inflammatory drugs such as aspirin prevent cardiovascular disease and several prior studies suggest that nonsteroidal anti-inflammatory drugs also decrease prostate inflammation and prostate cancer risk. We investigated the association between nonsteroidal anti-inflammatory drug use, prostate specific antigen and prostate volume, hypothesizing that there would be lower prostate specific antigen and prostate volume with nonsteroidal anti-inflammatory drug use.
MATERIALS AND METHODS
The Nashville Men's Health Study uses a multicenter, rapid recruitment protocol to collect clinical, biological, behavioral and body measurement data on 1,277 men older than 40 years who are scheduled for diagnostic prostate biopsy. Nonsteroidal anti-inflammatory drug use was ascertained by survey and clinical interview. Medical charts were reviewed to ascertain current prostate specific antigen, prostate volume and clinical diagnoses following biopsy.
RESULTS
Approximately 46% of patients reported receiving nonsteroidal anti-inflammatory drugs, primarily aspirin (37%). After adjusting for age, race and other factors prostate volume was similar between aspirin users and nonusers (47.6 vs 46.0 ml, p = 0.16). In contrast, prostate specific antigen was significantly lower in aspirin users (7.3 vs 8.0 ng/ml, p = 0.01). The association between prostate specific antigen and aspirin was significant in men with latent prostate cancer (6.1 vs 7.3 ng/ml, p <0.01), marginal in patients with high grade prostatic intraepithelial neoplasia (5.0 vs 5.9 ng/ml, p = 0.09) and nonsignificant in those with a negative biopsy (5.6 vs 5.7 ng/ml, p = 0.64). The strongest prostate specific antigen-aspirin association was in men with cancer and a prostate volume of 60 ml or more (7.3 vs 12.7 ng/ml, p <0.01).
CONCLUSIONS
Prostate specific antigen was significantly lower in aspirin users with latent cancer. Prostate volume was not associated with nonsteroidal anti-inflammatory drug use. Results suggest that aspirin may affect prostate cancer detection, suggesting a potential detection bias to address in future studies of nonsteroidal anti-inflammatory drugs and prostate cancer prevention.
Topics: Adult; Age Factors; Aged; Aged, 80 and over; Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Biopsy, Needle; Follow-Up Studies; Humans; Immunohistochemistry; Male; Middle Aged; Neoplasm Staging; Probability; Prostate-Specific Antigen; Prostatic Neoplasms; Reference Values; Retrospective Studies; Sensitivity and Specificity; Tumor Burden
PubMed: 19286210
DOI: 10.1016/j.juro.2009.01.031 -
Chinese Medical Journal Dec 2017The optimal management strategy for prostate cancer (PCa) remains controversial. We performed a systemic review of current progress and controversies regarding the... (Review)
Review
OBJECTIVE
The optimal management strategy for prostate cancer (PCa) remains controversial. We performed a systemic review of current progress and controversies regarding the diagnosis and treatment of PCa.
DATA SOURCES
We searched PubMed for recently published articles up to July 2017 using the following key words: "prostate cancer," "progress," "controversy," "immunotherapy," and "prevention."
STUDY SELECTION
Articles were obtained and reviewed to provide a systematic review of the current progress and controversies regarding PCa management.
RESULTS
The value of serum prostate-specific antigen (PSA) screening remains controversial, but PSA screening is recommended to facilitate the early diagnosis of PCa in high-risk groups. Prostate biopsy via the transrectal or perineal approach has both advantages and disadvantages. There was a significant correlation between testosterone levels and PCa prognosis. The current research is focused on the mechanisms responsible for PCa. Active surveillance has been proposed as a management strategy for low-risk, localized PCa, but there is an urgent need for further clinical studies to establish the criteria for recommending this approach. The main complications of radical resection for PCa are urinary incontinence and erectile dysfunction, though three-dimensional laparoscopic and robot-assisted laparoscopic techniques have obvious advantages over radical surgery. Radiotherapy is also a therapeutic option for PCa, while immunotherapies may alter the prostate tumor microenvironment. Ongoing studies aim to provide guidance on effective sequential and combination strategies. Prevention remains an important strategy for reducing PCa morbidity and mortality.
CONCLUSIONS
The diagnosis, treatment, and prevention of PCa are complex issues, worthy of intensive study. Further studies are needed to improve the management of PCa.
Topics: Humans; Male; Prostate-Specific Antigen; Prostatic Neoplasms; Radiotherapy
PubMed: 29237932
DOI: 10.4103/0366-6999.220317 -
PloS One 2014Prostate-specific antigen (PSA), an enzyme of 30 kDa grouped in the kallikrein family is synthesized to high levels by normal and malignant prostate epithelial cells....
Prostate-specific antigen (PSA), an enzyme of 30 kDa grouped in the kallikrein family is synthesized to high levels by normal and malignant prostate epithelial cells. Therefore, it is the main biomarker currently used for early diagnosis of prostate cancer. Here, presteady-state and steady-state kinetics of the PSA-catalyzed hydrolysis of the fluorogenic substrate Mu-His-Ser-Ser-Lys-Leu-Gln-AMC (spanning from pH 6.5 to pH 9.0, at 37.0°C) are reported. Steady-state kinetics display at every pH value a peculiar feature, represented by an initial "burst" phase of the fluorescence signal before steady-state conditions are taking place. This behavior, which has been already observed in other members of the kallikrein family, suggests the occurrence of a proteolytic mechanism wherefore the acylation step is faster than the deacylation process. This feature allows to detect the acyl intermediate, where the newly formed C-terminal carboxylic acid of the cleaved substrate forms an ester bond with the -OH group of the Ser195 catalytic residue, whereas the AMC product has been already released. Therefore, the pH-dependence of the two enzymatic steps (i.e., acylation and deacylation) has been separately characterized, allowing the determination of pKa values. On this basis, possible residues are tentatively identified in PSA, which might regulate these two steps by interacting with the two portions of the substrate.
Topics: Amino Acid Sequence; Biocatalysis; Humans; Male; Molecular Sequence Data; Prostate-Specific Antigen; Sequence Homology, Amino Acid
PubMed: 25068395
DOI: 10.1371/journal.pone.0102470 -
African Journal of Primary Health Care... Dec 2022Benign prostatic hyperplasia (BPH) is the most common cause of bladder outlet obstruction in men over the age of 50 years. An association between the prostate specific...
BACKGROUND
Benign prostatic hyperplasia (BPH) is the most common cause of bladder outlet obstruction in men over the age of 50 years. An association between the prostate specific antigen (PSA), International Prostate Symptoms Score (IPSS) and prostate volume (PV) may be instrumental in determining patients who may benefit from treatment. Targeted therapy will reduce the cost of care because it is unwise to treat all men with prostate enlargement to prevent complications when the risk of occurrence is negligible.
AIM
To determine the correlation between the PSA, IPSS and PV in men of African descent.
SETTING
This was a cross sectional analysis involving 92 patients diagnosed as having symptomatic BPH at the Ho Teaching Hospital.
METHODS
The data were collected using standardised questionnaires. The IPSS determined urinary symptom severity. The PV was determined using a transabdominal ultrasound machine. Serum PSA was retrieved from the electronic medical records.
RESULTS
The mean PV was 61.04 cm3 ± 21.95 cm3, the mean PSA was 4.21 ng/mL ± 3.85 ng/mL, and mean IPSS of 21.59 ± 3.78. The Pearson's correlation between PV and PSA was 0.283 (p = 0.01), between PV and IPSS was 0.108 (p = 0.30), and finally, between Serum PSA and IPSS Score was -0.086 (p = 0.42).
CONCLUSION
This study showed that serum PSA has a positive correlation with PV. However, IPSS had no significant association with PSA or PV in patients with BPH.Contribution: This study provides insights into the implications of clinical parameters on the management of prostate enlargement.
Topics: Male; Humans; Middle Aged; Prostatic Hyperplasia; Prostate-Specific Antigen; Prostate; Cross-Sectional Studies
PubMed: 36546488
DOI: 10.4102/phcfm.v14i1.3736 -
Asian Pacific Journal of Cancer... 2011Prostate cancer is the most common malignancy and the second leading cause of cancer related deaths among men in many countries. Serum levels of prostate-spesific...
Prostate cancer is the most common malignancy and the second leading cause of cancer related deaths among men in many countries. Serum levels of prostate-spesific antigen (PSA) have attracted attention for prediction purposes. The methylenetetrahydrofolate reductase (MTHFR) gene play a critical role in cancer development, but its potential impact on prostate cancer has not been well studied. The C677T variant lies in exon 4 at the folate binding site of the MTHFR gene and results in substitution of an alanine by a valine residue. The present study was carried out 55 cases with prostate cancer and 50 healthy men. Polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and agarose gel electrophoresis techniques were employed to determine MTHFR C677T mutation. The frequencies of the CT genotype (p= 0.025) and T allele (p= 0.023) was found to be higher in control subjects when compared with patients group. No statistical difference was found between the alleles of MTHFR and PSA levels after (PSA-BT)/ before (PSA-AT) antiandrogen treatment or tumor stages. We suggest that the heterozygote CT genotype and the 677T allele of the MTHFR polymorphism might be associated with an decreased prostate cancer risk.
Topics: Aged; Alleles; Binding Sites; Exons; Folic Acid; Genetic Predisposition to Disease; Genotype; Humans; Male; Methylenetetrahydrofolate Reductase (NADPH2); Polymorphism, Genetic; Prostate-Specific Antigen; Prostatic Neoplasms
PubMed: 22296369
DOI: No ID Found -
Annals of Medicine Jun 1994Prostate-specific antigen (PSA) is a 33 kD protein synthesized in the epithelial cells of the prostate gland. It is a serine protease that belongs to the subgroup of... (Review)
Review
Prostate-specific antigen (PSA) is a 33 kD protein synthesized in the epithelial cells of the prostate gland. It is a serine protease that belongs to the subgroup of kallikreins, among which it is very similar to a putative enzyme called human glandular kallikrein (hGK-1). Although the hGK-1 enzyme remains to be characterized in vivo, the hGK-1 gene is expressed in the same prostatic epithelial cells as the PSA gene. Expression of the PSA gene is under complex control and the steady-state level of PSA mRNA is increased by androgens, and decreased by epidermal growth factor and activation of protein kinase C. This suggests the existence of several regulatory elements within the cis-acting control elements of the PSA gene. As a seminal serine protease, PSA has been shown to digest the high molecular weight seminal vesicle protein, seminogelin. However, it is likely that this does not constitute the only natural substrate of PSA, as PSA has been shown to degrade insulin-like growth factor-binding protein-3. Serum PSA concentrations are frequently increased in patients with prostatic cancer, but this is also the case in patients with benign prostatic hyperplasia. Thus, PSA measurements alone are not useful as a screening tool for undiagnosed prostatic cancer. However, serum PSA concentrations can be successfully used together with other methods in diagnosing prostatic diseases and in monitoring the successfulness of treatments for prostatic cancer.
Topics: Biomarkers, Tumor; Gene Expression Regulation; Humans; Kallikreins; Male; Prostate; Prostate-Specific Antigen; Prostatic Neoplasms; Structure-Activity Relationship; Tissue Kallikreins
PubMed: 7521173
DOI: 10.3109/07853899409147884 -
The Journal of Urology Jun 1997The ratio of free-to-total prostate specific antigen (PSA) in serum is greater in patients with benign prostatic hyperplasia (BPH) than in those with prostate cancer,...
PURPOSE
The ratio of free-to-total prostate specific antigen (PSA) in serum is greater in patients with benign prostatic hyperplasia (BPH) than in those with prostate cancer, and it provides a means of partially discriminating these 2 diseases. To understand the molecular mechanism of why the free-to-total PSA ratio is greater in BPH than in prostate cancer we analyzed PSA obtained directly from nodules of BPH tissue.
MATERIALS AND METHODS
PSA from BPH nodule fluids was first purified by gel filtration and ion exchange chromatography. Purified BPH PSA was characterized by gel electrophoresis, enzyme assay and N-terminal sequence analysis of the amino acids.
RESULTS
A single band at 30 kDa. on sodium dodecyl sulfate polyacrylamide gel electrophoresis under nonreducing conditions was identical to that of seminal fluid PSA. Under reducing conditions most BPH PSA was degraded, whereas most seminal fluid PSA existed as an intact molecule. BPH PSA had multiple internal cleavages in addition to the common cleavage site between lysines 145 and 146 of seminal fluid PSA. Cleavage sites at C-terminals of histidine 54 and phenylalanine 57 were also detected. Enzymatic activity studies with different substrates showed that PSA from seminal fluid and BPH nodules had similar specific trypsin-like activity. However, BPH PSA had much lower specific chymotrypsin-like activity than seminal fluid PSA. N-terminal sequence analysis showed that BPH PSA was neither in the pre-proenzyme form (261 amino acids) nor the zymogen proenzyme form (244 amino acids) of PSA, both of which are known precursors of mature PSA (237 amino acids).
CONCLUSIONS
Most PSA in BPH nodules is in the nicked form with low chymotrypsin-like activity. When it leaks into the circulation it will form fewer PSA-antichymotrypsin complexes and more will remain in the free form. We predict that a protease with trypsin-like activity in BPH nodule fluid is probably responsible for the nicked form of BPH PSA. These findings suggest that antibodies produced against PSA in BPH nodules may be useful in discriminating prostate cancer from BPH.
Topics: Humans; Male; Prostate; Prostate-Specific Antigen; Prostatic Hyperplasia; Sequence Analysis
PubMed: 9146608
DOI: No ID Found -
Value in Health Regional Issues May 2020To analyze the cost-effectiveness of prostate cancer screening among Chinese men.
OBJECTIVES
To analyze the cost-effectiveness of prostate cancer screening among Chinese men.
METHODS
A cost-effectiveness analysis was performed from a societal perspective using a Markov model to compare 2 strategies: the population-based screening strategy and the current clinical diagnostic strategy. Relevant parameters were retrieved from published literature data and surveys, and univariate sensitivity analysis was used to assess the robustness of the model. We simulated the health outcomes for the next 25 years for 100 000 men and calculated the incremental cost-effectiveness ratio (ICER).
RESULTS
This study found that the population-based screening strategy, compared with the clinical diagnostic strategy, could save 756.61 quality-adjusted life-years (QALYs) for the hypothetical population. The ICER for the population-based screening strategy was ¥14 747.11/QALY, and this value was less than the willingness-to-pay threshold of ¥64 520. With life-year gains (LYGs) as the model output, the population-based screening strategy yielded an ICER of ¥16 470.45/LYG. The univariate sensitivity analyses showed that the ICER was sensitive to the prostate-specific antigen (PSA) test fee, the proportion diagnosed with low-grade prostate cancer (PC) in the population-based strategy, and the proportion diagnosed with intermediate-grade PC in the population-based strategy.
CONCLUSIONS
Prostate cancer screening based on PSA test results appears to be cost-effective for Chinese men who are in good health and have a life expectancy of more than 10 years. Nevertheless, this finding needs to be further studied with more treatment cost parameters (treatment costs related to impotence and urinary incontinence) and using local utility value information.
Topics: Aged; China; Cost-Benefit Analysis; Early Detection of Cancer; Humans; Male; Markov Chains; Middle Aged; Prostate-Specific Antigen; Prostatic Neoplasms; Quality-Adjusted Life Years
PubMed: 32402819
DOI: 10.1016/j.vhri.2020.01.005