Regulatory requirements on PSA level 2: Review, aspects and applications

International Nuclear Information System (INIS)

Husarcek, J.

2003-01-01

The general requirements concerning utility obligations, probabilistic safety criteria (CDF should not exceed 1.0E-4/reactor year and LERF should not exceed 1.0E-5/reactor year), documentation and results, living PSA requirements and major steps in level 2 PSA are presented. PSA developments in Slovakia, collection and assembly of information, plant damage states, containment performance and failure modes, severe accident progression analyses, containment failure modes and source terms as a part of performed level 2 PSA are discussed. The PSA applications in design and operation evaluation, support to plant upgrade and modifications are also described. At the end, the following conclusion is made: more extensive PSA application needs to foster the exchange of experience and communication between PSA specialists, non-PSA engineers, designers, and the regulatory body staff responsible for safety assessment, inspection and enforcement

ASAMPSA-E guidance for level 2 PSA Volume 2. Implementing external Events modelling in Level 2 PSA

International Nuclear Information System (INIS)

Cazzoli, E.; Vitazkova, J.; Loeffler, H.; Burgazzi, L.

2016-01-01

The objective of the present document is to provide guidance on the implementation of external events into an 'extended' L2 PSA. It has to be noted that L2 PSA addresses issues beginning with fuel degradation and ending with the release of radionuclides into the environment. Therefore, the present document may touch upon, but does not evaluate explicitly issues that involve events or phenomena which occur before the fuel begins to degrade. Following the accident at Fukushima Dai-ichi, the nuclear safety community has realized that much attention should be given to the areas of operator interventions and accidents that may develop at the same time in more than one unit if they are initiated by one or more common external events. For this reason and to fulfill the PSA end-users' wish list (as reflected by an ASAMPSA-E survey), the attention is mostly focused on interface between L1 and L2 PSA, fragility analysis, human response analysis and some consideration is given to L2 PSA modeling of severe accidents for multiple unit sites, even though it is premature to provide extensive guidance in this area. The following recommendations, mentioned in various sections within this document, are summarized here: 1. Vulnerability/fragility analyses should be performed with respect to all external hazards and all structures, systems and components potentially affected that could be relevant to L2 PSA, 2. Importance should be given to the assessment of human performance following extreme external events; for extreme circumstances with high stress level, low confidence is justified for SAM human interventions and for such conditions, human interventions could be analyzed as sensitivity cases only in L2 PSA, 3. Results presentation should include assessment of total risk measures compared with risk targets able to assess all contributions to the risk and to judge properly the safety, 4. Total risk measures shall be associated to appropriate information on all

Investigation of the efficiency and qualification of computer codes for PSA

International Nuclear Information System (INIS)

Andernacht, M.; Dinsmore, S.

1992-01-01

An international selection of computer codes for the quantification of level 1 PSA models was evaluated due to the consistence of results of different Benchmark exercises. The exercises in this project are based on those developed during the first benchmark project (Phase I). Due to several large differences in the results during Phase I of the Benchmark, the exercises in Phase II were more precisely defined. Due to the improved definition of the benchmark exercises, the results delivered from the different computer codes for Phase II are much more consistent. In general, the results of Benchmark II show, that the exercises were defined well enough to allow consistant results to be generated. Thus, the exercises can also be used to support the evaluation of additional PSA programs. (orig.) [de

PSA levels as a predictor of 68Ga PSMA PET/CT positivity in patients with prostate cancer?

Science.gov (United States)

Soydal, Cigdem; Urun, Yuksel; Suer, Evren; Nak, Demet; Ozkan, Elgin; Kucuk, Ozlem N

2018-05-10

The aim of this study is to evaluate predictive factors of 68Gallium (68Ga) Prostate-Specific Membrane Antigen (PSMA) Positron Emission Tomography (PET)/Computed Tomography (CT) positivity. Relationships between serum Prostate Specific Antigen (PSA), Lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) levels, Gleason Score (GS) and positivity of 68Ga PSMA PET in patients who underwent 68Ga PSMA PET/CT for restaging for PCa were evaluated retrospectively. One hundred and four (median age: 67; range: 51-88) patients were included in this study. Of these patients, PSMA PET was positive in 75 (72%) patients. Mean serum PSA levels for PET negative and positive groups were 0.76±1.00 and 180.85±324.93 ng/ml (pPSA cut-off and 92% and 90%, respectively, for the 2 ng/ml PSA cut-off values. The positivity rates for patients with PSA levels PSA recurrence. Patients with higher GS and early PSA recurrence could benefit from 68Ga PSMA PET/CT.

PSA LEVEL 3 DAN IMPLEMENTASINYA PADA KAJIAN KESELAMATAN PWR

Directory of Open Access Journals (Sweden)

Pande Made Udiyani

2015-03-01

Full Text Available Kajian keselamatan PLTN menggunakan metodologi kajian probabilistik sangat penting selain kajian deterministik. Metodologi kajian menggunakan Probabilistic Safety Assessment (PSA Level 3 diperlukan terutama untuk estimasi kecelakaan parah atau kecelakaan luar dasar desain PLTN. Metode ini banyak dilakukan setelah kejadian kecelakaan Fukushima. Dalam penelitian ini dilakukan implementasi PSA Level 3 pada kajian keselamatan PWR, postulasi kecelakan luar dasar desain PWR AP-1000 dan disimulasikan di contoh tapak Bangka Barat. Rangkaian perhitungan yang dilakukan adalah: menghitung suku sumber dari kegagalan teras yang terjadi, pemodelan kondisi meteorologi tapak dan lingkungan, pemodelan jalur paparan, analisis dispersi radionuklida dan transportasi fenomena di lingkungan, analisis deposisi radionuklida, analisis dosis radiasi, analisis perlindungan & mitigasi, dan analisis risiko. Kajian menggunakan rangkaian subsistem pada perangkat lunak PC Cosyma. Hasil penelitian membuktikan bahwa implementasi metode kajian keselamatan PSA Level 3 sangat efektif dan komprehensif terhadap estimasi dampak, konsekuensi, risiko, kesiapsiagaan kedaruratan nuklir (nuclear emergency preparedness, dan manajemen kecelakaan reaktor terutama untuk kecelakaan parah atau kecelakaan luar dasar desain PLTN. Hasil kajian dapat digunakan sebagai umpan balik untuk kajian keselamatan PSA Level 1 dan PSA Level 2. Kata kunci: PSA level 3, kecelakaan, PWR   Reactor safety assessment of nuclear power plants using probabilistic assessment methodology is most important in addition to the deterministic assessment. The methodology of Level 3 Probabilistic Safety Assessment (PSA is especially required to estimate severe accident or beyond design basis accidents of nuclear power plants. This method is carried out after the Fukushima accident. In this research, the postulations beyond design basis accidentsof PWR AP - 1000 would be taken, and simulated at West Bangka sample site. The

Guideline level-3 PSA

International Nuclear Information System (INIS)

Roelofsen, P.M.; Van der Steen, J.

1993-09-01

For several applications of radioactive materials calculations must be executed to determine the radiation risk for the population. A guideline for the risk calculation method of two main sources: nuclear power plants, and other intended and unintended activities with radioactive materials, is given. The standards, recommendations and regulations in this report concern mainly the analysis of the radiological (external) consequences of nuclear power plant accidents, classified as level-3 PSA (Probabilistic Safety Analysis). Level-3 PSA falls within the scales 5-7 of the International Nuclear Event Scale (INES). The standards, etc., focus on the risks for groups of people and the so-called maximum individual risk. In chapter two the standards and regulations are formulated for each part of level-3 PSA: the source term spectrum, atmospheric distribution and deposition, exposure to radiation doses and calculation of radiation doses, dose-response relationships, measures to reduce the effect of radiation doses, design basis accidents, and finally uncertainty analysis. In chapter four, modelled descriptions are given of the standards and regulations, which could or should be used in a calculation program in case of level-3 PSA. In chapter three the practical execution of a probabilistic consequences analysis, the collection of input data and the presentation of the results are dealt with. 2 figs., 14 tabs., 64 refs

Regulatory review of probabilistic safety assessment (PSA) Level 2

International Nuclear Information System (INIS)

2001-07-01

Probabilistic safety assessment (PSA) is increasingly being used as part of the decision making process to assess the level of safety of nuclear power plants. The methodologies in use are maturing and the insights gained from the PSAs are being used along with those from deterministic analysis. Many regulatory authorities consider the current state of the art in PSA to be sufficiently well developed for results to be used centrally in the regulatory decision making process-referred to as risk informed regulation. For these applications to be successful, it will be necessary for the regulatory authority to have a high degree of confidence in the PSA. However, at the 1994 IAEA Technical Committee Meeting on Use of PSA in the Regulatory Process and at the OECD Nuclear Energy Agency Committee for Nuclear Regulatory Activities (CNRA) 'Special Issues' meeting in 1997 on Review Procedures and Criteria for Different Regulatory Applications of PSA, it was recognized that formal regulatory review guidance for PSA did not exist. The senior regulators noted that there was a need to produce some international guidance for reviewing PSAs to establish an agreed basis for assessing whether important technological and methodological issues in PSAs are treated adequately and to verify that conclusions reached are appropriate. In 1997, the IAEA and OECD Nuclear Energy Agency agreed to produce, in cooperation, guidance on Regulatory Review of PSA. This led to the publication of IAEA-TECDOC-1135 on the Regulatory Review of Probabilistic Safety Assessment (PSA) Level 1, which gives advice for the review of Level 1 PSA for initiating events occurring at power plants. This TECDOC extends the coverage to address the regulatory review of Level 2 PSA.These publications are intended to provide guidance to regulatory authorities on how to review the PSA for a nuclear power plant to gain confidence that it has been carried out to an acceptable level of quality so that it can be used as the

Benchmark exercises on PWR level-1 PSA (step 3). Analyses of accident sequence and conclusions

International Nuclear Information System (INIS)

Niwa, Yuji; Takahashi, Hideaki.

1996-01-01

The results of level 1 PSA generate fluctuations due to the assumptions based on several engineering judgements set in the stages of PSA analysis. On the purpose of the investigation of uncertainties due to assumptions, three kinds of a standard problem, what we call benchmark exercise have been set. In this report, sensitivity studies (benchmark exercise) of sequence analyses are treated and conclusions are mentioned. The treatment of inter-system dependency would generate uncertainly of PSA. In addition, as a conclusion of the PSA benchmark exercise, several findings in the sequence analysis together with previous benchmark analyses in earlier INSS Journals are treated. (author)

Computer codes for level 1 probabilistic safety assessment

International Nuclear Information System (INIS)

1990-06-01

Probabilistic Safety Assessment (PSA) entails several laborious tasks suitable for computer codes assistance. This guide identifies these tasks, presents guidelines for selecting and utilizing computer codes in the conduct of the PSA tasks and for the use of PSA results in safety management and provides information on available codes suggested or applied in performing PSA in nuclear power plants. The guidance is intended for use by nuclear power plant system engineers, safety and operating personnel, and regulators. Large efforts are made today to provide PC-based software systems and PSA processed information in a way to enable their use as a safety management tool by the nuclear power plant overall management. Guidelines on the characteristics of software needed for management to prepare a software that meets their specific needs are also provided. Most of these computer codes are also applicable for PSA of other industrial facilities. The scope of this document is limited to computer codes used for the treatment of internal events. It does not address other codes available mainly for the analysis of external events (e.g. seismic analysis) flood and fire analysis. Codes discussed in the document are those used for probabilistic rather than for phenomenological modelling. It should be also appreciated that these guidelines are not intended to lead the user to selection of one specific code. They provide simply criteria for the selection. Refs and tabs

Level 1 and 2 PSA methodology taking into account new design, operating and safety factors. Rev. 1

International Nuclear Information System (INIS)

Jirsa, P.; Patrik, M.

2000-11-01

The status of probabilistic safety assessment (PSA) is discussed (i) in relation to the expected nature of 'revolutionary' innovations and (ii) in the light of the EUR document, summarizing requirements put by European NPP operators on the future NPP design. The aims included: (1) analysis of limitations to the current PSA methodology; (2) specification of physical and operation processes the knowledge of which is necessary to ensure the safety criteria of advanced reactors; (3) summarisation of existing knowledge and description formats of the processes; (4) identification of theoretical and experimental work required to address the problem, preparation of data and computer codes, ensuring traceability to EU developmental programs. (P.A.)

A formal treatment of uncertainty sources in a level 2 PSA

International Nuclear Information System (INIS)

Ahn, Kwang Il; Yang, Joon Eon

2003-01-01

The methodological framework of the level 2 PSA appears to be currently standardized in a formalized fashion, but there have been different opinions on the way the sources of uncertainty are characterized and treated. This is primarily because the level 2 PSA deals with complex phenomenological processes that are deterministic in nature rather than random processes, and there are no probabilistic models characterizing them clearly. As a result, the probabilistic quantification of the level 2 PSA is often subjected to two sources of uncertainty: (a) incomplete modeling of accident pathways or different predictions for the behavior of phenomenological events and (b) expert-to-expert variation in estimating the occurrence probability of phenomenological events. While a clear definition of the two sources of uncertainty involved in the level 2 PSA makes it possible to treat an uncertainty in a consistent manner, careless application of these different sources of uncertainty may produce different conclusions in the decision-making process. The primary purpose of this paper is to characterize typical sources of uncertainty that would often be addressed in the level 2 PSA and their impacts on the PSA level 2 risk results. An additional purpose of this paper is to give a formal approach on how to combine random uncertainties addressed in the level 1 PSA with subjectivistic uncertainties addressed in the level 2 PSA

Post treatment PSA nadirs support continuing dose escalation study in patients with pretreatment PSA levels >10 ng/ml, but not in those with PSA <10 NG/ML

International Nuclear Information System (INIS)

Herold, D.H.; Hanlon, A.L.; Movsas, B.; Hanks, G.E.

1996-01-01

Purpose: We have recently shown that ICRU reporting point radiation doses above 71 Gy are not associated with improved bNED survival in prostate cancer patients with pretreatment PSA level 20 ng/ml we found a strong correlation between dose and nadir values < 1.0 ng/ml (p=.003) as well as for nadir's < 0.5 ng/ml (p=.04). This dose/nadir effect held at several dose levels, but 74 Gy for nadir values < 1.0 ng/ml and 72 Gy for nadir's < 0.5 ng/ml remained the most significant. 32% of these patients achieved a nadir < 1.0ng/ml and 15% < 0.5ng/ml. Conclusions: This analysis provides strong additional support that patients with pretreatment PSA values of < 10 ng/ml do not benefit from dose escalation beyond an ICRU reporting point dose of 71 Gy. For patients with pretreatment PSA's of 10-19.9 ng/ml there is no dose/nadir response evaluated at a nadir of 1.0 ng/ml; however, there is a borderline effect observed at a nadir of 0.5 ng/ml. Patients with pretreatment PSA's of 20 ng/ml or greater clearly benefit from higher doses as evaluated by PSA nadirs of 1.0 ng/ml, and 0.5 ng/ml. These studies support the continued investigation of dose escalation in treating patients with PSA levels over 10 ng/ml, they do not support continued investigation of dose escalation beyond 71 Gy in patients with pretreatment PSA levels < 10 ng/ml. The failure to demonstrate any dose response for the low PSA group and the finding of only a borderline effect for the intermediate PSA group may be influenced by the relatively small number of patients in our series treated to doses < 70 Gy and the fact that none of our patients were treated to doses below 65.98 Gy. The lower limit of acceptible dose has yet to be defined

Clinical significance of combined determination of serum levels of free prostate specific antigen (fPSA) and insulin-like growth factor-1 (IGF-1) in patients with prostatic cancer

International Nuclear Information System (INIS)

Wang Xiaolong; Chen Baixun; Chen Yue

2004-01-01

Objective: To explore the clinical significance of combined determination of serum levels of fPSA and IGF-1 in patients with prostatic cancer. Methods: Serum levels of fPSA (with chemiluminescence) and IGF-1 (with IRMA) were measured in 48 patients with prostatic cancer, 63 patients with benign prostate hyperplasia and 38 controls. Results: Serum levels of fPSA and IGF-1 in the 111 patients were significantly higher than those in controls (P<0.05). The positive rate for prostatic cancer detection with fPSA, IGF-1 and fPSA combined with IGF-1 was 83.3%, 79.2% and 95.8% respectively. Conclusion: Combined measurement of fPSA and IGF-1 was most preferable for screening prostatic cancer

Review process of PSA level 2 of KBR - Concept and Experience

International Nuclear Information System (INIS)

Andernacht, M.; Glaser, H.; Sonnenkalb, M.

2013-01-01

In Germany, a periodic safety review (PSR) has to be performed every ten years by the utility. In the past, a PSR only included a plant-specific probabilistic safety analysis (PSA) Level 1 study. Since a revised version of the German PSA guideline has been released in 2005, these plant-specific PSAs have to include a PSA Level 2, too. For the NPP Brokdorf (KBR) PSA Level 2 project, an agreement was reached between all parties involved that the study will be performed not as a part of the PSR process, but supplementary to it. This paper will focus on conclusions and findings from an ongoing parallel review process of the first full scope PSA Level 2 performed by the utility for KBR, a typical German PWR-1300. The responsible authority 'Ministerium fuer Soziales, Gesundheit, Familie, Jugend und Senioren des Landes Schleswig- Holstein' (MSGF) initiated this parallel review process in agreement with the utility KBR and the E.ON Kernkraft in 2006. The project will be completed soon. Such a review process allows that essential steps of the PSA will be reviewed and commented before the PSA Level 2 will be finished. So the benefit from this parallel review process is a significant enhancement of the quality and completeness of the PSA Level 2 study as the majority of the recommendations given by the review team has been taken over by the utility and the developer of the PSA, the AREVA NP company. Further, a common understanding and agreement will be reached at the end between all parties involved on the major topics of the PSA Level 2 study. The paper is followed by the slides of the presentation. (authors)

Review process of PSA Level 2 of KBR. Concept and experience

International Nuclear Information System (INIS)

Andernacht, Martin; Glaser, Hendrik; Sonnenkalb, Martin

2009-01-01

In Germany, a periodic safety review (PSR) has to be performed every 10 years by the utility. In the past, a PSR only included a plant-specific probabilistic safety analysis (PSA) Level 1 study. For the NPP Brokdorf (KBR) PSA Level 2 project, an agreement was reached between all parties involved that the study will be performed not as a part of the PSR process, but supplementary to it. Since a revised version of the German PSA guideline has been released in 2005, these plant-specific PSAs have to include a PSA Level 2, too. This paper will focus on conclusions and findings from a ongoing parallel review process of the first full scope PSA Level 2 performed by the utility for KBR, a typical German PWR-1300. The responsible authority 'Ministerium fuer Soziales, Gesundheit, Familie, Jugend und Senioren des Landes Schleswig-Holstein (MSGF)' (Ministry of Social Affairs, Health, Family, Youth and Senior Citizens of Schleswig-Holstein) initiated this parallel review process in agreement with the utility KBR and the E.ON Kernkraft in 2006. The project will be completed soon. Such a review process allows that essential steps of the PSA will be reviewed and commented before the PSA Level 2 will be finished. So the benefit from this parallel review process is a significant enhancement of the quality and completeness of the PSA Level 2 study as the majority of the recommendations given by the review team has been taken over by the utility and the developer of the PSA, the Areva NP company. Further, a common understanding and agreement will be reached at the end between all parties involved on the major topics of the PSA Level 2 study. (orig.)

Lessons learned form IRSN review of Flamanville 3 Level PSA

International Nuclear Information System (INIS)

Georgescu, G.; Corenwinder, F.

2012-01-01

In the frame of the construction and licensing of Flamanville 3 NPP the PSA (Probabilistic Safety Assessment)plays an important role for the EPR Project assessment. The PSA was used for early design verification of EPR Reactor, several design improvement being defined based on these PSA insights and following the discussions with the French and German safety authorities. IRSN, as the French Safety Authority (ASN) technical support organization, performs the review of the PSA developed by the plant operator (EDF). The paper presents the main issues regarding the using of 'design PSA', identified by IRSN following the review of the internal events Level 1 PSA transmitted by EDF in the frame of the anticipated instruction of the application for operating license of the Flamanville 3 reactor. (authors)

Summary report of already existing guidance on the implementation of External Hazards in extended Level 1 PSA

International Nuclear Information System (INIS)

Klug, J.; Kumar, M.; Prochaska, J.; Brac, P.; Vasseur, D.; Brinkman, H.; Kahia, S.; Nitoi, Mirela; Apostol, M.; Georgescu, G.; Volkanovski, Andrija; Mustoe, J.; Alzbutas, R.; La Rovere, S.

2015-08-01

The report provides a summary of already existing guidance on the implementation of external hazards in extended level 1 PSA. It summarized the lessons learnt from existing standards, existing gaps and possibility for future development within the work-package WP22 'How to introduce hazards in L1 PSA and all possibilities of events combinations'. The report is focused on the four following areas, for several hazards: 1) Impact on the SSCs modelled in L1 PSA event trees; 2) Impact on Human Reliability Assessment modelling in L1 PSA; 3) Site impact modelling in L1 PSA event trees; 4) Link between external initiating events of PSA and NPP design basis conditions. During the review of existing guidance, it appeared that many of the references form a suitable basis to introduce external hazards in L1 PSA including event combination. Available guidelines provide usable recommendations to evaluate failure probabilities of SSCs depending on the influence of single hazard or events combination. The most detailed guidelines are devoted to the seismic events and fires. Even if these guidelines deal only with single event impact, they can be also used for combined events purpose to evaluate particular effects induced by analyzed external hazards. Guidelines provide general systematic framework how to determine the scope of SSCs for extended PSA and failure modes (develop an extended list of components). In general available guidelines provide detailed framework for analysis of seismic event. The other external hazards are not always covered so deeply. This is probably caused by specific site nature of these hazards like external floods, fires etc. In case of HRA, more detailed information and HRA models are available for seismic events or fire events. For the other external hazards, the literature with regard to HRA is not well developed. The PSA for external hazards should take account the potential for human response to be affected by the external event. More realistic Human

Serum PSA levels in the Indian population: Is it different?

Science.gov (United States)

Agrawal, Amit; Karan, Shailesh Chandra

2017-04-01

Serum prostate-specific antigen (PSA) is an important tumour, marker which is widely used to trigger trans-rectal ultrasound (TRUS)-guided prostate biopsy. However, the PSA levels vary with race and ethnicity. Therefore, there is a need to have an Indian reference range. All adult male patients meeting the inclusion and exclusion criteria were enrolled in this study. They were subjected to assessment of serum total PSA, digital rectal examination and trans-abdominal ultrasound. If any one or more of these were found abnormal, then a TRUS-guided 12-core prostate biopsy was done. Patients who were detected to have prostatic cancer were excluded from the final analysis. The data so obtained was grouped among the following three age groups: 40-49, 50-59 and 60-70 years, and the age-specific PSA values, prostatic volume and PSA density were found. A total of 1772 patients were analysed. The mean serum total PSA was 1.76 ng/ml with a standard deviation of 2.566 ng/ml. Group-wise age distribution of the mean serum total PSA was 1.22, 1.97 and 2.08 ng/ml in 40-49, 50-59 and 60-70 years age groups. The mean total PSA and the age-specific PSA range tend to be lower in the Indians than the Western population.

Methodologies for uncertainty analysis in the level 2 PSA and their implementation procedures

International Nuclear Information System (INIS)

Ahn, Kwang Il; Yang, Joon Eun; Kim, Dong Ha

2002-04-01

Main purpose of this report to present standardized methodologies for uncertainty analysis in the Level 2 Probabilistic Safety Assessment (PSA) and their implementation procedures, based on results obtained through a critical review of the existing methodologies for the analysis of uncertainties employed in the Level 2 PSA, especially Accident Progression Event Tree (APET). Uncertainties employed in the Level 2 PSA, quantitative expressions of overall knowledge of analysts' and experts' participating in the probabilistic quantification process of phenomenological accident progressions ranging from core melt to containment failure, their numerical values are directly related to the degree of confidence that the analyst has that a given phenomenological event or accident process will or will not occur, or analyst's subjective probabilities of occurrence. These results that are obtained from Level 2 PSA uncertainty analysis, become an essential contributor to the plant risk, in addition to the Level 1 PSA and Level 3 PSA uncertainties. Uncertainty analysis methodologies and their implementation procedures presented in this report was prepared based on the following criteria: 'uncertainty quantification process must be logical, scrutable, complete, consistent and in an appropriate level of detail, as mandated by the Level 2 PSA objectives'. For the aforementioned purpose, this report deals mainly with (1) summary of general or Level 2 PSA specific uncertainty analysis methodologies, (2) selection of phenomenological branch events for uncertainty analysis in the APET, methodology for quantification of APET uncertainty inputs and its implementation procedure, (3) statistical propagation of uncertainty inputs through APET and its implementation procedure, and (4) formal procedure for quantification of APET uncertainties and source term categories (STCs) through the Level 2 PSA quantification codes

Final guidance document for extended Level 2 PSA Volume 1. Summary report for external hazards implementation in extended L2 PSA, validation of SAMG strategy and complement of ASAMPSA2 L2PSA guidance

International Nuclear Information System (INIS)

Loeffler, H.; Raimond, E.

2016-01-01

The present document is a summary of the deliverables produced within the ASAMPSA-E project for extended L2 PSA. These deliverables are: D30.7 vol. 2, 'Implementing external Events modelling in Level 2 PSA': D30.7 vol. 3: 'Verification and improvement of SAM strategy: D30.7 vol. 4: 'Consideration of shutdown states, spent fuel pools and recent R and D results'. Among many others, the following summary statements are provided: Analyses of external events: - No need for new methodology, - It is necessary to develop L1 PSA first and then clearly defined boundary conditions for the L2 PSA must be generated, - The remaining challenge is how to address adverse environmental conditions due to external hazards. Multi units: - No practical methodology exists to treat the problem, - A new methodology is necessary to be developed first for the L1 PSA. This should, from the beginning, take into account the specific needs of L2 PSA so that the boundary conditions for subsequent level 2 analysis can be generated adequately. SAM strategies verification and improvement: - L2 PSA methodology can usefully by applied and experience exists for internal initiating events L2 PSA, - How to address adverse environmental conditions due to external hazards - needs for new methodology or examples of experience, - How to model the decision process when there is a conflict of interest - needs for new methodology or examples of experience. For L2 PSA in shutdown states with open RPV, some new technical issues (fission product release, thermal load to structures above RPV) have to be addressed. Spent fuel pool issues have been developed, in particular: - Heat load from the melting spent fuel to structures above (e.g. to the containment roof) is a severe challenge for the plant and for the present-day, methodology is missing. Recent R and D achievements with relevance for L2 PSA: - Basic research has been continued in the radiochemistry (iodine and ruthenium chemistry) field, but the existing

External hazards analysis approach to level 1 PSA of Mochovce NPP - Slovakia

International Nuclear Information System (INIS)

Stojka, Tibor

2000-01-01

Analyses of external events had been first time performed at the design stage of the Mochovce NPP showing sufficiently low contribution of external hazards to core damage frequency. But, based on IAEA document 'Safety problems of WWER-440/213 NPPs and the categorization' (IAEA-EBP-WWER-03, 1996), the need of new reassessment arose due to discrepancy of some origin recommendations in compare with present IAEA ones. Mochovce NPP Nuclear Safety Improvements Program elaborated at the same time included the IAEA recommendations and following improvements were proposed to perform in context of external events. 1. Seismic project and new locality seismic evaluation This safety improvement includes also some 'on site' technical improvements in seismic stability of structures and equipment. 2. Unit specific analyses of extreme meteorologic conditions. This safety improvement focuses on impact of feasible extreme conditions on NPP systems caused by rain, snow and hail storms, frost, winds, low and high temperatures. 3. Analyses of external hazards caused by humans. In this safety improvement were specified: feasible sources of explosions; analyses of hydrogen, gas and propane-calor gas depots; air crash risk. The results of these implemented safety improvements were considered in the PSA study. The External hazards analysis is also part of Level 1 PSA Mochovce NPP performed by PSA Department of VUJE Trnava Inc., Engineering, Design and Research Organization, Slovakia. Some partial analyses are performed in cooperation with following companies DS and S - SAIC, USA and Geophysical Institute Academy of Science, Slovakia Relko, Slovakia. Basic documents are: NUREG/CR-2300 'PRA Procedures Guide - A Guide to the Performance of Probabilistic Risk Assessments for Nuclear Power Plants' and IAEA SS No. 50-P-7 'Treatment of External Hazards in PSA for NPPs. The external hazards analysis consists of following parts: 1. Geography and plant locality; 2. Nearby industry; 3. Extreme

Recent Developments in Level 2 PSA and Severe Accident Management

International Nuclear Information System (INIS)

Ang, Ming Leang; Shepherd, Charles; Gauntt, Randall; Landgren, Vickie; Van Dorsselaere, Jean Pierre; Chaumont, Bernard; Raimond, Emmanuel; Magallon, Daniel; Prior, Robert; Mlady, Ondrej; Khatib-Rahbar, Mohsen; Lajtha, Gabor; Tinkler, Charles; Siu, Nathan

2007-01-01

In 1997, CSNI WGRISK produced a report on the state of the art in Level 2 PSA and severe accident management - NEA/CSNI/R(1997)11. Since then, there have been significant developments in that more Level 2 PSAs have been carried out worldwide for a variety of nuclear power plant designs including some that were not addressed in the original report. In addition, there is now a better understanding of the severe accident phenomena that can occur following core damage and the way that they should be modelled in the PSA. As requested by CSNI in December 2005, the objective of this study was to produce a report that updates the original report and gives an account of the developments that have taken place since 1997. The aim has been to capture the most significant new developments that have occurred rather than to provide a full update of the original report, most of which is still valid. This report is organised using the same structure as the original report as follows: Chapter 2: Summary on state of application, results and insights from recent Level 2 PSAs. Chapter 3: Discussion on key severe accident phenomena and modelling issues, identification of severe accident issues that should be treated in Level 2 PSAs for accident management applications, review of severe accident computer codes and the use of these codes in Level 2 PSAs. Chapter 4: Review of approaches and practices for accident management and SAM, evaluation of actions in Level 2 PSAs. Chapter 5: Review of available Level 2 PSA methodologies, including accident progression event tree / containment event tree development. Chapter 6: Aspects important to quantification, including the use of expert judgement and treatment of uncertainties. Chapter 7: Examples of the use of the results and insights from the Level 2 PSA in the context of an integrated (risk informed) decision making process

Comparison of SKIFS 2004:1 and Tillsynshandbok PSA against the ASME PRA Standard and European requirements on PSA

International Nuclear Information System (INIS)

Hellstroem, Per

2005-04-01

Requirements on PSA for risk informed applications are expressed in different international documents. The ASME PRA standard published in spring 2002 is one such document, PSA requirements are also expressed in the European Utility Requirements (EUR) for new reactors. The Swedish PSA requirements are provided in the Swedish regulators (SKI) statutes SKIFS 2004:1. SKI also has a review handbook for PSA activities (SKI report 2003:48). The review handbook is a support during review of the utilities PSA activities and the PSAs themselves. The review handbook expresses SKIs expectations by providing so called important aspects for both the PSA work and the PSAs, A comparison of SKIFS requirements and the important aspects in the Review handbook, on one side, and the requirements on PSA in EUR and ASME on the other side, is presented. The comparison shows a large difference in the level of detail in the different documents, where ASME is most detailed and specific. This is expected since the SKI review handbook not is a 'PSA guide' in the same way as the ASME PRA standard. A direct comparison of the ASME PRA standard requirements with the important aspects in the review handbook cannot answer the question which ASME capacity level that is achieved by a PSA meeting all important aspects. The conclusion is that it is not likely to achieve capacity level 2 and 3, since very few ASME level 3 attributes are explicitly expressed as important aspects, though many are expressed in general terms. The review handbook important aspects that are most similar to the ASME capacity level 1 attributes are initiating events, sequence analysis, and system analysis while less similarity is found for analysis of operator actions data analysis, quantification and containment analysis (level 2). Less similarity is found for capacity level 2 and 3. However, the number of additional ASME attributes on capacity level 2 and 3 are few. There are also important aspects in the review handbook that

Extent of disease in recurrent prostate cancer determined by [(68)Ga]PSMA-HBED-CC PET/CT in relation to PSA levels, PSA doubling time and Gleason score.

Science.gov (United States)

Verburg, Frederik A; Pfister, David; Heidenreich, Axel; Vogg, Andreas; Drude, Natascha I; Vöö, Stefan; Mottaghy, Felix M; Behrendt, Florian F

2016-03-01

To examine the relationship between the extent of disease determined by [(68)Ga]PSMA-HBED-CC-PET/CT and the important clinical measures prostate-specific antigen (PSA), PSA doubling time (PSAdt) and Gleason score. We retrospectively studied the first 155 patients with recurrent prostate cancer (PCA) referred to our university hospital for [(68)Ga]PSMA-HBED-CC PET/CT. PET/CT was positive in 44%, 79% and 89% of patients with PSA levels of ≤1, 1-2 and ≥2 ng/ml, respectively. Patients with high PSA levels showed higher rates of local prostate tumours (p PSA and PSAdt were independent determinants of scan positivity and of extrapelvic lymph node metastases. PSAdt was the only independent marker of bone metastases (p = 0.001). Of 20 patients with a PSAdt PSA ≥2 ng/ml, 19 (95%) had a positive scan and 12 (60%) had M1a disease. Of 14 patients with PSA 6 months, only 5 (36%) had a positive scan and 1 (7%) had M1a disease. [(68)Ga]PSMA-HBED-CC PET/CT will identify PCA lesions even in patients with very low PSA levels. Higher PSA levels and shorter PSAdt are independently associated with scan positivity and extrapelvic metastases, and can be used for patient selection for [(68)Ga]PSMA-HBED-CC PET/CT.

Multi-Unit Initiating Event Analysis for a Single-Unit Internal Events Level 1 PSA

Energy Technology Data Exchange (ETDEWEB)

Kim, Dong San; Park, Jin Hee; Lim, Ho Gon [KAERI, Daejeon (Korea, Republic of)

2016-05-15

The Fukushima nuclear accident in 2011 highlighted the importance of considering the risks from multi-unit accidents at a site. The ASME/ANS probabilistic risk assessment (PRA) standard also includes some requirements related to multi-unit aspects, one of which (IE-B5) is as follows: 'For multi-unit sites with shared systems, DO NOT SUBSUME multi-unit initiating events if they impact mitigation capability [1].' However, the existing single-unit PSA models do not explicitly consider multi-unit initiating events and hence systems shared by multiple units (e.g., alternate AC diesel generator) are fully credited for the single unit and ignores the need for the shared systems by other units at the same site [2]. This paper describes the results of the multi-unit initiating event (IE) analysis performed as a part of the at-power internal events Level 1 probabilistic safety assessment (PSA) for an OPR1000 single unit ('reference unit'). In this study, a multi-unit initiating event analysis for a single-unit PSA was performed, and using the results, dual-unit LOOP initiating event was added to the existing PSA model for the reference unit (OPR1000 type). Event trees were developed for dual-unit LOOP and dual-unit SBO which can be transferred from dual- unit LOOP. Moreover, CCF basic events for 5 diesel generators were modelled. In case of simultaneous SBO occurrences in both units, this study compared two different assumptions on the availability of the AAC D/G. As a result, when dual-unit LOOP initiating event was added to the existing single-unit PSA model, the total CDF increased by 1∼ 2% depending on the probability that the AAC D/G is available to a specific unit in case of simultaneous SBO in both units.

Estimation of the uncertainties considered in NPP PSA level 2

International Nuclear Information System (INIS)

Kalchev, B.; Hristova, R.

2005-01-01

The main approaches of the uncertainties analysis are presented. The sources of uncertainties which should be considered in PSA level 2 for WWER reactor such as: uncertainties propagated from level 1 PSA; uncertainties in input parameters; uncertainties related to the modelling of physical phenomena during the accident progression and uncertainties related to the estimation of source terms are defined. The methods for estimation of the uncertainties are also discussed in this paper

Assessment of Atorvastatin Effectiveness on Serum PSA Level in Hypercholesterolemic Males

Directory of Open Access Journals (Sweden)

Darya Khosropanah

2011-12-01

Full Text Available The previous large retrospective studies demonstrated that treatment with Statins reduces both the incidence of prostate cancer by 50% and serum Prostate Specific Antigen (PSA level up to 40%. However the main problem in those studies was the absence of control groups of men with hypercholesterolemia without Statin treatment. We performed a small prospective controlled clinical trial to assess the influence of the treatment with Atorvastatin on serum PSA in men with hypercholesterolemia referred to our educational and treatment center from October 2007 to March 2008. In this study, among the newly diagnosed males with hypercholesterolemia (LDL > 130 mg/dl, 40 patients with LDL more than 190 mg/dl were selected as a case group and were treated with Atorvastatin (20 mg/day. Among the same population and in the same period, another 40 patients with LDL between 130 and 190 mg/dl were selected as first control group and were treated only with low fat diet. Another 40 patients with normal serum cholesterol and without any treatment were selected as second control group. The lipid profile and serum PSA level of patients of all groups were tested at the first and third months after the therapy. After completion of data, the mean serum lipids and PSA level were measured in both visits and compared with each other by paired t-test. Also the mean PSA change in two visits between three groups was compared by ANOVA and Tukey HSD test. There was not any significant difference in mean baseline PSA between hypercholesterolemic and normocholesterolemic patients (P=0.547. In case group, mean PSA and LDL was reduced by 14.1% (P=0.0001 and 30% (P=0.0001 respectively by second visit. In first control group, mean PSA was not changed significantly (P=0.337, whereas mean LDL in this group was reduced by 9.6% (P= 0.0001. Similarly in the second control group mean PSA was not changed significantly (P=0.309 by second visit. In addition, mean change of PSA in case group

Main factors determining the KNP units 5 and 6 safety level according to the PSA level 1 result

International Nuclear Information System (INIS)

Manchev, B.; Marinova, B.; Nenkova, B.

2004-01-01

The Probabilistic Safety Analysis (PSA) is a powerful tool for ascertainment of the safety level reached at nuclear power plants operation. The results of PSA determine very clearly the functions, systems, equipment or operator actions that have to be improved in order to increase the plant safety level as a whole. The present report presents the main results of the last upgraded revision of PSA level 1 of units 5 and 6 of KNPP. The objective of the report is to lay emphasis on the factors determining the result obtained, i.e. to demonstrate the scopes whose improvement leads to an increase of the safety level reached at the units power operation. In the frame of the study presented the following categories of initiating events are included: Internal initiating events; Initiating events result of internal fires; Initiating events result of seismic action; Floods. Only the reactor core is considered as a source of radioactive contamination. Only initiating events related to the reactor work on power are analyzed. Unit 5 of KNPP is accepted as a basic unit for the study. All modifications and design changes implemented up to year 2000 are taken into account. The results of PSA level 1 for units 5 and 6 of KNPP covering the risk of internal initiators are presented. The assessment of the core damage due to internal initiators is based on the analysis of 18 groups of initiating events. 932 consequences and two groups of initial events are identified, leading to core damage. As a result of the quantitative calculation, over 15000 minimal cuts for the core damage are obtained. The first 80 cuts bear over 75% of the frequency obtained, and the first 700 cuts bear over 90%. Distribution of the core damage frequency by different groups of initiators is presented in tables and diagrams. A comparison of the result obtained for the reactor core damage of KNPP units 5 and 6 with assessment obtained for similar power plants is presented. The data for different NPPs are taken

Comparative evaluation of PSA-Density, percent free PSA and total PSA

OpenAIRE

Ströbel, Greta

2010-01-01

BACKGROUND The objective of this study was to evaluate the prostate specific antigen (PSA) density (PSAD) (the quotient of PSA and prostate volume) compared with the percent free PSA (%fPSA) and total PSA (tPSA) in different total PSA (tPSA) ranges from 2 ng/mL to 20 ng/mL. Possible cut-off levels depending on the tPSA should be established. METHODS In total, 1809 men with no pretreatment of the prostate were enrolled between 1996 and 2004. Total and free PSA were measured with t...

A formal guidance for handling different uncertainty sources employed in the level 2 PSA

International Nuclear Information System (INIS)

Ahn, Kwang Il; Yang, Joon Eon; Ha, Jae Joo

2004-01-01

The methodological framework of the level 2 PSA appears to be currently standardized in a formalized fashion, but there have been different opinions on the way the sources of uncertainty are characterized and treated. This is primarily because the level 2 PSA deals with complex phenomenological processes that are deterministic in nature rather than random processes, and there are no probabilistic models characterizing them clearly. As a result, the probabilistic quantification of the level 2 PSA CET/APET is often subjected to two sources of uncertainty: (a) incomplete modeling of accident pathways or different predictions for the behavior of phenomenological events and (b) expert-to-expert variation in estimating the occurrence probability of phenomenological events. While a clear definition of the two sources of uncertainty involved in the level 2 PSA makes it possible to treat an uncertainty in a consistent manner, careless application of these different sources of uncertainty may produce different conclusions in the decision-making process. The primary purpose of this paper is to characterize typical sources of uncertainty that would often be addressed in the level 2 PSA and to provide a formal guidance for quantifying their impacts on the PSA level 2 risk results. An additional purpose of this paper is to give a formal approach on how to combine random uncertainties addressed in the level 1 PSA with subjectivistic uncertainties addressed in the level 2 PSA

Methodology - PSA Regulatory handbook. Comparisons to a modern PSA study

International Nuclear Information System (INIS)

Bostroem, Urban; Jung, Gunnar; Flodin, Yngve

2003-03-01

The regulatory handbook is applicable to all types of initiating events and all operating conditions. It should be noted that it does not make the traditional subdivision of PSA into internal and external events, level 1 and level 2 PSA, or power operation and shut-down. The reason for this is that this has given the regulatory handbook a more logical structure, and that this approach underlines the integrated character of PSA when it comes to creating the plan risk profile. The regulatory handbook has been structured following the requirements on a PSA for a nuclear power plant, as this is the most demanding application. However, it is applicable also to the analysis of other nuclear installations. The purpose of the comparative review presented in this report has been to, as part of a quality review establish the PSA Handbook, compare (parts of) the handbook and its criteria with a recent PSA analysis, and to identify major discrepancies. Considerable weight has also been allocated to a review of the plant model (Risk Spectrum event trees and fault trees). The results presented in the report are not based on a complete review of the PSA in question (or of the complete PSA Handbook). Following discussions between the SKI and SwedPower, and based on the experience of the SwedPower reviewers, the following issues were chosen to be the main parts of the project: 1) General comparison according to content and transparency - Levels of ambition in PSA Handbook, PSA method description and actual PSA report. 2) Detailed comparison of: Selected component failure data - Assumptions regarding room events - CCI frequencies, realism, identification, categorisation - Taking credit for non-safety classified systems - Event tree modelling - Presentation of results 3) Fault tree model, specifically - Time frame for crediting of battery capacity - Modelling of regulators - Modelling of dependencies for room events - general quality, like how the paper documentation and the logic

Clinical diagnostic value of combined determination of serum tPSA, cPSA and IGF-I levels in patients with prostatic disorders

International Nuclear Information System (INIS)

Zhang Bashan; Zhang Zigang; Lai Fudi

2008-01-01

Objective: To investigate the diagnostic value of combined determination of serum total prostatic specific antigen (tPSA), complex prostatic specific antigen (cPSA) and IGF-I levels in patients with prostatic disorders. Methods: Serum tPSA, cPSA (with CLIA) and IGF-I (with IRMA) levels were determined in 41 patients with prostatic carcinoma, 60 patients with benign prosta- tic hypertrophy (BPH) and 55 controls. Results: The serum tPSA, cPSA and IGF-I levels in patients with prostatic cancer were significantly higher than those in patients with BPH and controls (P<0.01). Taking the cut-off values of 4ng/ml, 3.6ng/ml and 150 for tPSA, cPSA and IGF-I respectively, the combined determination of these three items would yield a sensitivity of 88.6%, specificity of 84.9%, positive predicative value of 83% and negative predicative value of 90.0% for diagnosis of prostatic cancer. Conclusion: Combined determination of tPSA, cPSA and IGF-I would yield better sensitive and accurate diagnostic rate in patients with prostatic cancer, especially in those with laboratory values within the 'grey zone'. (authors)

PSA Level 2 as element of an integral safety assessment before plant commissioning

International Nuclear Information System (INIS)

Loeffler, H.; Mildenberger, O.; Sonnenkalb, M.; Steinroetter, T.

2012-01-01

In Argentina the Central Nuclear Atucha II is near to completion. This is a pressurized heavy water reactor. PSA (Probability Safety Assessment) level 1, level 2 and level 3 have to be performed in order to show compliance with the Argentinean dose limit. Such studies have been done first by the former KWU in the 1980's to get the construction license (FABIAN 1985). Nowadays the plant owner NA-SA performs PSA level 1 and provides information about the core damage states to GRS, who does the subsequent PSA level 2 part. GRS delivers source terms to the environment and the associated frequencies to the Argentinean research institute CNEA, which performs level 3 together with NA-SA. Since GRS is situated in the middle of the chain, interface definition with both ends has been a significant task of the GRS activities. Experience gained during this process will be highlighted in the presentation. The analysis of PSA level 2 proper follows a traditional approach: -) deterministic accident simulation with integral code MELCOR; -) analyses of specific issues which are not covered by MELCOR; and -) probabilistic accident progression analysis with EVNTRE event tree methodology. It appears that MELCOR and EVNTRE and PSA guidelines in general are flexible enough to analyse new or uncommon reactor designs. It also appears that the plant specific design features may require analyses beyond present code capabilities, calling for expert judgment and they can largely determine PSA results. The behaviour of iodine is not yet covered satisfactorily by state-of-the-art models in MELCOR

Development of level 2 PSA technology

International Nuclear Information System (INIS)

Kim, Dong Ha; Park, Soo Yong; Kim, See Darl; Song, Yong Mann; Ahn, Kwang Il; Park, Jae Wu; Jin, Young Ho.

1997-07-01

The objective of this project is the development of the computer code system for level 2 probabilistic safety assessment (PSA) of nuclear power plants. The scope of the project can be divided into three areas. The first area is to develop the computer code (CONPAS) which can quantify the accident progression event trees. CONPAS beta version has been developed this year and it is comprised of four modules : 1) EDITOR for generating the event tree logic diagrams and 1) COMPUTER for event tree quantification and for additional use of the calculated results. 3) TEXT EDITOR and 4) CODE PLOTTER. Comparing with the existing computer code, the present code provides a flexible code reusability and user interface, convenient edition of logic diagram, data operation, and systematic quantification of the results. The methodology development of containment structural analysis is the second area. The specific tasks included the collection and analysis of the containment failure modes for the various containment types, and the methodology establishment for the containment structure analysis. Over twenty large dry PWR containments, the database for containment failure mode and pressure has been constructed and the simplified fragility model has been proposed to calculate the containment failure probability. They will be used as an important input not only in the containment analysis but also in the source term analysis. For the last, source term analyzing methodology and its applied computer code that is named as 'KORSOR' are developed. KORSOR which used parametric model approach combined modules which consist of accident sequence input module via user's logic rule, random sample generating module, parametric database module, and source term uncertainty quantification module. The characteristics of parametric data which use din the source term analyzing model is analyzed and the constructing idea and example for the parametric database is suggested. (author). 67 refs., 66 tabs

Achievement of the level 1 PSA in support to the CEA 2400 MWth gas-cooled fast reactor

International Nuclear Information System (INIS)

Balmain, M.; Bassi, C.; Azria, P.

2012-01-01

Within Generation IV International Forum, the CEA has developed since 2006 a Level 1 PSA to support the design of the 2400 MWth GFR (Gas-cooled Fast Reactor). A first period, with insights published in 2008, consisted in a model with few initiators representative of medium and high pressure situations, those used for the deterministic design of the Decay Heat Removal (DHR) dedicated loops. In a second period, an iterative work reached the probabilistic targets used for generation III reactors, with prior use of normal loops, and increase of DHR reliability in high pressure conditions. The PSA team covered all the internal initiators, and supported the design of components with instrumentation and control and electrical supplies, and the shutdown operating modes of secondary, tertiary circuits, with possible re-alignment to dedicated DHR loops. Besides, the completed PSA integrated more realistic success criteria than the preliminary model and than the deterministic approach, thanks to CATHARE2 code. In case of loss of Forced Convection, the probability of success of the Natural Convection DHR was assessed by a reliability method for passive systems. The paper underlines the PSA methodology knowledge from the EDF expertise, the improvements co-developed with CEA, and the iteration design-PSA-design. (authors)

Prebiopsy biparametric MRI: differences of PI-RADS version 2 in patients with different PSA levels.

Science.gov (United States)

Choi, M H; Lee, Y J; Jung, S E; Rha, S E; Byun, J Y

2018-06-09

To validate the diagnostic accuracy of Prostate Imaging-Reporting and Data System (PI-RADS) version 2 in detecting clinically significant prostate cancer (csPCa, Gleason score ≥7) on prebiopsy biparametric MRI (bpMRI) in patients with different prostate-specific antigen (PSA) levels. This retrospective study included 184 patients who underwent prebiopsy bpMRI followed by transrectal ultrasonography-guided biopsy between June 2015 and February 2017. Reader 1 performed a combination of systematic and targeted biopsy with cognitive fusion after reviewing bpMRI and reader 2 reviewed the bpMRIs retrospectively. PI-RADS categories 4 and 5 were considered positive, and the results of the biopsy were considered the reference standard. Diagnostic performance of PI-RADS of bpMRI was evaluated in two PSA groups with a PSA cut-off level of 10 ng/ml and compared to PSA and the PSA density using receiver operating characteristics (ROC) curve analysis. csPCa was diagnosed in 24 of 123 patients (19.5%) and 26 of 61 patients (42.6%) in the low and high PSA groups, respectively. A PI-RADS v2 category by either readers 1 or 2 had a significantly better performance to detect csPCa than PSA in both PSA groups. In the high PSA group, only one csPCa was missed by reader 2, but none by reader 1. In the low PSA group, readers 1 and 2 were unable to detect seven and five of the 24 csPCas, respectively. Prebiopsy bpMRI has good performance for detecting csPCa in the high PSA group but may miss small-volume csPCa in the low PSA group. Copyright © 2018 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Age-Specific Cutoff Value for the Application of Percent Free Prostate-Specific Antigen (PSA) in Chinese Men with Serum PSA Levels of 4.0–10.0 ng/ml

Science.gov (United States)

Xie, Liping; He, Dalin; Zhou, Liqun; Xu, Chuanliang; Gao, Xu; Ren, Shancheng; Wang, Fubo; Ma, Lulin; Wei, Qiang; Yin, Changjun; Tian, Ye; Sun, Zhongquan; Fu, Qiang; Ding, Qiang; Zheng, Junhua; Ye, Zhangqun; Ye, Dingwei; Xu, Danfeng; Hou, Jianquan; Xu, Kexin; Yuan, Jianlin; Gao, Xin; Liu, Chunxiao; Pan, Tiejun; Sun, Yinghao

2015-01-01

Objective The influence of age on the performance of percent free prostate-specific antigen (%fPSA) in diagnosing prostate cancer (PCa) in East Asians is controversial. We tested the diagnostic performance of %fPSA in a multi-center biopsy cohort in China and identified the proper age-specific cutoff values to avoid unnecessary biopsies. Methods Consecutive patients with a prostate-specific antigen (PSA) level of 4.0–10.0 ng/ml or 10.1–20.0 ng/ml who underwent transrectal ultrasound-guided or transperineal prostate biopsy were enrolled from 22 Chinese medical centers from Jan 1, 2010 to Dec 31, 2013. The diagnostic accuracy of PSA and %fPSA was determined using the area under the receiver operating characteristic (ROC) curve (AUC). Age-specific cutoff values were calculated using ROC curve analysis. Results The median %fPSA was much lower in younger patients compared with older patients with a PSA level of 4.0–10.0 ng/ml or 10.1–20.0 ng/ml. The AUC of %fPSA was higher than PSA only in older patients. In patients aged 50 to 59 years, %fPSA failed to improve the diagnosis compared with PSA in these two PSA ranges. Age-specific cutoff values were 24%, 27% and 32% for patients aged 60–69, 70–79 and ≥80 years, respectively, to reduce unnecessary biopsies in men with PSA levels of 4.0–10.0 ng/ml to detect 90% of all PCa. Conclusions The effectiveness of %fPSA is correlated with age in the Chinese population. Age-specific cutoff values would help avoid unnecessary biopsies in the Chinese population. PMID:26091007

Clinical outcomes and nadir prostate-specific antigen (PSA) according to initial PSA levels in primary androgen deprivation therapy for metastatic prostate cancer.

Science.gov (United States)

Kitagawa, Yasuhide; Ueno, Satoru; Izumi, Kouji; Kadono, Yoshifumi; Mizokami, Atsushi; Hinotsu, Shiro; Akaza, Hideyuki; Namiki, Mikio

2016-03-01

To investigate the clinical outcomes of metastatic prostate cancer patients and the relationship between nadir prostate-specific antigen (PSA) levels and different types of primary androgen deprivation therapy (PADT). This study utilized data from the Japan Study Group of Prostate Cancer registry, which is a large, multicenter, population-based database. A total of 2982 patients treated with PADT were enrolled. Kaplan-Meier analysis was used to compare progression-free survival (PFS) and overall survival (OS) in patients treated using combined androgen blockade (CAB) and non-CAB therapies. The relationships between nadir PSA levels and PADT type according to initial serum PSA levels were also investigated. Among the 2982 enrolled patients, 2101 (70.5 %) were treated with CAB. Although CAB-treated patients had worse clinical characteristics, their probability of PFS and OS was higher compared with those treated with a non-CAB therapy. These results were due to a survival benefit with CAB in patients with an initial PSA level of 500-1000 ng/mL. Nadir PSA levels were significantly lower in CAB patients than in non-CAB patients with comparable initial serum PSA levels. A small survival benefit for CAB in metastatic prostate cancer was demonstrated in a Japanese large-scale prospective cohort study. The clinical significance of nadir PSA levels following PADT was evident, but the predictive impact of PSA nadir on OS was different between CAB and non-CAB therapy.

Vergleichende Einschätzung der diagnostischen Aussagekraft der Kenngrößen freies PSA, Alpha1-Antichymotrypsin-PSA und komplexiertes PSA in der Diagnostik des Prostatakarzinoms

OpenAIRE

Baumgart E; Deger S; Jung K; Lein M; Loening SA; Schnorr D

2001-01-01

Ziel der Studie war die vergleichende Einschätzung der diagnostischen Aussagekraft von Gesamt-PSA (tPSA), freiem PSA (fPSA), alpha1-Antichymotrypsin-PSA (ACT-PSA) und komplexiertem PSA (cPSA) sowie der entsprechenden Quotienten zur Differenzierung zwischen einem Prostatakarzinom (PCa) und einer Benignen Prostatahyperplasie (BPH). Die Bestimmung erfolgte bei insgesamt 324 Männern (PCa: n = 144; BPH: n = 89; Kontrollen: n = 91). Die tPSA- und cPSA-Konzentrationen wurden mit dem Bayer Immuno 1 S...

Impact of radiation dose on achieving nadir PSA levels after 3-dimensional conformal radiotherapy for patients with localized prostate cancer

International Nuclear Information System (INIS)

Zelefsky, Michael J.; Leibel, Steven A.; Kelson, Suzanne; Fuks, Zvi

1996-01-01

Purpose: Several reports have documented the prognostic value of a post-irradiation nadir PSA of ≤1 ng/ml in prostatic cancer patients. The purpose of this study was to determine which pre-treatment and treatment-related variables impact upon achieving such nadir levels. Materials and Methods: Between January 1987 and June 1995, 740 patients with clinically localized prostate cancer were treated with 3-dimensional conformal radiotherapy (3D-CRT). 214 (29%) patients were treated with neo-adjuvant androgen ablation prior to therapy and were excluded from this analysis. Among the 526 evaluable patients, the clinical stage were as follows: T 1 C=128 (24%); T 2 A=76 (14%); T 2 B=116 (22%); T 2 C=99 (19%) and T 3 =107 (21%). The prescription dose to the planning target volume (PTV) was 64.8-68.4 Gy in 87 patients (17%); 70.2 Gy in 191 (36%); 75.6 Gy in 209 (40%) and 81 Gy in 39 (7%). The median pre-treatment PSA value was 11.2 ng/ml (range 0.3-114). The median follow-up was 20 months (range: 6-76 months). Results: 242 patients (46%) had PSA levels which declined to ≤1.0 ng/ml. The median time to a nadir level of ≤1.0 was 15.6 months (range: 1-43 months) from completion of 3D-CRT. 154 (29%) patients continued to show declining PSA levels within the first 2 years after therapy, and 130 patients (25%) failed to nadir at PSA levels of ≤1.0 ng/ml. Among patients with nadir PSA levels ≤1, the 3 year PSA relapse-free survival was 91% compared to 29% for patients with nadir PSA levels >1 ng/ml (p<0.0001). A Cox-regression analysis demonstrated that nadir PSA ≤1 was the strongest predictor of PSA relapse-free survival (p<0.001) followed by Gleason score ≤ 6 (p<0.001) and stage< T3 (p=0.004). Among patients who received doses of ≥75.6 Gy, the likelihood of achieving PSA nadir levels ≤1.0 at 24 and 36 months was 86% and 93%, respectively, compared to 74 and 80%, respectively, among those who received lower doses (p<0.001). Doses of ≥75.6 Gy was the strongest

Main Aspects and Results of Level 2 PSA for KNPP WWER-1000/B320

International Nuclear Information System (INIS)

Mancheva, Kaliopa

2014-01-01

The PSA Level 2 for Kozloduy NPP (KNPP) is an update of an older study with wider scope of analysis. The older study represented the status of the units up to 2001. The current PSA Level 2 is based on the PSA Level 1 and represents the status of the units up to 2007 year concerning the systems and procedures included in PSA level 1 and status up to 2011 for the systems and procedures (e.g. SAMG) related to containment and severe accident aspects. The study is performed after the PSA level 1 has been finished and approved by the customer. Compare to the older analysis all modes of operation for analyzed in PSA level 1 event groups as well Spent Fuel Pool accidents are investigated. The analysis consists of both deterministic and probabilistic analysis. As part of deterministic analysis a contemporary containment strength analysis and accident progression deterministic analysis using last version of MELCOR are performed. The probabilistic analysis contains of two part: Interface PSA and CET are calculated using Riskspectrum program code. Two types of models for CET have been developed: one for conditional probabilities calculations and a set of simplified CET's for each PDS group-for integral model. The purpose of the first model is to be able to perform quick calculations and for sensitivity analyses as well. The simplified CET's are used for integral calculation of the model. Source Term analysis is mainly based on the MELCOR analyses results. All characteristics of the releases have been defined, i.e. location, mass, energy of radionuclide groups and activity of the released isotopes (most important are reported only). The main goals of the study are to analyze the status of the containment, systems designed to prevent containment failure and operator action required under the severe accident and to give quantitative assessment of the risk parameter LERF (Large Early Release Frequency). This report will present main aspects, results, finding and

Elevated Serum PSA is Associated With Human Herpesvirus 8 Infection and Increased Circulating Cytokine Levels in Men From Tobago.

Science.gov (United States)

Henning, Jill D; Karamchandani, Jaideep M; Bonachea, Luis A; Bunker, Clareann H; Patrick, Alan L; Jenkins, Frank J

2017-05-01

Serum-prostate specific antigen (PSA) levels have been used for many years as a biomarker for prostate cancer. This usage is under scrutiny due to the fact that elevated PSA levels can be caused by other conditions such as benign prostatic hyperplasia and infections of or injury to the prostate. As a result, the identification of specific pathogens capable of increasing serum levels of PSA is important. A potential candidate responsible for elevated PSA is human herpesvirus 8 (HHV-8). We have reported previously that HHV-8 is capable of infecting and establishing a latent infection in the prostate. In this current study we test the hypothesis that HHV-8 infection is associated with elevated PSA levels. Circulating cytokine levels between men with elevated PSA and controls are also compared. HHV-8 serostatus was determined among men with elevated serum PSA (≥4 ng/ml; n = 168, no prostate cancer on biopsy) and age-matched controls (PSA PSA and 85 controls). Men with an elevated serum PSA were significantly more likely to be HHV-8 seropositive (42.9%) than the age-matched cancer-free men (22.2%; OR 2.51; 95%CI 1.48-4.29, P = 00001). Comparison of circulating cytokine levels between men with elevated serum PSA and controls indicated that elevated serum PSA is associated with a pro-inflammatory response with a mixed Th1/Th2 response while HHV-8 infection was associated with significantly higher levels of IL12p70, IL-10, and IL-13 indicating a Th2 immune response. We found a significant association between HHV-8 infection and increased levels of serum PSA. In an age of patient-centered medicine, men with an elevated serum PSA should be considered for HHV-8 serology testing to determine if HHV-8 is responsible for the elevated PSA. Prostate 77: 617-624, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Association of PSA, free-PSA and testosteron levels in serum of patients with benign prostate hyperplasia (BPH) and prostate cancer

International Nuclear Information System (INIS)

Wiwin Mailana; Kristina Dwi P; Sri Insani WW; Puji Widayati

2015-01-01

Prostate cancer screening can be done by measuring the concentration levels of PSA, free-PSA and testosterone in serum that examined with radioimmunoassay (RIA). A total of 30 patients of 45-81 years old had enrolled in this study and were taken their venous blood. The aim of research is to know the relationship between PSA and testosterone free-PSA with BPH and prostate cancer. Results showed that there was no correlation between age with BPH and prostate cancer (p = 0.06), but there is a relationship between PSA with BPH and prostate cancer (p = 0.002), the relationship between free-PSA with BPH and prostate cancer (p = 0.001). No correlation was found between PSA ratio with BPH and prostate cancer as well as the absence of a relationship between testosterone with BPH and prostate cancer (p = 0.924). (author)

Application of PSA to Assess the Safety Level of Nuclear Power Plants

International Nuclear Information System (INIS)

Berg, H. P.; Goertz, R.

2000-01-01

This paper reviews the application of PSA in German nuclear power plant regulation. From a fundamental point of view, it has to be mentioned that as stipulated in the corresponding requirements, regulatory decision making in Germany is primarily based on deterministic analyses and evaluations. Therefore, PSA is not used as a stand alone but as a supplementary basis. In this context PSA has developed a valuable tool with continuously growing importance. Level 1+ PSAs are now elaborated for all German nuclear power plants in operation, most of them are already reviewed by the competent supervisory authority and its experts. Current research activities on the federal level primarily concentrate on the further development of the methodology in the areas human factor, common cause failures, accident management measures and reduction of uncertainties in methods and data. (author)

PSA, PSA derivatives, proPSA and prostate health index in the diagnosis of prostate cancer

OpenAIRE

Ayyıldız, Sema Nur; Ayyıldız, Ali

2014-01-01

Currently, prostate- specific antigen (PSA) is the most common oncological marker used for prostate cancer screening. However, high levels of PSA in benign prostatic hyperplasia and prostatitis decrease the specificity of PSA as a cancer marker. To increase the specificity of PSA, PSA derivatives and PSA kinetics have been used. However, these new techniques were not able to increase the diagnostic specificity for prostate cancer. Therefore, the search for new molecules and derivatives of PSA...

Post-reconstruction full power and shut down level 2 PSA study for Unit 1 of Bohunice V1 NPP

International Nuclear Information System (INIS)

Kovacs, Z.

2003-01-01

The level 2 PSA model of the J. Bohunice V1 NPP was developed in the RISK SPECTRUM Professional code with the following objectives: to identify the ways in which radioactive releases from the plant can occur following the core damage; to calculate the magnitudes and frequency of the release; to provide insights into the plant behaviour during a severe accident; to provide a framework for understanding containment failure modes; the impact of the phenomena that could occur during and following core damage and have the potential to challenge the integrity of the confinement; to support the severe accident management and development of SAMGs. The magnitudes of release categories are calculated using: the MAAP4/VVER for reactor operation and shutdown mode with closed reactor vessel and the MELCOR code for shutdown mode with open reactor vessel. In this paper an overview of the Level 2 PSA methodology; description of the confinement; the interface between the level 1 and 2 PSA and accident progression analyses are presented. An evaluation of the confinement failure modes and construction of the confinement event trees as well as definition of release categories, source term analysis and sensitivity analyses are also discussed. The presented results indicate that: 1)for the full power operation - there is an 25% probability that the confinement will successfully maintain its integrity and prevent an uncontrolled fission product release; the most likely mode of release from the confinement is a confinement bypass after SGTM with conditional probability of 30%; the conditional probability for the confinement isolation failure probability without spray is 5%, for early confinement failure at the vessel failure is 4%, for other categories 1% or less; 2) for the shutdown operating modes - the shutdown risk is high for the open reactor vessel and open confinement; important severe accident sequences exists for release categories: RC5.1, RC5.2 and RC6.2

Advancement of the methodology for automated integration of external hazards into level 1 PSA modeling. Technical report; Weiterentwicklung der Methodik zur automatisierten Integration uebergreifender Einwirkungen in PSA-Modelle der Stufe 1. Technischer Fachbericht

Energy Technology Data Exchange (ETDEWEB)

Berner, Nadine; Herb, Joachim

2017-03-15

In the course of the research and development project RS1539 funded by the German Federal Ministry for Economics and Energy (BMWi) the methodology for the automated integration of hazards in Level 1 PSA models has been enhanced. Thereby, the analysis tool pyRiskRobot provides the methodological framework for mapping a generic spectrum of internal and external hazards onto complex PSA plant models. The reimplementation of the software tool via the programming language python extends the applicability and facilitates the handling of pyRiskRobot in comparison to the previous Ruby-based version RiskRobot. Moreover, the development of functions to perform the topological modelling of fault trees and the probabilistic specification of modified fault tree elements have been continued. Due to the reimplementation and further developments, the tool enables to systematically generate fault trees of varying complexity, to flexibly integrate fault trees in existing PSA models and to automatically duplicate interconnected topologies. Thus, pyRiskRobot allows the efficient and traceable realization of hazard specific, usually laborious modifications of PSA models. In addition, pyRiskRobot has been extended to serve as a functional interface between the data compilations comprising the potential influences of hazards on PSA relevant components and the data base of a PSA plant model. Based on this conceptual design, additional analyses of the data can be carried out prior to the integration within the PSA model topology. The reimplemented functionalities of pyRiskRobot have been validated with respect to reference applications, such as the modelling of an internal fire scenario, against the previous version RiskRobot. The existing method collection for the automated modification of fault tree topologies has been extended based on the requirements for further applications, among others the modelling of an external flooding scenario. The deduced hazard specific modelling approaches

Development of the fire PSA methodology and the fire analysis computer code system

International Nuclear Information System (INIS)

Katsunori, Ogura; Tomomichi, Ito; Tsuyoshi, Uchida; Yusuke, Kasagawa

2009-01-01

Fire PSA methodology has been developed and was applied to NPPs in Japan for power operation and LPSD states. CDFs of preliminary fire PSA for power operation were the higher than that of internal events. Fire propagation analysis code system (CFAST/FDS Network) was being developed and verified thru OECD-PRISME Project. Extension of the scope for LPSD state is planned to figure out the risk level. In order to figure out the fire risk level precisely, the enhancement of the methodology is planned. Verification and validation of phenomenological fire propagation analysis code (CFAST/FDS Network) in the context of Fire PSA. Enhancement of the methodology such as an application of 'Electric Circuit Analysis' in NUREG/CR-6850 and related tests in order to quantify the hot-short effect precisely. Development of seismic-induced fire PSA method being integration of existing seismic PSA and fire PSA methods is ongoing. Fire PSA will be applied to review the validity of fire prevention and mitigation measures

Establishment of Infrastructure for Domestic-Specific Level 3 PSA based on MACCS2

Energy Technology Data Exchange (ETDEWEB)

Jang, Seung-Cheol; Han, Seok-Jung; Choi, Sun-Yeong; Lee, Seung-Jun [KAERI, Daejeon (Korea, Republic of); Kim, Wan-Seob [Korea Reliability Technology and System, Daejeon (Korea, Republic of)

2015-05-15

Research activities related to the Level 3 PSA have naturally disappeared since the use of risk surrogates. Recently, Level 3 PSA was only performed to the extent of the purpose of operating license for the plant under construction. Since the Fukushima accident, concern about a comprehensive site-specific Level 3 PSA has been raised for some compelling reasons, especially the evaluation of the domestic multi-unit site risk effect including other site radiological sources (e.g., spent fuel pool, multi-units). Unfortunately, there are no domestic-specific consequence analysis code and input database required to perform a site-specific Level 3 PSA. The paper focuses on the development of the input data management system for domestic-specific Level 3 PSA based MACCS2 (MELCOR Accident Consequence Code System). The authors call it KOSCA-MACCS2 (Korea Off-Site Consequence Analysis based in MACCS2). It serves as an integrated platform for a domestic-specific Level 3 PSA. Also, it provides the pre-processing modules to automatically generate MACCS2 input from diverse types of the domestic-specific data including numerical map data, e.g., meteorological data, numerical population map, digital land use map, economic statistics and so on. Note that some functions should be still developed and added on it, e.g., post-processing module to convert MACCS2 outputs to graphic report forms, and so on. Henceforth, it is necessary to develop a Korean-specific Level 3 PSA code as a substitution for the foreign software, MACCS2.

Best-practices guidelines for L2PSA development and applications. Volume 1 - General

International Nuclear Information System (INIS)

Raimond, E.; Pichereau, F.; Durin, T.; Rahni, N.; Loeffler, H.; Roesch, O.; Lajtha, G.; Santamaria, C.S.; Dienstbier, J.; Rydl, A.; Holmberg, J.E.; Lindholm, I.; Maennistoe, I.; Pauli, E.M.; Dirksen, G.; Grindon, L.; Peers, K.; Bassi, C.; Hulqvist, G.; Parozzi, F.; Polidoro, F.; Cazzoli, E.; Vitazkova, J.; Burgazzi, L.; Brinkman, H.; Seidel, A.; Schubert, B.; Wohlstein, R.; Guentay, S.; Oury, L.; Ngatchou, C.; Siltanen, S.; Niemela, I.; Routamo, T.; Vincon, L.; Helstroem, P.

2010-01-01

The objective of this coordinated action was to develop best practice guidelines for the performance and application of Level 2 PSA with a view to achieve harmonisation at EU level and to allow a meaningful and practical uncertainty evaluation in a Level 2 PSA. Specific relationships with communities in charge of nuclear reactor safety (utilities, safety authorities, vendors, and research or services companies) have been established in order to define the current needs in terms of guidelines for Level 2 PSA development and application. An international workshop was organised in Hamburg, with the support of VATTENFALL, in November 2008. The Level 2 PSA experts from ASAMPSA2 project partners have proposed some guidelines for the development and application of L2PSA based on their experience, open literature, and on information available from international cooperation (EC Severe Accident network of Excellence - SARNET, IAEA standards, OECD-NEA publications and workshop). There are a large number of technical issues addressed in the guideline which are not all covered with the same level of detail in the first version of the guideline. This version was submitted for external review in November 2010 by severe accident and PSA experts (especially from SARNET and OECD-NEA members). The feedback of the external review will be dis cussed during an international open works hop planned for March 2011 and all outcomes will be taken into consideration in the final version of this guideline (June 2011). The guideline includes 3 volumes: - Volume 1 - General considerations on L2PSA. - Volume 2 - Technical recommendations for Gen II and III reactors. - Volume 3 - Specific considerations for future reactors (Gen IV). The recommendations formulated in the guideline should not be considered as 'mandatory' but should help Level 2 PSA developers to achieve high quality studies with limited time and resources. It may also help Level 2 PSA reviewers by positioning one specific study in

68Ga-PSMA PET/CT for the detection of bone metastasis in recurrent prostate cancer and a PSA level <2 ng/ml

DEFF Research Database (Denmark)

Petersen, Lars J; Nielsen, Julie B; Dettmann, Katja

2017-01-01

/computed tomography ((68)Ga-PSMA PET/CT) is a novel and promising method for imaging in prostate cancer. The present study reports two cases of patients with prostate cancer with biochemical recurrence, with evidence of bone metastases on (68)Ga-PSMA PET/CT images and low prostate specific antigen PSA levels (.../ml) and PSA doubling time >6 months. The bone metastases were verified by supplementary imaging with (18)F-sodium fluoride PET/CT and magnetic resonance imaging as well as biochemical responses to androgen deprivation therapy. Therefore, (68)Ga-PSMA PET/CT is promising for the restaging of patients...... with prostate cancer with biochemical recurrence, including patients with low PSA levels and low PSA kinetics....

Evaluation of total PSA assay on vitros ECi and correlation with Kryptor-PSA assay.

Science.gov (United States)

Cassinat, B; Wacquet, M; Toubert, M E; Rain, J D; Schlageter, M H

2001-01-01

An increasing number of multiparametric immuno-analysers for PSA assays are available. As different immuno-assays may vary in their analytical quality and their accuracy for the follow-up of patients, expertise is necessary for each new assay. The PSA assay on the Vitros-ECi analyser has been evaluated and compared with the PSA assay from the Kryptor analyser. Variation coefficients were 0.91 to 1.98% for within-run assays, and 4.2% to 5.4% for interassay (PSA levels = 0.8 microgram/L to 33.6 micrograms/L). Dilution tests showed 93 to 136% recovery until 70 micrograms/L PSA. Functional sensitivity was estimated at 0.03 microgram/L. Equimolarity of the test was confirmed. Correlation of PSA levels measured with Vitros-ECi and Kryptor analysers displayed a correlation coefficient r2 of 0.9716. The half-lives and doubling times of PSA were similar using both methods. Vitros-ECi PSA assay meets the major criteria for the management of prostate cancer patients.

Diagnostic value of combined tet of cPSA, IGF-1 and TGFα for prostate cancer

International Nuclear Information System (INIS)

Dai Feng; Yang Qingling

2006-01-01

To assess the clinical value of serum complexed prostate specific antigen (cPSA), insulinlike growth factor(IGF-1),transforming growth factor a (TGFα) in the diagnosis of pros- tate cancer (PCα), serum samples were obtained from 46 men with PCa, 64 men with untreated benign prostatic hyperplasia(BPH) and 73 men of a healthy control group. The levels of cPSA, IGF-1 and TGFα were determined by autoimmunochemistry luminescence method, IRMA and RIA method. Postoperative observation was conducted for the change of cPSA, IGF-1 and TGFa in the serum from men with PCa obtained in one month, three months and six months after the operations. Results showed that the levels of cPSA, IGF-1 and TGFα in PCa serum were significantly higher than the BPH group and control group(P 0.05). The combined test of cPSA, IGF-1 and TGFα is meaningful for the prevision, diagnosis and therapy of PCa. (authors)

Treatment strategy for metastatic prostate cancer with extremely high PSA level: reconsidering the value of vintage therapy.

Science.gov (United States)

Yamada, Yasutaka; Sakamoto, Shinichi; Amiya, Yoshiyasu; Sasaki, Makoto; Shima, Takayuki; Komiya, Akira; Suzuki, Noriyuki; Akakura, Koichiro; Ichikawa, Tomohiko; Nakatsu, Hiroomi

2018-05-04

The prognostic significance of initial prostate-specific antigen (PSA) level for metastatic prostate cancer remains uncertain. We investigated the differences in prognosis and response to hormonal therapies of metastatic prostate cancer patients according to initial PSA levels. We analyzed 184 patients diagnosed with metastatic prostate cancer and divided them into three PSA level groups as follows: low (PSA progression-free survival (PFS) for first-line ADT and overall survival (OS) within each of the three groups. Furthermore, we analyzed response to antiandrogen withdrawal (AW) and alternative antiandrogen (AA) therapies after development of castration-resistant prostate cancer (CRPC). No significant differences in OS were observed among the three groups (P = 0.654). Patients with high PSA levels had significantly short PFS for first-line ADT (P = 0.037). Conversely, patients in the high PSA level group had significantly longer PFS when treated with AW than those in the low PSA level group (P = 0.047). Furthermore, patients with high PSA levels had significantly longer PFS when provided with AA therapy (P = 0.049). PSA responders to AW and AA therapies had significantly longer survival after CRPC development than nonresponders (P = 0.011 and P PSA level predicted favorable response to vintage sequential ADT and AW. The current data suggest a novel aspect of extremely high PSA value as a favorable prognostic marker after development of CRPC.

Improving PSA quality of KSNP PSA model

International Nuclear Information System (INIS)

Yang, Joon Eon; Ha, Jae Joo

2004-01-01

In the RIR (Risk-informed Regulation), PSA (Probabilistic Safety Assessment) plays a major role because it provides overall risk insights for the regulatory body and utility. Therefore, the scope, the level of details and the technical adequacy of PSA, i.e. the quality of PSA is to be ensured for the successful RIR. To improve the quality of Korean PSA, we evaluate the quality of the KSNP (Korean Standard Nuclear Power Plant) internal full-power PSA model based on the 'ASME PRA Standard' and the 'NEI PRA Peer Review Process Guidance.' As a working group, PSA experts of the regulatory body and industry also participated in the evaluation process. It is finally judged that the overall quality of the KSNP PSA is between the ASME Standard Capability Category I and II. We also derive some items to be improved for upgrading the quality of the PSA up to the ASME Standard Capability Category II. In this paper, we show the result of quality evaluation, and the activities to improve the quality of the KSNP PSA model

Cutset Quantification Error Evaluation for Shin-Kori 1 and 2 PSA model

International Nuclear Information System (INIS)

Choi, Jong Soo

2009-01-01

Probabilistic safety assessments (PSA) for nuclear power plants (NPPs) are based on the minimal cut set (MCS) quantification method. In PSAs, the risk and importance measures are computed from a cutset equation mainly by using approximations. The conservatism of the approximations is also a source of quantification uncertainty. In this paper, exact MCS quantification methods which are based on the 'sum of disjoint products (SDP)' logic and Inclusion-exclusion formula are applied and the conservatism of the MCS quantification results in Shin-Kori 1 and 2 PSA is evaluated

Severe Accident Research Network (SARNET). Level 2 PSA work package: comparison of partners methods for uncertainties assessment

International Nuclear Information System (INIS)

Chaumont, B.; Haesendonck, M.; Vidal, S.; Eyink, J.; Loeffler, H.; Radu, G.; Kopustinskas, V.; Ming, A.; Guntay, S.; Gustavsson, V.; Ivanov, I.; Dienstbier, J.; Bareith, A.; Hollo, E.; Lajtha, G.

2007-01-01

The PSA2 work package (PSA2 WP) is a part of the Joined Programme Activity of the European Severe Accident Network (SARNET) related to level 2 PSA methodologies. The general objectives of this work package is to provide a comparison of the different methodologies used or under development for level 2 PSA application by the partners involved in the work package and to promote their harmonization. The PSA2 WP is organized into three main topics: methodologies in general, methodologies for uncertainties assessment, and dynamic reliability methods. The different tasks initially defined for these three topics are shortly described and the partners involved identified. Attention is then paid on the methodologies used so far by the different partners to assess the uncertainties in their level 2 PSA. A review of partners approaches to assess - as far as possible - the different sources of possible uncertainties is done for the different following topics: - uncertainties propagated from the level 1 PSA, - uncertainties (in sense of approximation) due to the binning of the level 1 sequences in Plant Damage, - uncertainties related to the structure of the Accident Progression Event Tree, - uncertainties related to the probabilities of stochastic events (system failure or recovery, human actions, some physical phenomena such as ignition of hydrogen combustion or triggering of steam explosion), - uncertainties elated to the modelling of the different physical phenomena, - uncertainties related to the cut-off frequency used in the probabilistic quantification of the Accident Progression Event Tree; - uncertainties related to the binning of level 2 sequences in Release Categories (variables not considered, values of eventual continuous variables). First conclusions of the comparison are given in terms of improvement needs and then of perspectives of the work for the following period of work. (authors)

The Effect of Increasing Doses of Saw Palmetto Fruit Extract on Serum PSA Levels: Analysis of the CAMUS Randomized Trial

Science.gov (United States)

Andriole, Gerald L.; McCullum-Hill, Christie; Sandhu, Gurdarshan S.; Crawford, E. David; Barry, Michael J.; Cantor, Alan

2014-01-01

Purpose Saw palmetto extracts are used for treating lower urinary tract symptoms in men despite level I evidence concluding that saw palmetto was ineffective in reducing lower urinary symptoms. We sought to determine whether higher doses of saw palmetto as studied in CAMUS affect serum PSA levels. Materials and Methods The CAMUS trial was a randomized, placebo-controlled double blind multi-centered North American trial conducted between June 5, 2008 and October 10, 2012 in which 369 men >45 years of age with AUA symptom score ≥ 8 and ≤ 24 were randomly assigned to placebo or dose escalation saw palmetto, which consisted of 320mg for first 24 weeks to 640mg for next 24 weeks to 960mg for last 24 weeks of this 72 week trial. Serum PSA levels (Beckman-Coulter) were obtained at baseline and at weeks 24, 48 and 72 and were compared between treatment groups using the pooled t and Fisher's exact tests. Results Serum PSA levels were similar at baseline for the placebo (1.93 ± 1.59 ng/ml) and saw palmetto groups (2.20 ± 1.95, p = 0.16). Changes in PSA levels over the course of the study were similar: placebo group mean change 0.16 ± 1.08 ng/ml and saw palmetto group mean change 0.23 ± 0.83 ng/ml (p value 0.50). Additionally, no differential effect on serum PSA levels was observed between treatment arms when groups were stratified by baseline PSA values. Conclusions Saw palmetto extract does not affect serum PSA levels more than placebo even at relatively high doses. PMID:23253958

Influence of PSA, PSA velocity and PSA doubling time on contrast-enhanced 18F-choline PET/CT detection rate in patients with rising PSA after radical prostatectomy

International Nuclear Information System (INIS)

Schillaci, Orazio; Calabria, Ferdinando; Tavolozza, Mario; Caracciolo, Cristiana Ragano; Orlacchio, Antonio; Danieli, Roberta; Simonetti, Giovanni; Agro, Enrico Finazzi; Miano, Roberto

2012-01-01

To evaluate the accuracy of contrast-enhanced 18 F-choline PET/CT in restaging patients with prostate cancer after radical prostatectomy in relation to PSA, PSA velocity (PSAve) and PSA doubling time (PSAdt). PET/CT was performed in 49 patients (age range 58-87 years) with rising PSA (mean 4.13 ng/ml) who were divided in four groups according to PSA level: ≤1 ng/ml, 1 to ≤2 ng/ml, 2 to ≤4 ng/ml, and >4 ng/ml. PSAve and PSAdt were measured. PET and CT scans were interpreted separately and then together. PET/CT diagnosed relapse in 33 of the 49 patients (67%). The detection rates were 20%, 55%, 80% and 87% in the PSA groups ≤1, 1 to ≤2, 2 to ≤4 and >4 ng/ml, respectively. PET/CT was positive in 7 of 18 patients (38.9%) with a PSA ≤2 ng/ml, and in 26 of 31 (83.9%) with a PSA >2 ng/ml. PET/CT was positive in 7 of 25 patients (84%) with PSAdt ≤6 months, and in 12 of 24 patients (50%) with PSAdt >6 months, and was positive in 26 of 30 patients (86%) with a PSAve >2 ng/ml per year, and in 7 of 19 patients (36.8%) with PSAve ≤2 ng/ml per year. PET alone was positive in 31 of 49 patients (63.3%), and of these 31 patients, CT was negative in 14 but diagnosed bone lesions in 2 patients in whom PET alone was negative. CT with the administration of intravenous contrast medium did not provide any further information. Detection rate of 18 F-choline imaging is closely related to PSA and PSA kinetics. In particular, 18 F-choline PET/CT is recommended in patients with PSA >2 ng/ml, PSAdt ≤6 months and PSAve >2 ng/ml per year. CT is useful for detecting bone metastases that are not 18 F-choline-avid. The use of intravenous contrast agent seems unnecessary. (orig.)

Analysis of convergence of uncertainty and important factors affecting uncertainty in level 1 PSA for pressurized water reactors

International Nuclear Information System (INIS)

Shimada, Yoshio

2002-01-01

We analyzed how the convergence of mean core damage frequency (CDF) depends on the number of minimal cut sets, the sampling method and the random seed, using level 1 PSA models for Surry 1 and a Japanese 4 loop PWR plant. As a result, the followings were clarified: the good convergence efficiency of the latin hypercube sampling (LHS), the relationship between number of minimal cut sets and mean CDF, as well as the standard deviation and the easy method of judgment for mean CDF convergence. In addition, it was seen that the relationship between the number of probability variables (i.e. the number of basic events) and the number of samplings needed to converge for mean CDF. Analysis of important factors affecting uncertainty was also performed. As a result, it was found that the initiating events (especially loss of coolant accidents) were the dominant important factors. Finally, comparisons were made for the 95% confidence interval of the calculated results from the operating experience of the worldwide nuclear power plants with (1) the mean core damage frequency by PSA for 108 US plants and 51 Japanese plants and (2) the 95% confidence interval of the US and the Japanese Plant PSA model used in this research. As a result, it was clarified that the mean core damage frequency of almost all US pressurized and boiling light water reactors in the US was in the 90% confidence interval calculated from the operating experience of the nuclear power plants (PWRs and BWRs) in the world, but that of those reactors in Japan was smaller then that level. (author)

Analysis of convergence of uncertainty and important factors affecting uncertainty in level 1 PSA for pressurized water reactors

Energy Technology Data Exchange (ETDEWEB)

Shimada, Yoshio [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan)

2002-09-01

We analyzed how the convergence of mean core damage frequency (CDF) depends on the number of minimal cut sets, the sampling method and the random seed, using level 1 PSA models for Surry 1 and a Japanese 4 loop PWR plant. As a result, the followings were clarified: the good convergence efficiency of the latin hypercube sampling (LHS), the relationship between number of minimal cut sets and mean CDF, as well as the standard deviation and the easy method of judgment for mean CDF convergence. In addition, it was seen that the relationship between the number of probability variables (i.e. the number of basic events) and the number of samplings needed to converge for mean CDF. Analysis of important factors affecting uncertainty was also performed. As a result, it was found that the initiating events (especially loss of coolant accidents) were the dominant important factors. Finally, comparisons were made for the 95% confidence interval of the calculated results from the operating experience of the worldwide nuclear power plants with (1) the mean core damage frequency by PSA for 108 US plants and 51 Japanese plants and (2) the 95% confidence interval of the US and the Japanese Plant PSA model used in this research. As a result, it was clarified that the mean core damage frequency of almost all US pressurized and boiling light water reactors in the US was in the 90% confidence interval calculated from the operating experience of the nuclear power plants (PWRs and BWRs) in the world, but that of those reactors in Japan was smaller then that level. (author)

Evaluation of prostate cancer prevalence in Iranian male population with increased PSA level, a one center experience

International Nuclear Information System (INIS)

Moslemi, Mohammad Kazem; Lotfi, Fariborz; Tahvildar, Seyed Ali

2011-01-01

This study was conducted to evaluate the incidence of prostate cancer (PCa) in Iranian male patients with increased prostate-specific antigen (PSA), and normal or abnormal digital rectal examination (DRE) that underwent prostate biopsy. From March 2006 to April 2009, a total of 346 consecutive males suspected of having PCa due to increased PSA levels underwent transrectal ultrasonography (TRUS)-guided sextant biopsy of the prostate. The total PSA (tPSA), demographic data, incidence of PCa, benign prostate hyperplasia (BPH), and prostatitis were assessed. The patients were divided into two groups according to their PSA values (group A serum tPSA level, 4–10 ng/mL; group B serum tPSA level, 10.1–20.0 ng/mL). Of the 346 biopsied cases, 193 cases (56%) had PCa, 80 cases (23%) had BPH, and 73 cases (21%) had prostatitis. The mean PSA and the age of the carcinoma group were significantly higher than those of the benign group (P < 0.01). The biopsy results were grouped as PCa, BPH, and prostatitis. Incidence of PCa for group A and group B cases were 115 cases (51%), and 78 cases (65%), respectively. In the case of PCa, BPH, and prostatitis, the mean PSAs were 10.02 ng/mL, 8.76 ng/mL, and 8.41 ng/mL, respectively (P < 0.40). TRUS-guided prostate biopsy and interpretation by a skilled team is highly recommended for early detection of PCa or its ruling-out. It seems that a PSA cutoff value of 4 ng/mL may be applied to the Iranian population. Although the chance of PCa is high in the PSA levels of 4–10 ng/mL, the combination of some data, like age and prostate volume, can decrease the rate of unnecessary prostate biopsies. We recommend prostate biopsy when PSA and/or DRE is elevated in symptomatic patients with obstructive and/or irritative lower urinary tract symptoms (LUTS) such as dysuria, frequency, or nocturia. Due to the very high incidence of PCa in the patients with PSA greater than 10 ng/mL, TRUS-guided biopsy is indicated, whatever the findings on DRE and

MODIFICATION OF THE SPAR-H METHOD TO SUPPORT HRA FOR LEVEL 2 PSA

Energy Technology Data Exchange (ETDEWEB)

St. Germain, S.; Boring, R.; Banaseanu, G.; Akl, Y.; Xu, M.

2016-10-01

Currently, available Human Reliability Analysis (HRA) methods were generally developed to support Level 1 Probabilistic Safety Analysis (PSA) models. There has been an increased emphasis placed on Level 2 PSA in recent years; however, the currently used HRA methods are not ideal for this application, including the SPAR-H method. Challenges that will likely be present during a severe accident such as degraded or hazardous operating conditions, shift in control from the main control room to the technical support center, unavailability of instrumentation, and others are not routinely considered for Level 1 HRA analysis. These factors combine to create a much more uncertain condition to be accounted for in the HRA analysis. While the SPAR-H shaping factors were established to support Level 1 HRA, previous studies have shown it may be used for Level 2 HRA analysis as well. The Canadian Nuclear Safety Commission (CNSC) and Idaho National Laboratory (INL) in a joint project are investigating modifications to the SPAR-H method to create more consistency in applying the performance shaping factors used in the method for Level 2 analysis.

Stage T1-2 prostate cancer with pretreatment PSA 10 ng/ml or less: radiotherapy or surgery?

International Nuclear Information System (INIS)

Keyser, Douglas; Kupelian, Patrick; Zippe, Craig; Klein, Eric

1996-01-01

Purpose: Presently, patients with pretreatment PSA levels ≤10 ng/ml constitute the majority of cases presenting for definitive treatment. Our aim was to determine whether the type of treatment (radiotherapy versus surgery) affected biochemical failure rates in this group of patients. This study is based on 389 patients treated at a single institution. Material and Methods: The charts of all patients treated with either radiotherapy or prostatectomy alone between 1987 and 1993 were reviewed (n=811). Patients with clinical stage T1 or T2 disease, and a pretreatment PSA level (iPSA) of 10.0 or less were analyzed (n=389). Two hundred forty nine (64%) received radical prostatectomy and 140 (36%) received radiotherapy (median dose 66.6 Gy). Pretreatment patient characteristics including clinical stage, biopsy Gleason score (GS) and iPSA level were not significantly different between the radiation and surgery groups (Table 1). The patients treated with radiation were significantly older (median age 70 years vs. 64 years, p<0.05). A total of 37% of the prostatectomy patients had a positive margin. The median follow-up time was 33 months; 1458 follow-up PSA levels were available for analysis. Biochemical failure was defined as a rise in PSA level of 1.0 ng/ml above the nadir PSA level in radiotherapy cases, or any value above 0.2 ng/ml in the prostatectomy cases. Results: The overall 5 year actuarial biochemical relapse free survival (bRFS) rate was 70%. The 5-year bRFS rates for prostatectomy and radiotherapy were identical (70%) (Fig.1). The significant factors affecting bRFS rates were iPSA level (≤4 vs. 4-10 ng/ml) and Gleason score (≤6 vs. ≥7) (Table 2). The 5-year bRFS rates of patients with iPSA ≤4 vs. iPSA 4-10 ng/ml were 92% vs. 61% respectively, p<0.01. The 5-year clinical relapse free survival was 93%. All clinical failures were preceded by biochemical failure. Patients with positive surgical margins did significantly worse than those with negative

Influence of PSA, PSA velocity and PSA doubling time on contrast-enhanced {sup 18}F-choline PET/CT detection rate in patients with rising PSA after radical prostatectomy

Energy Technology Data Exchange (ETDEWEB)

Schillaci, Orazio [University ' ' Tor Vergata' ' , Department of Biopathology and Diagnostic Imaging, Interventional, Rome (Italy); IRCCS Neuromed, Department of Nuclear Medicine and Molecular Imaging, Pozzilli (Italy); Calabria, Ferdinando [IRCCS Neuromed, Department of Nuclear Medicine and Molecular Imaging, Pozzilli (Italy); Tavolozza, Mario; Caracciolo, Cristiana Ragano; Orlacchio, Antonio; Danieli, Roberta; Simonetti, Giovanni [University ' ' Tor Vergata' ' , Department of Biopathology and Diagnostic Imaging, Interventional, Rome (Italy); Agro, Enrico Finazzi; Miano, Roberto [University Hospital ' ' Tor Vergata' ' , Department of Urology, Rome (Italy)

2012-04-15

To evaluate the accuracy of contrast-enhanced {sup 18}F-choline PET/CT in restaging patients with prostate cancer after radical prostatectomy in relation to PSA, PSA velocity (PSAve) and PSA doubling time (PSAdt). PET/CT was performed in 49 patients (age range 58-87 years) with rising PSA (mean 4.13 ng/ml) who were divided in four groups according to PSA level: {<=}1 ng/ml, 1 to {<=}2 ng/ml, 2 to {<=}4 ng/ml, and >4 ng/ml. PSAve and PSAdt were measured. PET and CT scans were interpreted separately and then together. PET/CT diagnosed relapse in 33 of the 49 patients (67%). The detection rates were 20%, 55%, 80% and 87% in the PSA groups {<=}1, 1 to {<=}2, 2 to {<=}4 and >4 ng/ml, respectively. PET/CT was positive in 7 of 18 patients (38.9%) with a PSA {<=}2 ng/ml, and in 26 of 31 (83.9%) with a PSA >2 ng/ml. PET/CT was positive in 7 of 25 patients (84%) with PSAdt {<=}6 months, and in 12 of 24 patients (50%) with PSAdt >6 months, and was positive in 26 of 30 patients (86%) with a PSAve >2 ng/ml per year, and in 7 of 19 patients (36.8%) with PSAve {<=}2 ng/ml per year. PET alone was positive in 31 of 49 patients (63.3%), and of these 31 patients, CT was negative in 14 but diagnosed bone lesions in 2 patients in whom PET alone was negative. CT with the administration of intravenous contrast medium did not provide any further information. Detection rate of {sup 18}F-choline imaging is closely related to PSA and PSA kinetics. In particular, {sup 18}F-choline PET/CT is recommended in patients with PSA >2 ng/ml, PSAdt {<=}6 months and PSAve >2 ng/ml per year. CT is useful for detecting bone metastases that are not {sup 18}F-choline-avid. The use of intravenous contrast agent seems unnecessary. (orig.)

PSA kinetics after prostate brachytherapy: PSA bounce phenomenon and its implications for PSA doubling time

International Nuclear Information System (INIS)

Ciezki, Jay P.; Reddy, Chandana A.; Garcia, Jorge; Angermeier, Kenneth; Ulchaker, James; Mahadevan, Arul; Chehade, Nabil; Altman, Andrew; Klein, Eric A.

2006-01-01

using the bF3 definition and 8.8 months using the bFn+2 definition. However, a significant difference was found in the time to the first rise in PSA after PI for patients with a PSA bounce vs. patients with bF. The median time to the first rise in PSA after nadir for those with a PSA bounce was 15.1 months vs. 30.0 months using the bF3 definition (p = 0.001) and 22.3 months using the bFn+2 definition (p = 0.013). Conclusion: Patients experiencing a PSA bounce are more likely to be younger and will have a better bRFS. The PSADT cannot differentiate a PSA bounce from bF. The time to the initial PSA rise after nadir is an excellent discriminator of bF from PSA bounce. The time of the PSA rise after nadir occurs far sooner for a PSA bounce than for bF. This factor should be considered when assessing a patient with a rising PSA level after PI before a patient is administered salvage therapy

Failure to Achieve a PSA Level ≤1 ng/mL After Neoadjuvant LHRHA Therapy Predicts for Lower Biochemical Control Rate and Overall Survival in Localized Prostate Cancer Treated With Radiotherapy

International Nuclear Information System (INIS)

Mitchell, Darren M.; McAleese, Jonathan; Park, Richard M.; Stewart, David P.; Stranex, Stephen; Eakin, Ruth L.; Houston, Russell F.; O'Sullivan, Joe M.

2007-01-01

Purpose: To investigate whether failure to suppress the prostate-specific antigen (PSA) level to ≤1 ng/mL after ≥2 months of neoadjuvant luteinizing hormone-releasing hormone agonist therapy in patients scheduled to undergo external beam radiotherapy for localized prostate carcinoma is associated with reduced biochemical failure-free survival. Methods and Materials: A retrospective case note review of consecutive patients with intermediate- or high-risk localized prostate cancer treated between January 2001 and December 2002 with neoadjuvant hormonal deprivation therapy, followed by concurrent hormonal therapy and radiotherapy was performed. Patient data were divided for analysis according to whether the PSA level in Week 1 of radiotherapy was ≤1.0 ng/mL. Biochemical failure was determined using the American Society for Therapeutic Radiology and Oncology (Phoenix) definition. Results: A total of 119 patients were identified. The PSA level after neoadjuvant hormonal deprivation therapy was ≤1 ng/mL in 67 patients and >1 ng/mL in 52. At a median follow-up of 49 months, the 4-year actuarial biochemical failure-free survival rate was 84% vs. 60% (p = 0.0016) in favor of the patients with a PSA level after neoadjuvant hormonal deprivation therapy of ≤1 ng/mL. The overall survival rate was 94% vs. 77.5% (p = 0.0045), and the disease-specific survival rate at 4 years was 98.5% vs. 82.5%. Conclusions: The results of our study have shown that patients with a PSA level >1 ng/mL at the beginning of external beam radiotherapy after ≥2 months of neoadjuvant luteinizing hormone-releasing hormone agonist therapy have a significantly greater rate of biochemical failure and lower survival rate compared with those with a PSA level of ≤1 ng/mL. Patients without adequate PSA suppression should be considered a higher risk group and considered for dose escalation or the use of novel treatments

Applicability of living PSA in NPP modernization

International Nuclear Information System (INIS)

Himanen, R.

1999-01-01

Recently the utility Teollisuuden Voima Oy (TVO) has modernized the Olkiluoto 1 and 2 nuclear units and increased the net electric power by 18 per cent. Level 2 PSA was performed during the modernization project and the living level 1 PSA was used to support the design of the plant modifications. The plant specific living PSA model was a powerful tool when evaluating modernization alternatives. Successive support of safety management with the PSA model requires, that both the utility and the Regulatory Body understand capability and limitations of the model in details. TVO has prepared an internal procedure that presents in detail the practices and responsibilities concerning living PSA. The procedure is based on general guidelines and requirements on probabilistic safety analysis of nuclear power plants in Finland, released by the Regulatory Body. Living PSA requires that also the procedure for the use of living PSA is living. The recently published USNRC Regulatory Guides on PSA will be taken into account in the next version of the TVO PSA procedure. The PSA Peer Review Certification Process is one way to evaluate the quality of PSA in general, but also to detect the weaknesses of the PSA. However, the Certification Process cover only limited scope of PSA omitting e.g. all other external events except internal floods. This paper gives an overview on the scope of living PSA for Olkiluoto 1 and 2, and presents some examples on the real use of PSA concerning the modernization of the plant. Definition of quantitative dependability requirements for renovated systems is possible, but on the other hand, proving of these targets is in some cases extremely difficult, because of lacking dependability data. The problems are mainly concerned in systems with of programmable logic control. (au)

The development of a relationship framework between LERF and Level-3 PSA

International Nuclear Information System (INIS)

Jae, Moo Sung; Jin, Young Ho; Kang, Kyung Min; Lee, Chang Ju

2009-01-01

The concept of LERF(Large Early Release Frequency) has been considered as a suitable metrics for making risk-informed regulatory decisions. However, the definition of 'large early release' and the associated time needs to be evaluated from the regulatory perspective and the potential implication of severe accidents. The definition of what constitutes a large early release differs a lot, and there are many parameters involved in the definition, the most important ones being the time, the amount, and the composition of the release. The underlying reason for the complexity of the release definition largely depends on the fact that the release assessment constitutes the link between the level-2 PSA results and the health effects from the release. Basically, such consequence issues are addressed in level-3 PSA, and can only be fully covered in level-3 analysis. In order to judge the acceptability of consequence results, various criteria relating between LERF and results from level 3 PSA need to be defined

Repeat prostate-specific antigen (PSA) test before prostate biopsy: a 20% decrease in PSA values is associated with a reduced risk of cancer and particularly of high-grade cancer.

Science.gov (United States)

De Nunzio, Cosimo; Lombardo, Riccardo; Nacchia, Antonio; Tema, Giorgia; Tubaro, Andrea

2018-07-01

To analyse the impact of repeating a prostate-specific antigen (PSA) level assessment on prostate biopsy decision in a cohort of men undergoing prostate biopsy. From 2015 onwards, we consecutively enrolled, at a single institution in Italy, men undergoing 12-core transrectal ultrasonography-guided prostate needle biopsy. Indication for prostate biopsy was a PSA level of ≥4 ng/mL. Demographic, clinical, and histopathological data were collected. The PSA level was tested at enrolment (PSA 1 ) and 4 weeks later on the day before biopsy (PSA 2 ). Variations in PSA level were defined as: stable PSA 2 within a 10% variation, stable PSA 2 within a 20% variation, PSA 2 decreased by ≥10%, PSA 2 decreased by ≥20%, PSA 2 increased by ≥10%, PSA 2 increased by ≥20%, and PSA 2 PSA within 20% variation had a higher risk of prostate cancer (odds ratio [OR] 1.80, P PSA2 decreased by ≥20% had a lower risk of prostate cancer (OR 0.37, P PSA2 increased by ≥10% had an increased risk of high-grade prostate cancer (OR 1.93, P PSA returned to normal values (PSA levels significantly reduced the risk of high-grade prostate cancer. Further multicentre studies should validate our present results. © 2018 The Authors BJU International © 2018 BJU International Published by John Wiley & Sons Ltd.

The correlation of PSA nadir and biochemical freedom from cancer after external beam treatment: effects of stage, grade and pretreatment PSA groupings

International Nuclear Information System (INIS)

Pinover, W.H.; Hanlon, A.L.; Lee, W.R.; Hanks, G.E.

1996-01-01

Purpose: This study demonstrates the correlation of various post-irradiation PSA nadirs with long term biochemical freedom from disease (bNED) survival in patients treated mainly with conformal external beam radiation therapy. It also shows the effects of various groupings of pretreatment (prerx) PSA level, stage, and Gleason score on the rate of achieving a favorable PSA nadir. Materials and Methods: Three hundred forty patients with known pretreatment PSA, >2 years followup treated with radiation alone (278 conformal, 62 conventional) are reported. The median followup is 41 months (range 24 to 96 mos.). Patient grouping by pretreatment PSA levels are <10 ng/ml (143 patients), 10-19.9 ng/ml (108 patients), ≥20 ng/ml (89 patients); by palpation stage are T1C,2AB (240 patients) and T2C,3,4 (100 patients); and by differentiation are Gleason 2-4 (108 patients), Gleason 5-7 (221 patients), Gleason 8-10 (11 patients). The PSA nadir response is given for all patients, and for each of the above prerx groupings. The 5 year actuarial bNED survival is determined for all patients by PSA nadir. Biochemical failure is a PSA ≥1.5 ng/ml and rising on two consecutive measures. Multivariate analysis (MVA) is performed to determine factors predictive of favorable PSA nadir response and predictive of bNED survival. Results: The PSA nadir responses and 5 year bNED survival rates are shown in the table for all patients according to PSA nadir. 66% of patients achieved a favorable nadir (<1.0 ng/ml) which was associated with a 75%-87% 5 year bNED rate, while 34% achieved an unfavorable nadir associated with an 18-32% bNED survival rate at 5 years. The figure illustrates the dramatic separation in outcome associated with the nadir response. The table also illustrates the fraction of patients that achieve various nadir levels subdivided by prerx PSA level, palpation stage and Gleason score. A favorable PSA nadir is obtained in 90%, 63%, and 31% of patients with a prerx PSA <10, 10

A PSA study for the SMART basic design

International Nuclear Information System (INIS)

Han, Sang Hoon; Kim, H. C.; Yang, S. H.; Lee, D. J.

2002-03-01

SMART (System-Integrated Modular Advanced Reactor) is under development that is an advanced integral type small and medium category nuclear power reactor with the rated thermal power of 330 MW. A Probabilistic Safety Analysis (PSA) for the SMART basic design has been performed to evaluate the safety and optimize the design. Currently, the basic design is done and the detailed design is not available for the SMART, we made several assumptions about the system design before performing the PSA. The scope of the PSA was limited to the Level-1 internal full power PSA. The level-2 and 3 PSA, the external PSA, and the low power/shutdown PSA will be performed in the final design stage

Severe accident analysis for level 2 PSA of SMART reactor

Energy Technology Data Exchange (ETDEWEB)

Lee, Jin Yong; Lee, Jeong Hun; Kim, Jong Uk; Yoo, Tae Geun; Chung, Soon Il; Kim, Min Gi [FNC Technology Co., Seoul (Korea, Republic of)

2010-12-15

The objectives of this study are to produce data for level 2 PSA and evaluation results of severe accident by analyzing severe accident sequence of transient events, producing fault tree of containment systems and evaluating direct containment heating of the SMART. In this project, severe accident analysis results were produced for general transient, loss of feedwater, station blackout, and steam line break events, and based on the results, design safety of SMART was verified. Also, direct containment heating phenomenon of the SMART was evaluated using TCE methodology. For level 2 PSA, fault tree of the containment isolation system, reactor cavity flooding system, plant chilled water system, and reactor containment building HVAC system was produced and analyzed

Preliminary Consideration for the Development of Regulatory Level 2 PSA Model

International Nuclear Information System (INIS)

Lee, Chang-Ju

2006-01-01

In order to assess the validity of PSA (probabilistic safety assessment) results and to establish regulatory requirements for relevant safety issues most of the regulators want to develop an independent and convenient risk assessment model including Level 2 PSA area. As this model and framework should be implicitly independent on the licensee's PSA model, it has a primary objective directly for applying to the risk-informed regulatory affairs and for supporting those kinds of works. According this, the regulator can take an objective view for the uncertainty of risk information made by the licensee and keep up the capability and decision-making framework for overall risk assessment results. In addition, the regulatory model may be used to verify and validate the operational risk levels of all engineered safety features of nuclear power plants (NPPs). An issue for plant-specific application of safety goals was previously identified in the US NRC's risk-informed regulatory guidance development activities, and discussed in many Commission papers, e. g. SECY-97-287, which identifies the goal for large early release frequency (LERF). LERF defines a containment performance criteria derived from the quantitative health objectives. As we know, the LERF was chosen to assess risk significance in Regulatory Guide 1.174 (2002) again, which provides one measure of the performance of the containment barrier, and represents a surrogate for early health effects

Correlative study of SPECT bone scan, serum tPSA and fPSA/tPSA ratio and the pathological grade of prostate cancer with bone metastasis

International Nuclear Information System (INIS)

Xu Haiqing; Duan Jun

2011-01-01

Objective: To study the rules and characteristics of SPECT bone scan, serum TPSA, fPSA/tPSA ratio and the pathological grade of prostate cancer with bone metastasis. Methods: Nuclear medicine SPECT bone scan as the gold standard, retrospective analysis of the in vitro radioimmunoassay in 107 patients with prostate cancer serum PSA (prostate specific antigen) levels, serum fPSA/tPSA ratio and whole body bone imaging studies and pathological classification. Results: 107 patients with prostate cancer : 49 patients had bone metastases, accounting for 45.8% (49/107), in which groups of different pathological comparison between the incidence of bone metastasis significantly, the lower the degree of differentiation, the more the incidence of bone metastases high; with elevated levels of tPSA, the incidence of bone metastasis increased significantly; serum tPSA 4 - 40 ng/ml, the use of fPSA/tPSA ratio may improve the diagnostic specificity of prostate cancer. Conclusion: Patients with bone metastases of prostate cancer incidence and degree of differentiation of prostate cancer, serum PSA levels and fPSA/tPSA ratio of a certain relationship. The lower degree of differentiation,the higher the incidence of bone metastasis. (authors)

Quality PSA for PSA applications

International Nuclear Information System (INIS)

Carska, K.; Rybar, J.

2012-03-01

The safety guideline defines with more precision Nuclear Regulatory Authority of the Slovak Republic requirements of the quality of probabilistic safety assessment (PSA) for PSA application. Term of quality of PSA is explained in detail. Procedure for determining the quality of PSA is provided. The categorization of PSA study according the quality of PSA is suggested. A comprehensive list of PSA applications for nuclear facilities is provided. What technical features of a PSA should be satisfied to support the PSA applications of interest is stated. (authors)

Development of the SKI Handbook for reviewing PSA after the review of the of a PSA level 2 study; Utveckling av SKIs Tillsynshandbok foer PSA utifraan granskningen av en PSA Nivaa-2 studie

Energy Technology Data Exchange (ETDEWEB)

Lindholm, Ilona; Sairanen, Risto [VTT Processes, Helsinki (Finland)

2003-02-01

A review of the Oskarshamn 2 Level 2 PSA has been conducted by VTT Processes. One objective of the review was validation and development of Tillsynshandbok PSA applying it to Oskarshamn 2 PSA Level 2 study. The review was based on the PSA Level 2 documentation: the main report, the supporting reports on containment success criteria and release calculations with the MAAP4 code, and five phenomenological reports for selected specific questions. The main result of the phenomenological analyses is that none of the phenomena considered contributes to the conditional failure probability of the Oskarshamn 2 containment in severe accidents. The project was conducted as a set of separate studies and the project quality assurance has also focused on one part at the time. As such, the quality assurance is adequate. A high level QA ensuring that all separate studies and analysis steps use same assumptions seems to be missing. Results from the phenomenology reports are not always transferred to accident analyses and vice versa. There is no specific discussion of uncertainty or sensitivity analyses. In general, the number of sensitivity analyses could be larger. Such should have been provided for sequences or phenomena that could result in early or unmitigated release. Examples are pressure vessel failure at high pressure, the effect of larger hydrogen production, and the key assumptions used for steam explosion and direct containment heating. Suggestions for additional sensitivity studies have been given in discussion of phenomenological reports. The project documentation is generally good. Missing information is usually associated with transfer of results from one study to another. It can be assumed that the information exists also in this cases but has not been documented in the reports above. Documentation of the containment event trees and the assumptions used for them could be more detailed, maybe similar to the approach used in the Appendix of this report. More effort

Development of the SKI Handbook for reviewing PSA after the review of the of a PSA level 2 study

International Nuclear Information System (INIS)

Lindholm, Ilona; Sairanen, Risto

2003-02-01

A review of the Oskarshamn 2 Level 2 PSA has been conducted by VTT Processes. One objective of the review was validation and development of Tillsynshandbok PSA applying it to Oskarshamn 2 PSA Level 2 study. The review was based on the PSA Level 2 documentation: the main report, the supporting reports on containment success criteria and release calculations with the MAAP4 code, and five phenomenological reports for selected specific questions. The main result of the phenomenological analyses is that none of the phenomena considered contributes to the conditional failure probability of the Oskarshamn 2 containment in severe accidents. The project was conducted as a set of separate studies and the project quality assurance has also focused on one part at the time. As such, the quality assurance is adequate. A high level QA ensuring that all separate studies and analysis steps use same assumptions seems to be missing. Results from the phenomenology reports are not always transferred to accident analyses and vice versa. There is no specific discussion of uncertainty or sensitivity analyses. In general, the number of sensitivity analyses could be larger. Such should have been provided for sequences or phenomena that could result in early or unmitigated release. Examples are pressure vessel failure at high pressure, the effect of larger hydrogen production, and the key assumptions used for steam explosion and direct containment heating. Suggestions for additional sensitivity studies have been given in discussion of phenomenological reports. The project documentation is generally good. Missing information is usually associated with transfer of results from one study to another. It can be assumed that the information exists also in this cases but has not been documented in the reports above. Documentation of the containment event trees and the assumptions used for them could be more detailed, maybe similar to the approach used in the Appendix of this report. More effort

PSAPACK 4.2. A code for probabilistic safety assessment level 1. User's manual

International Nuclear Information System (INIS)

1995-01-01

Only limited use has been made until now of the large amount of information contained in probabilistic safety assessments (PSAs). This is mainly due to the complexity of the PSA reports and the difficulties in obtaining intermediate results and in performing updates and recalculations. Moreover, PSA software was developed for mainframe computers, and the files of information such as fault trees and accident sequences were intended for the use of the analysts carrying out PSA studies or other skilled PSA practitioners. The increasing power and availability of personal computers (PCs) and developments in recent years in both hardware and software have made it possible to develop PSA software for use in PCs. Furthermore, the operational characteristics of PCs make them attractive not only for performing PSAs but also for updating the results and in using them in day-to-day applications. The IAEA has therefore developed in co-operation with its Member States, a software package (PSAPACK) for PCs for use in performing a Level 1 PSA and for easy interrogation of the results. Figs

Low percentage of free prostate-specific antigen (PSA) is a strong predictor of later detection of prostate cancer among Japanese men with serum levels of total PSA of 4.0 ng/mL or less.

Science.gov (United States)

Sasaki, Mitsuharu; Ishidoya, Shigeto; Ito, Akihiro; Saito, Hideo; Yamada, Shigeyuki; Mitsuzuka, Koji; Kaiho, Yasuhiro; Shibuya, Daisuke; Yamaguchi, Takuhiro; Arai, Yoichi

2014-11-01

To investigate the effect of the percentage of free prostate-specific antigen (%fPSA) on future prostate cancer risk. We examined serum total PSA (tPSA) and %fPSA annually in a prostate cancer-screening cohort between July 2001 and June 2011. Men with tPSA >4.0 ng/mL or tPSA of 2.0-4.0 ng/mL with %fPSA ≤12% were screened as positive and were recommended to undergo a biopsy. The study population consisted of 6368 men, aged 40-79 years, who had tPSA ≤4.0 ng/mL at initial screening and who subsequently underwent 1 or more screenings. We calculated the cumulative risk and hazard ratio of prostate cancer stratified by the initial %fPSA groups as quartiles of prostate cancer patients. During a median follow-up of 36 months, 119 men were diagnosed with prostate cancer. The lowest quartile of %fPSA (22.2%). For the subset with an initial tPSA ≤1.0 ng/mL, all men diagnosed with cancer had an initial %fPSA ≤33.3% (median). For the subset with tPSA >1.0 ng/mL, men with %fPSA ≤23.0% (median) had significantly higher risk for cancer than those with %fPSA >23.0% (P men with prostate cancer in whom pathologic findings were available, 79 (69.3%) had a Gleason score ≥3 + 4 = 7. A low %fPSA is a strong predictor of a subsequent diagnosis of prostate cancer among men with tPSA levels ≤4.0 ng/mL. Measurement of %fPSA might enhance the detection of high-grade cancer that warrants aggressive treatment. Copyright © 2014 Elsevier Inc. All rights reserved.

Methods and results of a PSA level 2 for a German BWR of the 900 MWe class

International Nuclear Information System (INIS)

Loffler, H.; Sonnenkalb, M.

2006-01-01

On behalf of the federal Ministry for Environment, Nature Conservation and Reactor Safety (BMU) GRS has performed a PSA level 2 for a BWR type 69 NPP of the 900 MWe class, equipped with a N 2 inerted steel containment and a pressure suppression system. Integral deterministic accident analyses have been performed with the computer code MELCOR 1.8.5. Additional analyses have been done for those events and phenomena which are not or not sufficiently covered by MELCOR. The probabilistic event tree analysis begins with the core damage states received from PSA level 1, and it ends with the definition of release categories and the determination of their frequencies. Uncertainties about the frequency of core damage states and about events during the accident progression are taken into account by means of Monte Carlo simulations. If there is a core damage state there is a high probability (>50 %) for a very high and rapid release of radionuclides into the environment. This high conditional probability is due to the very low probability to retain a partly destroyed core inside the reactor pressure vessel (RPV) and because the containment almost certainly fails at the bottom of the control rod drives room after melt release from the failed RPV. (authors)

Research on the improvement of nuclear safety -Development of computing code system for level 3 PSA

Energy Technology Data Exchange (ETDEWEB)

Jeong, Jong Tae; Kim, Dong Ha; Park, Won Seok; Hwang, Mi Jeong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-07-01

Among the various research areas of the level 3 PSA, the effect of terrain on the transport of radioactive material was investigated. These results will give a physical insight in the development of a new dispersion model. A wind tunnel experiment with bell shaped hill model was made in order to develop a new dispersion model. And an improved dispersion model was developed based on the concentration distribution data obtained from the wind tunnel experiment. This model will be added as an option to the atmospheric dispersion code. A stand-alone atmospheric code using MS Visual Basic programming language which runs at the Windows environment of a PC was developed. A user can easily select a necessary data file and type input data by clicking menus, and can select calculation options such building wake, plume rise etc., if necessary. And a user can easily understand the meaning of concentration distribution on the map around the plant site as well as output files. Also the methodologies for the estimation of radiation exposure and for the calculation of risks was established. These methodologies will be used for the development of modules for the radiation exposure and risks respectively. These modules will be developed independently and finally will be combined to the atmospheric dispersion code in order to develop a level 3 PSA code. 30 tabs., 56 figs., refs. (Author).

Research on the improvement of nuclear safety -Development of computing code system for level 3 PSA

International Nuclear Information System (INIS)

Jeong, Jong Tae; Kim, Dong Ha; Park, Won Seok; Hwang, Mi Jeong

1995-07-01

Among the various research areas of the level 3 PSA, the effect of terrain on the transport of radioactive material was investigated. These results will give a physical insight in the development of a new dispersion model. A wind tunnel experiment with bell shaped hill model was made in order to develop a new dispersion model. And an improved dispersion model was developed based on the concentration distribution data obtained from the wind tunnel experiment. This model will be added as an option to the atmospheric dispersion code. A stand-alone atmospheric code using MS Visual Basic programming language which runs at the Windows environment of a PC was developed. A user can easily select a necessary data file and type input data by clicking menus, and can select calculation options such building wake, plume rise etc., if necessary. And a user can easily understand the meaning of concentration distribution on the map around the plant site as well as output files. Also the methodologies for the estimation of radiation exposure and for the calculation of risks was established. These methodologies will be used for the development of modules for the radiation exposure and risks respectively. These modules will be developed independently and finally will be combined to the atmospheric dispersion code in order to develop a level 3 PSA code. 30 tabs., 56 figs., refs. (Author)

Severe accident management at the Loviisa NPP - Application of integrated ROAAM and PSA level 2

International Nuclear Information System (INIS)

Siltanen, S.; Routamo, T.; Tuomisto, H.; Lundstrom, P.

2007-01-01

PSA fault and event tree modelling approaches can be meaningfully applied when statistical reliability data are available (which is the case on level 1), and phenomenological issues are not the dominant source of uncertainty. With PSA studies it is also possible to continuously improve the overall safety by noticing possible weak points and study the influences of planned modifications and design improvements. PSA level 2 is also important because source terms are calculated as the end results, which is not done in the Integrated ROAAM. The source term analysis in PSA level 2 allows us to understand fission product behaviour, which is extremely important when dealing with containment bypass sequences. Source terms can also be directly linked to radioactive release limits set by the Finnish safety authority. Due to ROAAM approach in the SAM strategy it has been possible to simplify the PSA level 2 containment event tree significantly. The usage of ROAAM assures that the phenomenological uncertainties are covered well during this simplification process. (authors)

Correlation of serum androgens and pituitary hormone levels with serum PSA less than 2.5 ng/ml.

Science.gov (United States)

Sofikerim, Mustafa; Oruç, Ozgür; Eskicorapci, Sadettin; Guliyev, Fuat; Ozen, Haluk

2007-07-27

The aim of this clinical study was to determine whether there is a relationship between total serum testosterone, free testosterone, FSH (Follicle-Stimulating Hormone), LH (Luteinizing Hormone) and serum prostate specific antigen (PSA) levels. We postulated that such a correlation existed then the use of hormone specific reference ranges might enhance the usefullness of PSA concentrations 40 years of age visiting our urology outpatient clinics. PSA was correlated to age (r = 0.23, p = 0.019), but there none between serum testosterone and age. No significant correlation was noted between testosterone or free testosterone and serum PSA levels, and none between serum FSH or LH and PSA. In age specific reference groups (41-49; 50-59; 60-69 years), we found no significant correlation between PSA and hormone concentrations. In this population of eugonadal men with serum PSA values less than 2.5 ng/ml, serum androgens and pituitary hormones do not appear to correlate with serum PSA.

Proteolytic Activity of Prostate-Specific Antigen (PSA) towards Protein Substrates and Effect of Peptides Stimulating PSA Activity

Science.gov (United States)

Mattsson, Johanna M.; Ravela, Suvi; Hekim, Can; Jonsson, Magnus; Malm, Johan; Närvänen, Ale; Stenman, Ulf-Håkan; Koistinen, Hannu

2014-01-01

Prostate-specific antigen (PSA or kallikrein-related peptidase-3, KLK3) exerts chymotrypsin-like proteolytic activity. The main biological function of PSA is the liquefaction of the clot formed after ejaculation by cleavage of semenogelins I and II in seminal fluid. PSA also cleaves several other substrates, which may explain its putative functions in prostate cancer and its antiangiogenic activity. We compared the proteolytic efficiency of PSA towards several protein and peptide substrates and studied the effect of peptides stimulating the activity of PSA with these substrates. An endothelial cell tube formation model was used to analyze the effect of PSA-degraded protein fragments on angiogenesis. We showed that PSA degrades semenogelins I and II much more efficiently than other previously identified protein substrates, e.g., fibronectin, galectin-3 and IGFBP-3. We identified nidogen-1 as a new substrate for PSA. Peptides B2 and C4 that stimulate the activity of PSA towards small peptide substrates also enhanced the proteolytic activity of PSA towards protein substrates. Nidogen-1, galectin-3 or their fragments produced by PSA did not have any effect on endothelial cell tube formation. Although PSA cleaves several other protein substrates, in addition to semenogelins, the physiological importance of this activity remains speculative. The PSA levels in prostate are very high, but several other highly active proteases, such as hK2 and trypsin, are also expressed in the prostate and may cleave protein substrates that are weakly cleaved by PSA. PMID:25237904

Decision-making Processes among Prostate Cancer Survivors with Rising PSA Levels: Results from a Qualitative Analysis.

Science.gov (United States)

Shen, Megan Johnson; Nelson, Christian J; Peters, Ellen; Slovin, Susan F; Hall, Simon J; Hall, Matt; Herrera, Phapichaya Chaoprang; Leventhal, Elaine A; Leventhal, Howard; Diefenbach, Michael A

2015-05-01

Prostate cancer survivors with a rising prostate-specific antigen (PSA) level have few treatment options, experience a heightened state of uncertainty about their disease trajectory that might include the possibility of cancer metastasis and death, and often experience elevated levels of distress as they have to deal with a disease they thought they had conquered. Guided by self-regulation theory, the present study examined the cognitive and affective processes involved in shared decision making between physicians and patients who experience a rising PSA after definitive treatment for prostate cancer. In-depth interviews were conducted with 34 prostate cancer survivors who had been diagnosed with a rising PSA (i.e., biochemical failure) within the past 12 months. Survivors were asked about their experiences and affective responses after being diagnosed with a rising PSA and while weighing potential treatment options. In addition, patients were asked about their decision-making process for the initial prostate cancer treatment. Compared with the initial diagnosis, survivors with a rising PSA reported increased negative affect following their diagnosis, concern about the treatability of their disease, increased planning and health behavior change, heightened levels of worry preceding doctor appointments (especially prior to the discussion of PSA testing results), and a strong reliance on physicians' treatment recommendations. Prostate cancer survivors' decision-making processes for the treatment of a rising PSA are markedly different from those of the initial diagnosis of prostate cancer. Because patients experience heightened distress and rely more heavily on their physicians' recommendations with a rising PSA, interactions with the health care provider provide an excellent opportunity to address and assist patients with managing the uncertainty and distress inherent with rising PSA levels. © The Author(s) 2014.

Comparison of global sensitivity analysis techniques and importance measures in PSA

International Nuclear Information System (INIS)

Borgonovo, E.; Apostolakis, G.E.; Tarantola, S.; Saltelli, A.

2003-01-01

This paper discusses application and results of global sensitivity analysis techniques to probabilistic safety assessment (PSA) models, and their comparison to importance measures. This comparison allows one to understand whether PSA elements that are important to the risk, as revealed by importance measures, are also important contributors to the model uncertainty, as revealed by global sensitivity analysis. We show that, due to epistemic dependence, uncertainty and global sensitivity analysis of PSA models must be performed at the parameter level. A difficulty arises, since standard codes produce the calculations at the basic event level. We discuss both the indirect comparison through importance measures computed for basic events, and the direct comparison performed using the differential importance measure and the Fussell-Vesely importance at the parameter level. Results are discussed for the large LLOCA sequence of the advanced test reactor PSA

PSAPACK 4.2. A code for probabilistic safety assessment level 1. User`s manual

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-03-01

Only limited use has been made until now of the large amount of information contained in probabilistic safety assessments (PSAs). This is mainly due to the complexity of the PSA reports and the difficulties in obtaining intermediate results and in performing updates and recalculations. Moreover, PSA software was developed for mainframe computers, and the files of information such as fault trees and accident sequences were intended for the use of the analysts carrying out PSA studies or other skilled PSA practitioners. The increasing power and availability of personal computers (PCs) and developments in recent years in both hardware and software have made it possible to develop PSA software for use in PCs. Furthermore, the operational characteristics of PCs make them attractive not only for performing PSAs but also for updating the results and in using them in day-to-day applications. The IAEA has therefore developed in co-operation with its Member States, a software package (PSAPACK) for PCs for use in performing a Level 1 PSA and for easy interrogation of the results. Figs.

The diagnostic value of PSA, cPSA and bone scintigraphy for early skeletal metastasis of prostate cancer

International Nuclear Information System (INIS)

Xue Zhongguang

2007-01-01

Objective: To evaluate the value of prostate specific antigen (PSA), complexed prostate specific antigen (cPSA) and bone scintigraphic imaging in diagnosis of early skeletal metastasis of prostate cancer. Methods: 152 patients (74 with prostate cancer, 78 with benign prostate disease) and 90 controls were examined for the serum concentrations of PSA and cPSA. At the same time, the 74 patients with PCa were examined with bone scintigraphy. The cPSA/PSA ratio was calculated. Results: Serum PSA, cPSA levels and cPSA/PSA ratio of patients with prostate cancer were significantly higher than those in benign prostate patients and controls. In addition, the serum PSA, cPSA levels and cPSA/PSA ratio in prostate cancer patients with skeletal metastasis were remarkably higher than those in patients without skeletal metastasis, and the differences were significant (P 20 μg/L, cPSA>10 μg/L, cPSA/PSA>0.80, there is a high probability that skeletal metastasis of prostate cancer would be present and bone scintigraphy should be performed. (authors)

Approach to development and use of PSA Level 2 analysis for the Cernavoda nuclear power plant

International Nuclear Information System (INIS)

Turcu, I.; Deaconu, R.; Radu, G.

1998-01-01

This paper first describes the status of PSA activities for the Cernavoda NPP and the extension of the PSA work to include Level 2 PSA. Important characteristics of this reactor type for Level 2 PSA are outlined. Due to the specific layout of the CANDU reactor the evolution of severe accidents is considerably different to vessel type LWRs. Accidents can be roughly categorized into three categories, ''''severe accidents'''' which lead to the loss of core structural integrity, delayed loss of core structural integrity as a consequence of the loss of heat sinks, and fuel channel failures. The current work for modelling accident progression in the core region is described. The elements for the Level 2 PSA including definition of PDSs, probabilistic containment logic and source term calculation are outlined. It is pointed out that uncertainties have to be considered which are contained in the models to bridge knowledge gaps. For this purpose sensitivity studies will be carried out for key modelling assumptions. (author)

Attributes of Full Scope Level 1 Probabilistic Safety Assessment (PSA) for Applications in Nuclear Power Plants

International Nuclear Information System (INIS)

2016-10-01

This publication supersedes IAEA-TECDOC-1511, Determining the Quality of Probabilistic Safety Assessment (PSA) for Applications in Nuclear Power Plants (published in 2006), which provided detailed information on technical features of a restricted scope PSA aimed at analysing only internal initiating events caused by random component failures and human errors, and accident sequences that may lead to reactor core damage during operation. The present publication extends the scope of the PSA to cover a broader range of internal and external hazards, and low power and shutdown modes of nuclear power plant operation. In addition, some PSA aspects relevant to lessons learned from the accident at the Fukushima Daiichi nuclear power plant are also considered

Proteolytic activity of prostate-specific antigen (PSA towards protein substrates and effect of peptides stimulating PSA activity.

Directory of Open Access Journals (Sweden)

Johanna M Mattsson

Full Text Available Prostate-specific antigen (PSA or kallikrein-related peptidase-3, KLK3 exerts chymotrypsin-like proteolytic activity. The main biological function of PSA is the liquefaction of the clot formed after ejaculation by cleavage of semenogelins I and II in seminal fluid. PSA also cleaves several other substrates, which may explain its putative functions in prostate cancer and its antiangiogenic activity. We compared the proteolytic efficiency of PSA towards several protein and peptide substrates and studied the effect of peptides stimulating the activity of PSA with these substrates. An endothelial cell tube formation model was used to analyze the effect of PSA-degraded protein fragments on angiogenesis. We showed that PSA degrades semenogelins I and II much more efficiently than other previously identified protein substrates, e.g., fibronectin, galectin-3 and IGFBP-3. We identified nidogen-1 as a new substrate for PSA. Peptides B2 and C4 that stimulate the activity of PSA towards small peptide substrates also enhanced the proteolytic activity of PSA towards protein substrates. Nidogen-1, galectin-3 or their fragments produced by PSA did not have any effect on endothelial cell tube formation. Although PSA cleaves several other protein substrates, in addition to semenogelins, the physiological importance of this activity remains speculative. The PSA levels in prostate are very high, but several other highly active proteases, such as hK2 and trypsin, are also expressed in the prostate and may cleave protein substrates that are weakly cleaved by PSA.

Treatment of the loss of ultimate heat sink initiating events in the IRSN level 1 PSA

International Nuclear Information System (INIS)

Dupuy, Patricia; Georgescu, Gabriel; Corenwinder, Francois

2014-01-01

The total loss of the ultimate heat sink is an initiating event which, even it is mainly of external origin, has been considered in the frame of internal events Level 1 PSA by IRSN. The on-going actions on the development of external hazards PSA and the recent incident of loss of the heat sink induced by the ingress of vegetable matter that occurred in France in 2009 have pointed out the need to improve the modeling of the loss of the heat sink initiating event and sequences to better take into account the fact that this loss may be induced by external hazards and thus affect all the site units. The paper presents the historical steps of the modeling of the total loss of the heat sink, the safety stakes of this modeling, the main assumptions used by IRSN in the associated PSA for the 900 MWe reactors and the results obtained. The total loss of the heat sink was not initially addressed in the safety demonstration of French NPPs. On the basis of the insights of the first probabilistic assessments performed in the 80's, the risks associated to this 'multiple failure situation' turned out to be very significant and design and organisational improvements were implemented on the plants. Reviews of the characterization of external hazards and of their consequences on the installations and French operating feedback have revealed that extreme hazards may induce a total loss of the heat sink. Moreover, the accident that occurred at Fukushima in 2011 has pointed out the risk of such a loss of long duration at all site units in case of extreme hazards. In this context, it seems relevant to further improve the modelling of the total loss of the heat sink by considering the external hazards that may cause this loss. In a first step, IRSN has improved the assumptions and data used in the loss of the heat sink PSA model, in particular by considering that such a loss may affect all the site units. The next challenge will be the deeper analysis of the impact of external hazards on

Plasma carotenoids and tocopherols in relation to prostate-specific antigen (PSA) levels among men with biochemical recurrence of prostate cancer.

Science.gov (United States)

Antwi, Samuel O; Steck, Susan E; Zhang, Hongmei; Stumm, Lareissa; Zhang, Jiajia; Hurley, Thomas G; Hebert, James R

2015-10-01

Although men presenting with clinically localized prostate cancer (PrCA) often are treated with radical prostatectomy or radiation therapy with curative intent, about 25-40% develop biochemically recurrent PrCA within 5 years of treatment, which has no known cure. Studies suggest that carotenoid and tocopherol intake may be associated with PrCA risk and progression. We examined plasma carotenoid and tocopherol levels in relation to prostate-specific antigen (PSA) levels among men with PSA-defined biochemical recurrence of PrCA. Data analyzed were from a 6-month diet, physical activity and stress-reduction intervention trial conducted in South Carolina among biochemically recurrent PrCA patients (n=39). Plasma carotenoids and tocopherol levels were measured using high-performance liquid chromatography (HPLC). Linear regression was used to estimate least-square means comparing PSA levels of men with high versus low carotenoid/tocopherol levels, adjusting for covariates. After adjusting for baseline PSA level, plasma cis-lutein/zeaxanthin level at 3 months was related inversely to PSA level at 3 months (P=0.0008), while α-tocopherol (P=0.01), β-cryptoxanthin (P=0.01), and all-trans-lycopene (P=0.004) levels at 3 months were related inversely to PSA levels at 6-months. Percent increase in α-tocopherol and trans-β-carotene levels from baseline to month 3 were associated with lower PSA levels at 3 and 6 months. Percent increase in β-cryptoxanthin, cis-lutein/zeaxanthin and all-trans-lycopene were associated with lower PSA levels at 6 months only. Certain plasma carotenoids and tocopherols were related inversely to PSA levels at various timepoints, suggesting that greater intake of foods containing these micronutrients might be beneficial to men with PSA-defined PrCA recurrence. Copyright © 2015. Published by Elsevier Ltd.

Risk Metrics and Measures for an Extended PSA

International Nuclear Information System (INIS)

Wielenberg, A.; Loeffler, H.; Hasnaoui, C.; Burgazzi, L.; Cazzoli, E.; Jan, P.; La Rovere, S.; Siklossy, T.; Vitazkova, J.; Raimond, E.

2016-01-01

This report provides a review of the main used risk measures for Level 1 and Level 2 PSA. It depicts their advantages, limitations and disadvantages and develops some more precise risk measures relevant for extended PSAs and helpful for decision-making. This report does not recommend or suggest any quantitative value for the risk measures. It does not discuss in details decision-making based on PSA results neither. The choice of one appropriate risk measure or a set of risk measures depends on the decision making approach as well as on the issue to be decided. The general approach for decision making aims at a multi-attribute approach. This can include the use of several risk measures as appropriate. Section 5 provides some recommendations on the main risk metrics to be used for an extended PSA. For Level 1 PSA, Fuel Damage Frequency and Radionuclide Mobilization Frequency are recommended. For Level 2 PSA, the characterization of loss of containment function and a total risk measure based on the aggregated activity releases of all sequences rated by their frequencies is proposed. (authors)

SERIAL PERCENT-FREE PSA IN COMBINATION WITH PSA FOR POPULATION-BASED EARLY DETECTION OF PROSTATE CANCER

Science.gov (United States)

Ankerst, Donna Pauler; Gelfond, Jonathan; Goros, Martin; Herrera, Jesus; Strobl, Andreas; Thompson, Ian M.; Hernandez, Javier; Leach, Robin J.

2016-01-01

PURPOSE To characterize the diagnostic properties of serial percent-free prostate-specific antigen (PSA) in relation to PSA in a multi-ethnic, multi-racial cohort of healthy men. MATERIALS AND METHODS 6,982 percent-free PSA and PSA measures were obtained from participants in a 12 year+ Texas screening study comprising 1625 men who never underwent biopsy, 497 who underwent one or more biopsies negative for prostate cancer, and 61 diagnosed with prostate cancer. Area underneath the receiver-operating-characteristic-curve (AUC) for percent-free PSA, and the proportion of patients with fluctuating values across multiple visits were determined according to two thresholds (under 15% versus 25%) were evaluated. The proportion of cancer cases where percent-free PSA indicated a positive test before PSA > 4 ng/mL did and the number of negative biopsies that would have been spared by percent-free PSA testing negative were computed. RESULTS Percent-free PSA fluctuated around its threshold of PSA tested positive earlier than PSA in 71.4% (34.2%) of cancer cases, and among men with multiple negative biopsies and a PSA > 4 ng/mL, percent-free PSA would have tested negative in 31.6% (65.8%) instances. CONCLUSIONS Percent-free PSA should accompany PSA testing in order to potentially spare unnecessary biopsies or detect cancer earlier. When near the threshold, both tests should be repeated due to commonly observed fluctuation. PMID:26979652

PSA Review Handbook

International Nuclear Information System (INIS)

Hallman, Anders; Nyman, Ralph; Knochenhauer, Michael

2004-05-01

The Swedish Nuclear Power Inspectorate (SKI) expresses requirements on the performance of PSAs as well as on PSA activities in general in the the regulatory document 'Regulations Concerning Safety in Certain Nuclear Facilities', SKlFS 1998:1. The follow-up of these activities is part of the inspection tasks of the SKI. In view or this, there is a need for documented guidelines on now to perform these inspections and reviews. The SKI PSA Review Handbook is intended to be a support in the SKI inspection and control of the PSA activities or the licensees. These PSA activities include both the organisation and working procedures of the licensee, the layout and contents of the PSA, and its areas of application. Using the regulation SKIFS 1998:1 as a starting point, the review handbook presents important aspects to be considered when judging whether a licensee fulfils the requirements on PSA activities, including the performance of PSA:s or PSA applications. The handbook shall also be a guidance for the review of PSA:s. However, the intention of the PSA Review Handbook is not to be a handbook for how a PSA is performed. The PSA Review Handbook is applicable to all types or initiating events and all operating conditions, and has been structured in a way, which stresses the integrated characteristics of PSA in the creation of the risk picture of a plant. The PSA Review Handbook has been based on the requirements for PSA of nuclear power plants, as this is the most extensive application. However, the relevant parts of it are also applicable when analysing other nuclear installations. The PSA Review Handbook is published as a research report as its contents are judged to be of general interest, and the SKI welcomes comments to the handbook. An update or the PSA Review Handbook may be required as experience with the use of the handbook is acquired and if general PSA requirements change

PET/CT with (18)F-choline after radical prostatectomy in patients with PSA ≤2 ng/ml. Can PSA velocity and PSA doubling time help in patient selection?

Science.gov (United States)

Chiaravalloti, Agostino; Di Biagio, Daniele; Tavolozza, Mario; Calabria, Ferdinando; Schillaci, Orazio

2016-07-01

To investigate the performance of (18)F-fluorocholine ((18)F-FCH) PET/CT in relation to the prostate-specific antigen (PSA) kinetic indexes, PSA doubling time (PSAdt) and PSA velocity (PSAve), in detecting recurrent prostate cancer (PC) in a selected population of patients treated with radical prostatectomy and with PSA ≤2 ng/ml. The study group comprised 79 patients (mean age 70 ± 7 years, range 58 - 77 years) who had been treated with radical surgery 30 to 90 months previously and with biochemical failure (defined as a measurable serum PSA level) who were evaluated with (18)F-FCH PET/CT. In order to establish the optimal threshold for PSAdt and PSAve, the diagnostic performance of PSA, PSAdt and PSAve were compared by receiver operating characteristic analysis. In the population examined, PSA (mean ± SD) was 1.37 ± 0.44 ng/ml (range 0.21 - 2 ng/ml) before PET/CT examination, PSAdt was 10.04 ± 16.67 months and PSAve was 2.75 ± 3.11 ng/ml per year. (18)F-FCH PET/CT was positive in 44 patients (55 %). PSAve and PSAdt were significantly different between patients with a positive and a negative (18)F-FCH PET/CT scan. Thresholds of 6 months for PSAdt and 1 ng/ml per year for PSAve were selected. For PSAdt ≤6 months the detection rate (DR) was 65 %, and for PSAve >1 ng/ml per year the DR was 67 %. PSA values were not significantly different between patients with a positive and a negative PET/CT scan. The results of our study suggest that (18)F-FCH PET/CT could be considered for the evaluation of patients with biochemical recurrence of PC and with low PSA levels. Fast PSA kinetics could be useful in the selection of these patients.

PSA in design of passive/active safety reactors

International Nuclear Information System (INIS)

Sato, T.; Tanabe, A.; Kondo, S.

1995-01-01

PSAs in the design of advanced reactors are applied mainly in level 1 PSA areas. However, even in level 1 PSA, there are certain areas where special care must be taken depending on plant design concepts. This paper identifies these areas both for passive and active safety reactor concepts. For example, 'long-term PSA' and shutdown PSA are very important for a passive safety reactor concept from the standpoint of effectiveness of a grace period and passive safety systems. External events are also important for an active safety reactor concept. These kinds of special PSAs are difficult to conduct precisely in a conceptual design stage. This paper shows methods of conducting these kinds of special PSAs simply and conveniently and the use of acquired insights for the design of advanced reactors. This paper also clarifies the meaning or definition of a grace period from the standpoint of PSA

Time to PSA rise differentiates the PSA bounce after HDR and LDR brachytherapy of prostate cancer.

Science.gov (United States)

Burchardt, Wojciech; Skowronek, Janusz

2018-02-01

To investigate the differences in prostate-specific antigen (PSA) bounce (PB) after high-dose-rate (HDR-BT) or low-dose-rate (LDR-BT) brachytherapy alone in prostate cancer patients. Ninety-four patients with localized prostate cancer (T1-T2cN0), age ranged 50-81 years, were treated with brachytherapy alone between 2008 and 2010. Patients were diagnosed with adenocarcinoma, Gleason score ≤ 7. The LDR-BT total dose was 144-145 Gy, in HDR-BT - 3 fractions of 10.5 or 15 Gy. The initial PSA level (iPSA) was assessed before treatment, then PSA was rated every 3 months over the first 2 years, and every 6 months during the next 3 years. Median follow-up was 3.0 years. Mean iPSA was 7.8 ng/ml. In 58 cases, PSA decreased gradually without PB or biochemical failure (BF). In 24% of patients, PB was observed. In 23 cases (24%), PB was observed using 0.2 ng/ml definition; in 10 cases (11%), BF was diagnosed using nadir + 2 ng/ml definition. The HDR-BT and LDR-BT techniques were not associated with higher level of PB (26 vs. 22%, p = 0.497). Time to the first PSA rise finished with PB was significantly shorter after HDR-BT then after LDR-BT (median, 10.5 vs. 18.0 months) during follow-up. Predictors for PB were observed only after HDR-BT. Androgen deprivation therapy (ADT) and higher Gleason score decreased the risk of PB (HR = 0.11, p = 0.03; HR = 0.51, p = 0.01). The higher PSA nadir and longer time to PSA nadir increased the risk of PB (HR 3.46, p = 0.02; HR 1.04, p = 0.04). There was no predictors for PB after LDR-BT. HDR-BT and LDR-BT for low and intermediate risk prostate cancer had similar PB rate. The PB occurred earlier after HDR-BT than after LDR-BT. ADT and higher Gleason score decreased, and higher PSA nadir and longer time to PSA nadir increased the risk of PB after HDR-BT.

Radiometric assays for the measurement of PSA

International Nuclear Information System (INIS)

Venkatesh, M.

1997-01-01

Prostate Specific Antigen, a serine protease enzyme, of M.W. ∼ 26-33 kDa, is widely considered to be a very useful marker for prostate cancer. It satisfies nearly all the requirements of an ideal 'Tumour Marker' and has hence attracted a lot of attention in the past decade. PSA is present in multiple forms in serum, with an appreciable fraction bound to the protease inhibitor α-1-antichymotrypsin (ACT) and to a small extent to other proteins such as α-2-macroglobulin (AMG) leaving the rest in the free form. The total PSA levels have been reported to have 80% sensitivity and 60% specificity towards the detection of prostate cancer. The lack of specificity occurs mainly due to the high levels of t-PSA in benign prostatic hypertrophy(BPH) apart from the cancer. The concept of free PSA has been introduced in the recent past and the ratio of free/total PSA levels have been shown to be advantageous in the differential diagnosis of BPH from prostate cancer. The f/t ratio is considered to be particularly useful in the grey zones of decision making (t-PSA levels 4-20 ng/mL). The need for the development of assays for total and free PSA is felt due to: a. the high incidence of prostate cancers being detected currently; b. the high cost of tests (higher for free PSA assay, and the cost becomes an important parameter when a patient has to be regularly monitored after therapy) that is not affordable for many patients; c. the potential for research in the area of prostate cancer management where the PSA (total and free) assays will be of great help

Performance indicators at Embalse NPP: PSA and safety system indicators based on PSA models

International Nuclear Information System (INIS)

Fornero, D.A.

2001-01-01

Several indicators have been implemented at Embalse NPP. The objective was selecting some representative parameters to evaluate the performance of both the plant and the personnel activities, important for safety. A first set of indicators was defined in accordance with plant technical staff criteria. A complementary set of them was addressed later based on WANO guidance. This report presents the set of indicators used at Embalse NPP, centering the description to related to safety systems performance indicators (SSPI). Some considerations are done about the calculation methods, the need for aligning and updating their values following Embalse Probabilistic Safety Assessment (PSA) development, and some pros and cons of using the PSA model for getting systems indicators. Owing to the fact that PSA ownership by utilities is also a subject of the meeting, some characteristics of the organization of the PSA Project are described at the beginning of the report. At Embalse NPP a Level 1 PSA has been developed under the responsibility of its own plant and with an important contribution from the IAEA. PSA was developed at the site, conducting this to a study strongly interactive with the station staff. (author)

Development of computing code system for level 3 PSA

International Nuclear Information System (INIS)

Jeong, Jong Tae; Yu, Dong Han; Kim, Seung Hwan.

1997-07-01

Among the various research areas of the level 3 PSA, the effect of terrain on the transport of radioactive material was investigated through wind tunnel experiment. These results will give a physical insight in the development of a new dispersion model. Because there are some discrepancies between the results from Gaussian plume model and those from field test, the effect of terrain on the atmospheric dispersion was investigated by using CTDMPLUS code. Through this study we find that the model which can treat terrain effect is essential in the atmospheric dispersion of radioactive materials and the CTDMPLUS model can be used as a useful tool. And it is suggested that modification of a model and experimental study should be made through the continuous effort. The health effect assessment near the Yonggwang site by using IPE (Individual plant examination) results and its site data was performed. The health effect assessment is an important part of consequence analysis of a nuclear power plant site. The MACCS was used in the assessment. Based on the calculation of CCDF for each risk measure, it is shown that CCDF has a slow slope and thus wide probability distribution in cases of early fatality, early injury, total early fatality risk, and total weighted early fatality risk. And in cases of cancer fatality and population dose within 48km and 80km, the CCDF curve have a steep slope and thus narrow probability distribution. The establishment of methodologies for necessary models for consequence analysis resulting form a server accident in the nuclear power plant was made and a program for consequence analysis was developed. The models include atmospheric transport and diffusion, calculation of exposure doses for various pathways, and assessment of health effects and associated risks. Finally, the economic impact resulting form an accident in a nuclear power plant was investigated. In this study, estimation models for each cost terms that considered in economic

Development of computing code system for level 3 PSA

Energy Technology Data Exchange (ETDEWEB)

Jeong, Jong Tae; Yu, Dong Han; Kim, Seung Hwan

1997-07-01

Among the various research areas of the level 3 PSA, the effect of terrain on the transport of radioactive material was investigated through wind tunnel experiment. These results will give a physical insight in the development of a new dispersion model. Because there are some discrepancies between the results from Gaussian plume model and those from field test, the effect of terrain on the atmospheric dispersion was investigated by using CTDMPLUS code. Through this study we find that the model which can treat terrain effect is essential in the atmospheric dispersion of radioactive materials and the CTDMPLUS model can be used as a useful tool. And it is suggested that modification of a model and experimental study should be made through the continuous effort. The health effect assessment near the Yonggwang site by using IPE (Individual plant examination) results and its site data was performed. The health effect assessment is an important part of consequence analysis of a nuclear power plant site. The MACCS was used in the assessment. Based on the calculation of CCDF for each risk measure, it is shown that CCDF has a slow slope and thus wide probability distribution in cases of early fatality, early injury, total early fatality risk, and total weighted early fatality risk. And in cases of cancer fatality and population dose within 48km and 80km, the CCDF curve have a steep slope and thus narrow probability distribution. The establishment of methodologies for necessary models for consequence analysis resulting form a server accident in the nuclear power plant was made and a program for consequence analysis was developed. The models include atmospheric transport and diffusion, calculation of exposure doses for various pathways, and assessment of health effects and associated risks. Finally, the economic impact resulting form an accident in a nuclear power plant was investigated. In this study, estimation models for each cost terms that considered in economic

PSA Update Procedures, an Ultimate Need for Living PSA

International Nuclear Information System (INIS)

Hegedus, D.

1998-01-01

Nuclear facilities by their complex nature, change with time. These changes can be both physical (plant modification, etc.), operational (enhanced procedures, etc.) and organizational. In addition, there are also changes in our understanding of the plant, due to operational experience, data collection, technology enhancements, etc. Therefore, it is imperative that PSA model must be frequently up-dated or modified to reflect these changes. Over the last ten years. these has been a remarkable growth of the use of Probabilistic Safety Assessments (PSAs). The most rapidly growing area of the PSA Applications is their use to support operational decision-making. Many of these applications are characterized by the potential for not only improving the safety level but also for providing guidance on the optimal use of resources and reducing regulatory burden. To enable a wider use of the PSA model as a tool for safety activities it is essential to maintain the model in a controlled state. Moreover, to fulfill requirements for L iving PSA , the PSA model has to be constantly updated and/or monitored to reflect the current plant configuration. It should be noted that the PSA model should not only represent the plant design but should also represent the operational and emergency procedures. To keep the PSA model up-to-date several issues should be clearly defined including: - Responsibility should be divided among the PSA group, - Procedures for implementing changes should be established, and - QA requirements/program should be established to assure documentation and reporting. (author)

Development and perspectives of PSA in Cuba

International Nuclear Information System (INIS)

1996-01-01

During the last decade the GDA/PSA has carried out the pre-operational PSA task for the Juragua Nuclear Power Plant. Since 1991 the work has been accomplished in the frames of the IAEA Technical Assistance Project CUB/9/008. The paper describes the stages of this study, (concluding with the Final Report of the pre-operational Level 1 PSA Rev. O), its assumptions, limitations and the main results and concluding remarks

Experience in PSA fault tree modularization at the ASCO NPP

International Nuclear Information System (INIS)

Nos Llorens, V.; Frances Urmeneta, M.; Fraig Sureda, J.

1995-01-01

Probabilistic Safety Analysis (PSA) is a basic tool in decision-making for the optimization of back fittings, procedures and maintenance practices. ASCO NPP PSA was developed with a high level of detail in the models. This required considerable computer resources (long running time) to carry out the quantification. The quantification time had therefore to be flexible to allow continuous evaluation of the impact on the estimation and reduction of risk in the plant, and also to facilitate post-PSA applications. The most suitable way of achieving this flexibility was by compacting and reducing the detailed fault trees of the project by means of a modularization process. The purpose of the paper is to present the practical experience acquired with modularization carried out in the UTE UNITEC-INYPSA-EMPRESARIOS AGRUPADOS framework and the method applied, the support computer programs devised and their degree of effectiveness. (Author)

Study of possibility using LANL PSA-methodology for accident probability RBMK researches

International Nuclear Information System (INIS)

Petrin, S.V.; Yuferev, V.Y.; Zlobin, A.M.

1995-01-01

The reactor facility probabilistic safety analysis methodologies are considered which are used at U.S. LANL and RF NIKIET. The methodologies are compared in order to reveal their similarity and differences, determine possibilities of using the LANL technique for RBMK type reactor safety analysis. It is found that at the PSA-1 level the methodologies practically do not differ. At LANL the PHA, HAZOP hazards analysis methods are used for more complete specification of the accounted initial event list which can be also useful at performance of PSA for RBMK. Exchange of information regarding the methodology of detection of dependent faults and consideration of human factor impact on reactor safety is reasonable. It is accepted as useful to make a comparative study result analysis for test problems or PSA fragments using various computer programs employed at NIKIET and LANL

Correlation between bone scan findings and serum PSA level in prostate cancer patients in Bangladesh: both newly diagnosed and hormonally treated cases

International Nuclear Information System (INIS)

Yasmeen, S.; Nasreen, F.; Kabir, M.F.

2007-01-01

Full text: The objective of the current study was to determine whether pre- treatment serum prostate specific antigen (PSA) levels can identify a group with low probability of osseous metastases and safely eliminate the need for bone scan as a routine part of the staging evaluation in Bangladeshi patients with newly diagnosed prostate carcinoma. Also, to find out a cut off value for serum PSA level for predicting positive bone scan in newly diagnosed Bangladeshi prostate cancer patients and to assess the role of PSA level in hormonally treated cases. Prostate cancer most commonly metastasizes to the bone. Bone scintigraphy is one of the best methods in detecting bone metastases, assessing the progression of the disease and response to therapy. For more than 30 yrs it has been known that bone scintigraphy is more sensitive than radiographic, clinical evaluation or chemical markers such as alkaline phosphatase or acid phosphatase in detection of early osseous metastatic prostate cancer. The introduction of PSA has dramatically changed the management of prostate cancer. Serum PSA level has proven to be a useful serum marker for detection of metastatic prostate cancer and it provides the best overall correlation. It also has considerable impact on bone scanning. Of special significance is the fact that patients who have a low PSA level in previously untreated carcinoma of prostate are extremely unlikely to have positive findings on a bone scan for metastases. The picture is different in patients who has received and responded to hormonal therapy. Bone scintigraphy appears to be extremely useful in patients whose PSA level begins to rise after surgical procedure. Patients, who were on anti- androgen therapy, even though they had visible metastatic disease on bone scans, had normal level of PSA Patients and methods: A total of 390 cases were studied. Some (n=242) were newly diagnosed without having any specific treatment other than surgery. Others (n=148) were old cases

The value of multimodality imaging in the investigation of a PSA recurrence after radical prostatectomy in the Irish hospital setting.

Science.gov (United States)

McLoughlin, L C; Inder, S; Moran, D; O'Rourke, C; Manecksha, R P; Lynch, T H

2018-02-01

The diagnostic evaluation of a PSA recurrence after RP in the Irish hospital setting involves multimodality imaging with MRI, CT, and bone scanning, despite the low diagnostic yield from imaging at low PSA levels. We aim to investigate the value of multimodality imaging in PC patients after RP with a PSA recurrence. Forty-eight patients with a PSA recurrence after RP who underwent multimodality imaging were evaluated. Demographic data, postoperative PSA levels, and imaging studies performed at those levels were evaluated. Eight (21%) MRIs, 6 (33%) CTs, and 4 (9%) bone scans had PCa-specific findings. Three (12%) patients had a positive MRI with a PSA PSA ≥1.1 ng/ml (p = 0.05). Zero patient had a positive CT TAP at a PSA level PSA levels PSA levels PSA levels ≥1.1 ng/ml. MRI alone is of investigative value at PSA <1.0 ng/ml. The indication for CT, MRI, or isotope bone scanning should be carefully correlated with the clinical question and how it will affect further management.

Development of a fully-coupled, all atates, all hazards level 2 PSA at leibstadt nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Zvoncek, Pavol; Nusbaumer, Olivier [Safety Compliance and Technical Support Department, Leibstadt Nuclear Power Plant, Leibstadt (Sweden); Torri, Alfred [Risk Management Associates, Inc., Encinitas (United States)

2017-03-15

This paper describes the development process, the innovative techniques used and insights gained from the latest integrated, full scope, multistate Level 2 PSA analysis conducted at the Leibstadt Nuclear Power Plant (KKL), Switzerland. KKL is a modern single-unit General Electric Boiling Water Reactor (BWR/6) with Mark III Containment, and a power output of 3600MWth/1200MWe, the highest among the five operating reactors in Switzerland. A Level 2 Probabilistic Safety Assessment (PSA) analyses accident phenomena in nuclear power plants, identifies ways in which radioactive releases from plants can occur and estimates release pathways, magnitude and frequency. This paper attempts to give an overview of the advanced modeling techniques that have been developed and implemented for the recent KKL Level 2 PSA update, with the aim of systematizing the analysis and modeling processes, as well as complying with the relatively prescriptive Swiss requirements for PSA. The analysis provides significant insights into the absolute and relative importance of risk contributors and accident prevention and mitigation measures. Thanks to several newly developed techniques and an integrated approach, the KKL Level 2 PSA report exhibits a high degree of reviewability and maintainability, and transparently highlights the most important risk contributors to Large Early Release Frequency (LERF) with respect to initiating events, components, operator actions or seismic component failure probabilities (fragilities)

Living PSA program for VVER 440/213 in the Czech Republic

International Nuclear Information System (INIS)

Husak, S.; Patrik, M.

2000-01-01

The paper presents an overview of a Living PSA concept in the Czech Republic for the VVER 440/213 NPP Dukovany unit. The first step of PSA program was a Level 1 basic study for Unit No. 1 which was completed in 1995. The main objective of the study was to determine the risk level of full power operation and its contributors as well as to reveal the weak points of the plant. Living PSA program for a Level 1 study has been afterwards established as a framework for all activities related to risk assessment and risk based decision-making support in NPP Dukovany. The basic parts of the project are: a management of PSA models and studies to implement design and procedures, modifications or new data inputs from data collection; continuous improvement based of new analyses, experiments or more detailed models; an extensions of the scope (external events, all plant operating modes, other sources of radioactive releases). The Living PSA program in NPP Dukovany provides basis for three kinds of PSA activities: risk assessment applications, risk monitoring and risk assessment of operational. (author)

Evaluating the Phoenix definition of biochemical failure after (125)I prostate brachytherapy: Can PSA kinetics distinguish PSA failures from PSA bounces?

Science.gov (United States)

Thompson, Anna; Keyes, Mira; Pickles, Tom; Palma, David; Moravan, Veronika; Spadinger, Ingrid; Lapointe, Vincent; Morris, W James

2010-10-01

To evaluate the prostate-specific antigen (PSA) kinetics of PSA failure (PSAf) and PSA bounce (PSAb) after permanent (125)I prostate brachytherapy (PB). The study included 1,006 consecutive low and "low tier" intermediate-risk patients treated with (125)I PB, with a potential minimum follow-up of 4 years. Patients who met the Phoenix definition of biochemical failure (nadir + 2 ng/mL(-1)) were identified. If the PSA subsequently fell to ≤0.5 ng/mL(-1)without intervention, this was considered a PSAb. All others were scored as true PSAf. Patient, tumor and dosimetric characteristics were compared between groups using the chi-square test and analysis of variance to evaluate factors associated with PSAf or PSAb. Median follow-up was 54 months. Of the 1,006 men, 57 patients triggered the Phoenix definition of PSA failure, 32 (56%) were true PSAf, and 25 PSAb (44%). The median time to trigger nadir + 2 was 20.6 months (range, 6-36) vs. 49 mo (range, 12-83) for PSAb vs. PSAf groups (p < 0.001). The PSAb patients were significantly younger (p < 0.0001), had shorter time to reach the nadir (median 6 vs. 11.5 months, p = 0.001) and had a shorter PSA doubling time (p = 0.05). Men younger than age 70 who trigger nadir +2 PSA failure within 38 months of implant have an 80% likelihood of having PSAb and 20% chance of PSAf. With adequate follow-up, 44% of PSA failures by the Phoenix definition in our cohort were found to be benign PSA bounces. Our study reinforces the need for adequate follow-up when reporting PB PSA outcomes, to ensure accurate estimates of treatment efficacy and to avoid unnecessary secondary interventions. 2010. Published by Elsevier Inc. All rights reserved.

Evaluating the Phoenix Definition of Biochemical Failure After 125I Prostate Brachytherapy: Can PSA Kinetics Distinguish PSA Failures From PSA Bounces?

International Nuclear Information System (INIS)

Thompson, Anna; Keyes, Mira; Pickles, Tom

2010-01-01

Purpose: To evaluate the prostate-specific antigen (PSA) kinetics of PSA failure (PSAf) and PSA bounce (PSAb) after permanent 125 I prostate brachytherapy (PB). Methods and Materials: The study included 1,006 consecutive low and 'low tier' intermediate-risk patients treated with 125 I PB, with a potential minimum follow-up of 4 years. Patients who met the Phoenix definition of biochemical failure (nadir + 2 ng/mL -1 ) were identified. If the PSA subsequently fell to ≤0.5 ng/mL -1 without intervention, this was considered a PSAb. All others were scored as true PSAf. Patient, tumor and dosimetric characteristics were compared between groups using the chi-square test and analysis of variance to evaluate factors associated with PSAf or PSAb. Results: Median follow-up was 54 months. Of the 1,006 men, 57 patients triggered the Phoenix definition of PSA failure, 32 (56%) were true PSAf, and 25 PSAb (44%). The median time to trigger nadir + 2 was 20.6 months (range, 6-36) vs. 49 mo (range, 12-83) for PSAb vs. PSAf groups (p < 0.001). The PSAb patients were significantly younger (p < 0.0001), had shorter time to reach the nadir (median 6 vs. 11.5 months, p = 0.001) and had a shorter PSA doubling time (p = 0.05). Men younger than age 70 who trigger nadir +2 PSA failure within 38 months of implant have an 80% likelihood of having PSAb and 20% chance of PSAf. Conclusions: With adequate follow-up, 44% of PSA failures by the Phoenix definition in our cohort were found to be benign PSA bounces. Our study reinforces the need for adequate follow-up when reporting PB PSA outcomes, to ensure accurate estimates of treatment efficacy and to avoid unnecessary secondary interventions.

Multiple external hazards compound level 3 PSA methods research of nuclear power plant

Science.gov (United States)

Wang, Handing; Liang, Xiaoyu; Zhang, Xiaoming; Yang, Jianfeng; Liu, Weidong; Lei, Dina

2017-01-01

2011 Fukushima nuclear power plant severe accident was caused by both earthquake and tsunami, which results in large amount of radioactive nuclides release. That accident has caused the radioactive contamination on the surrounding environment. Although this accident probability is extremely small, once such an accident happens that is likely to release a lot of radioactive materials into the environment, and cause radiation contamination. Therefore, studying accidents consequences is important and essential to improve nuclear power plant design and management. Level 3 PSA methods of nuclear power plant can be used to analyze radiological consequences, and quantify risk to the public health effects around nuclear power plants. Based on multiple external hazards compound level 3 PSA methods studies of nuclear power plant, and the description of the multiple external hazards compound level 3 PSA technology roadmap and important technical elements, as well as taking a coastal nuclear power plant as the reference site, we analyzed the impact of off-site consequences of nuclear power plant severe accidents caused by multiple external hazards. At last we discussed the impact of off-site consequences probabilistic risk studies and its applications under multiple external hazards compound conditions, and explained feasibility and reasonableness of emergency plans implementation.

Seismic PSA method for multiple nuclear power plants in a site

Energy Technology Data Exchange (ETDEWEB)

Hakata, Tadakuni [Nuclear Safety Commission, Tokyo (Japan)

2007-07-15

The maximum number of nuclear power plants in a site is eight and about 50% of power plants are built in sites with three or more plants in the world. Such nuclear sites have potential risks of simultaneous multiple plant damages especially at external events. Seismic probabilistic safety assessment method (Level-1 PSA) for multi-unit sites with up to 9 units has been developed. The models include Fault-tree linked Monte Carlo computation, taking into consideration multivariate correlations of components and systems from partial to complete, inside and across units. The models were programmed as a computer program CORAL reef. Sample analysis and sensitivity studies were performed to verify the models and algorithms and to understand some of risk insights and risk metrics, such as site core damage frequency (CDF per site-year) for multiple reactor plants. This study will contribute to realistic state of art seismic PSA, taking consideration of multiple reactor power plants, and to enhancement of seismic safety. (author)

High-Risk Prostate Cancer With Gleason Score 8–10 and PSA Level ≤15 ng/ mL Treated With Permanent Interstitial Brachytherapy

International Nuclear Information System (INIS)

Fang, L. Christine; Merrick, Gregory S.; Butler, Wayne M.; Galbreath, Robert W.; Murray, Brian C.; Reed, Joshua L.; Adamovich, Edward; Wallner, Kent E.

2011-01-01

Purpose: With widespread prostate-specific antigen (PSA) screening, there has been an increase in men diagnosed with high-risk prostate cancer defined by a Gleason score (GS) ≥8 coupled with a relatively low PSA level. The optimal management of these patients has not been defined. Cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) were evaluated in brachytherapy patients with a GS ≥8 and a PSA level ≤15 ng/mL with or without androgen-deprivation therapy (ADT). Methods and Materials: From April 1995 to October 2005, 174 patients with GS ≥8 and a PSA level ≤15 ng/mL underwent permanent interstitial brachytherapy. Of the patients, 159 (91%) received supplemental external beam radiation, and 113 (64.9%) received ADT. The median follow-up was 6.6 years. The median postimplant Day 0 minimum percentage of the dose covering 90% of the target volume was 121.1% of prescription dose. Biochemical control was defined as a PSA level ≤0.40 ng/mL after nadir. Multiple parameters were evaluated for impact on survival. Results: Ten-year outcomes for patients without and with ADT were 95.2% and 92.5%, respectively, for CSS (p = 0.562); 86.5% and 92.6%, respectively, for bPFS (p = 0.204); and 75.2% and 66.0%, respectively, for OS (p = 0.179). The median post-treatment PSA level for biochemically controlled patients was <0.02 ng/mL. Multivariate analysis failed to identify any predictors for CSS, whereas bPFS and OS were most closely related to patient age. Conclusions: Patients with GS ≥8 and PSA level ≤15 ng/mL have excellent bPFS and CSS after brachytherapy with supplemental external beam radiotherapy. The use of ADT did not significantly impact bPFS, CSS, or OS.

PSA bounce phenomenon after transperineal interstitial permanent prostate brachytherapy for localized prostate cancer

International Nuclear Information System (INIS)

Morita, Masashi; Lederer, J.L.; Fukagai, Takashi; Yoshida, Hideki; Shimada, Makoto

2004-01-01

We described the temporarily increase phenomenon in prostate-specific antigen level (PSA bounce) after transperineal interstitial permanent prostate brachytherapy (TIPPB) for localized prostate cancer. From December 1998 to May 2003, 500 consecutive patients with localized prostate cancer were treated with TIPPB using iodine-125 or palladium-103. We examined 200 patients who have more than 2-year PSA follow-up. Median follow-up length was 1,069 days (range, 712-1,411 days). No patient received neoadjuvant or adjuvant hormone therapy. PSA determinations were performed every 3 months for the first 2 years after procedure, and every 6 months hereafter. PSA bounce was defined as an increase of 0.1 ng/ml or greater above the preceding PSA level after implant followed by a subsequent decrease below that level. The American Society for Therapeutic Radiology and Oncology (ASTRO) consensus panel criteria 1996 were used to define biochemical failure. PSA bounce was observed in 40% (80/200) of the cases receiving TIPPB. The median time to PSA bounce was 13 months from the day of implant. The median magnitude of the PSA bounce was 0.3 ng/ml from the pre-bounce level. Twelve cases demonstrated biochemical failure according to the ASTRO consensus guidelines of three consecutive rises in PSA. Ten of these subsequently showed a drop in PSA, consistent with biologic control of their disease. Two cases remain classified as apparent biochemical failures. A transient rise in the PSA following TIPPB, the so-called ''bounce'' is a common occurrence. The apparent PSA control of ten of twelve cases failing by the ASTRO criteria raises some concern. Further observation will be necessary to determine ways to discriminate these from true disease progression. (author)

Regulatory aspects of the use of PSA to evaluate technical specifications

International Nuclear Information System (INIS)

Rumpf, J.

1991-01-01

Based on experiences gained in PSA activities the regulatory body of the GDR initiated a programme to investigate the feasibility of using PSA for the evaluation of technical specifications. This programme is just under work. In addition, to improve PSA, the GDR takes part in a programme which is aimed at performing plant specific level 1, PSA as well as and which enables operating organizations to carry out PSA on their own. The most important of some preliminary general findings presented in this paper are: - Technical specifications form a well established envelope of operational conditions and procedures. A total re-evaluation is not considered necessary; Probabilistic evaluation of technical specifications should be an integrated part of PSA activities (at least level 1). Single assessment is not considered reasonable; Probabilistic evaluation of technical specifications has to be based on plant specific information and realistic accident sequence calculations; Up to now no quantitative probabilistic criteria for technical specifications have been established. (author)

Living PSA issues in France on pressurized water reactors

International Nuclear Information System (INIS)

Dewailly, J.; Deriot, S.; Dubreuil Chambardel, A.; Francois, P.; Magne, L.

1993-09-01

Two Probabilistic Safety Assessments (PSAs) carried out in France on 900 and 1300 MWe Pressurized Water Reactor units ended in 1990. These PSAs determined the core damage frequency for all plant operating conditions ranging from cold shutdown for refuelling to full power operation. Since 1990, these PSAs have been used increasingly as tools for applications such as accident precursor analysis, risk-based Technical Specifications, and maintenance optimization. In turn, these applications are used to enhance the initial PSAs. The notion of a ''living'' PSA which can be used and updated is slowly taking form. The accident precursor analysis consists in applying PSA event trees to obtain quick information on the potential consequences of a precursor event and on the corresponding probabilities of occurrence. A feedback on PSAs is provided by comparing them with actual operating incidents. The computation of the allowed outage time during power operation, based on the computerized models of Probabilistic Safety Assessments, requires adjustments: calculation of hourly risk of core damage under different reactor conditions without equipment unavailabilities. The proposed method also turns out to be an aid in determining the safe shutdown condition and procedure. Furthermore, when introducing a sufficient level of detail, PSA reliability models make it possible to compute contributions and to perform sensitivity studies in order to highlight those components for which a maintenance effort should be made. From the experience acquired up to now, there was felt to be a strong need to create guidelines for using PSAs that would simplify their implementation by the experts in charge of determining Technical Specifications, of maintenance programs, etc. who are not generally specialists in PSAs. For this purpose, it is necessary to improve the intelligibility of the models made in order for them to be used and to offer user's guides adapted to each application. Documents

Level-1 probability safety assessment of the Iranian heavy water reactor using SAPHIRE software

International Nuclear Information System (INIS)

Faghihi, F.; Ramezani, E.; Yousefpour, F.; Mirvakili, S.M.

2008-01-01

The main goal of this review paper is to analyze the total frequency of the core damage of the Iranian Heavy Water Research Reactor (IHWRR) compared with standard criteria and to determine the strengths and the weaknesses of the reactor safety systems towards improving its design and operation. The PSA has been considered for full-power state of the reactor and this article represents a level-1 PSA analysis using System Analysis Programs for Hands-On Integrated Reliability Evaluations (SAPHIRE) software. It is specifically designed to permit a listing of the potential accident sequences, compute their frequencies of occurrence and assign each sequence to a consequence. The method used for modeling the systems and accident sequences, is Large Fault Tree/Small Event Tree method. This PSA level-1 for IHWRR indicates that, based on conservative assumptions, the total frequency of accidents that would lead to core damage from internal initiating events is 4.44E-05 per year of reactor operation

Level-1 probability safety assessment of the Iranian heavy water reactor using SAPHIRE software

Energy Technology Data Exchange (ETDEWEB)

Faghihi, F. [Department of Nuclear Engineering, School of Engineering, Shiraz University, 71348-51153 Shiraz (Iran, Islamic Republic of); Research Center for Radiation Protection, Shiraz University, Shiraz (Iran, Islamic Republic of); Nuclear Safety Research Center, Shiraz University, Shiraz (Iran, Islamic Republic of)], E-mail: faghihif@shirazu.ac.ir; Ramezani, E. [Department of Nuclear Engineering, School of Engineering, Shiraz University, 71348-51153 Shiraz (Iran, Islamic Republic of); Yousefpour, F. [Atomic Energy Organization of Iran (AEOI), Tehran (Iran, Islamic Republic of); Mirvakili, S.M. [Department of Nuclear Engineering, School of Engineering, Shiraz University, 71348-51153 Shiraz (Iran, Islamic Republic of)

2008-10-15

The main goal of this review paper is to analyze the total frequency of the core damage of the Iranian Heavy Water Research Reactor (IHWRR) compared with standard criteria and to determine the strengths and the weaknesses of the reactor safety systems towards improving its design and operation. The PSA has been considered for full-power state of the reactor and this article represents a level-1 PSA analysis using System Analysis Programs for Hands-On Integrated Reliability Evaluations (SAPHIRE) software. It is specifically designed to permit a listing of the potential accident sequences, compute their frequencies of occurrence and assign each sequence to a consequence. The method used for modeling the systems and accident sequences, is Large Fault Tree/Small Event Tree method. This PSA level-1 for IHWRR indicates that, based on conservative assumptions, the total frequency of accidents that would lead to core damage from internal initiating events is 4.44E-05 per year of reactor operation.

Clinical performance of serum [-2]proPSA derivatives, %p2PSA and PHI, in the detection and management of prostate cancer

OpenAIRE

Huang, Ya-Qiang; Sun, Tong; Zhong, Wei-De; Wu, Chin-Lee

2014-01-01

Prostate-specific antigen (PSA) has been widely used as a serum marker for prostate cancer (PCa) screening or progression monitoring, which dramatically increased rate of early detection while significantly reduced PCa-specific mortality. However, a number of limitations of PSA have been noticed. Low specificity of PSA may lead to overtreatment in men who presenting with a total PSA (tPSA) level of < 10 ng/mL. As a type of free PSA (fPSA), [-2]proPSA is differentially expressed in peripheral ...

The percentage of prostate-specific antigen (PSA) isoform [-2]proPSA and the Prostate Health Index improve the diagnostic accuracy for clinically relevant prostate cancer at initial and repeat biopsy compared with total PSA and percentage free PSA in men aged ≤65 years.

Science.gov (United States)

Boegemann, Martin; Stephan, Carsten; Cammann, Henning; Vincendeau, Sébastien; Houlgatte, Alain; Jung, Klaus; Blanchet, Jean-Sebastien; Semjonow, Axel

2016-01-01

To prospectively test the diagnostic accuracy of the percentage of prostate specific antigen (PSA) isoform [-2]proPSA (%p2PSA) and the Prostate Health Index (PHI), and to determine their role for discrimination between significant and insignificant prostate cancer at initial and repeat prostate biopsy in men aged ≤65 years. The diagnostic performance of %p2PSA and PHI were evaluated in a multicentre study. In all, 769 men aged ≤65 years scheduled for initial or repeat prostate biopsy were recruited in four sites based on a total PSA (t-PSA) level of 1.6-8.0 ng/mL World Health Organization (WHO) calibrated (2-10 ng/mL Hybritech-calibrated). Serum samples were measured for the concentration of t-PSA, free PSA (f-PSA) and p2PSA with Beckman Coulter immunoassays on Access-2 or DxI800 instruments. PHI was calculated as (p2PSA/f-PSA × √t-PSA). Uni- and multivariable logistic regression models and an artificial neural network (ANN) were complemented by decision curve analysis (DCA). In univariate analysis %p2PSA and PHI were the best predictors of prostate cancer detection in all patients (area under the curve [AUC] 0.72 and 0.73, respectively), at initial (AUC 0.67 and 0.69) and repeat biopsy (AUC 0.74 and 0.74). t-PSA and %f-PSA performed less accurately for all patients (AUC 0.54 and 0.62). For detection of significant prostate cancer (based on Prostate Cancer Research International Active Surveillance [PRIAS] criteria) the %p2PSA and PHI equally demonstrated best performance (AUC 0.70 and 0.73) compared with t-PSA and %f-PSA (AUC 0.54 and 0.59). In multivariate analysis PHI we added to a base model of age, prostate volume, digital rectal examination, t-PSA and %f-PSA. PHI was strongest in predicting prostate cancer in all patients, at initial and repeat biopsy and for significant prostate cancer (AUC 0.73, 0.68, 0.78 and 0.72, respectively). In DCA for all patients the ANN showed the broadest threshold probability and best net benefit. PHI as single parameter

The open PSA standard as a framework for migration of probabilistic models. Experiences with the KKB PSA

International Nuclear Information System (INIS)

Becker, G.; Hussels, U.; Epstein, S.; Rauzy, A.; Schubert, B.

2008-01-01

In its present state, the open PSA standard is helpful to determine capabilities of PSA approaches, which have been taken into account by those who formulated it. As soon, as tools come up, which can automatically bring a given PSA into the standard form, the data will be accessible by other software tools, which either are supplementary to the original one, or they may act in the context of quality control. Taking into account, that a PSA model represents a value of some two to ten person years (dependent on level of completeness and level of detail), it is important to have the data in a transparent way, which does not depend on proprietary formats, and can thus be used for more purposes than those, which are implemented in given PSA codes. (orig.)

Generation of risk importance information from severe accident PSA model

International Nuclear Information System (INIS)

Seo, Mi Ro; Kim, Hyeong Taek; Moon, Chan Kook

2012-01-01

One of the important objects conducting Probabilistic Safety Assessment (PSA) is the relative evaluation of importance of the component or function that is greatly affected to the plant safety. This evaluation is performed by the importance assessment methods such as Risk Reduction Worth, Risk Achievement Worth, and Fuss el Vessley method from the aspect of core damage frequency (CDF). In the Level 1 PSA model, the importance of each component can be evaluated since the CDF is calculated by the combination of the branch probability of event tree and the component failure probability in the fault tree. But, the Level 2 PSA model in order to assess the containment integrity cannot evaluate the risk importance by the above methods because the model is consisted of 3 parts, plant damage status, containment event tree, and source term category. So, in the field that the Level 2 PSA risk importance information should be reflected, such as maintenance rule program, risk importance has been determined by the subjective judgment of the model developer. This study was performed in order to generate the risk importance information more objectively and systematically in the Level 2 PSA model, focused on the containment event tree in the domain PHWR Level 2 PSA model

Predictor of response to salvage radiotherapy in patients with PSA recurrence after radical prostatectomy. The usefulness of PSA doubling time

International Nuclear Information System (INIS)

Numata, Kousaku; Azuma, Koji; Hashine, Katsuyoshi; Sumiyoshi, Yoshiteru

2005-01-01

We assessed predictors of response to salvage radiotherapy (sRT) in patients with prostate-specific antigen (PSA) recurrence after radical prostatectomy. A total of 21 patients receiving sRT for PSA recurrence without systemic progression after radical prostatectomy had medical records available for retrospective review. We defined sRT as external beam radiotherapy for patients with a continuous increase in PSA level≥0.2 ng/ml after radical prostatectomy. Response was defined as achievement of a PSA nadir of ≤0.1 ng/ml. Various pre-treatment parameters were evaluated retrospectively. The median follow-up period after sRT was 38 months. Of the 21 patients, 15 were good responders (71%). The only predictive factor was PSA doubling time (PSADT). Age and PSA level at diagnosis, Gleason score and surgical margin status were not significant predictors of response. The median PSADT in responders was 6.2 months versus 1.9 months in non-responders (P=0.019). The patients with a PSADT of ≥5 months were all responders. PSADT appears to be a good predictor of response to sRT. sRT was especially effective when PSADT was ≥5 months. (author)

Comparative Study on Atmospheric Dispersion Module of Level 3 PSA

Energy Technology Data Exchange (ETDEWEB)

Kwon, Dahye; Jang, Misuk; Kang, Hyun Sik; Kim, Seoung Rae [NESS, Daejeon (Korea, Republic of)

2016-10-15

Some regulation documents such as Regulatory Guides and NUREG publications from the U.S. Nuclear Regulatory Commission (NRC) have influences on domestic radiation environmental analyses. As renewal versions of NUREG-0800 and NUREG-1555 have issued lately, the assessment for Severe Accident (SA) with Probabilistic Safety Assessment (PSA) should be added to Safety Analysis Report (SAR) and Radiation Environmental Report (RER). Because these reports are the required documents for obtaining the construction permit and operating license, it is important to understand the PSA methodology and it needs to improve the site-specific input data of L3PSA codes for SA. First, our review focuses on the atmospheric dispersion and deposition related input data of L3PSA code in this paper. Then we will continue to review the improvements of other input data. Two atmospheric dispersion models, which are PAVAN developed for design basis accident and ATMOS of MACCS2 code developed for SA, were reviewed in this paper. L3PSA deals with the effects of severe accidents and basically includes the evaluation of both short- and long-term effects. Therefore, both the deposition effects and nuclide information(type, amount, and chemical characteristics of released radionuclide) would be considered as the input parameters of atmospheric dispersion model for L3PSA. Additionally, the meteorological data would be sampled randomly to meet the purpose of probabilistic method. However, the sampling method would be selected according to analysis purpose. After review, ATMOS module and its input data are suitably developed for the atmospheric dispersion analysis of L3PSA. However, ATMOS module was developed using the site-specific terrain and environment characteristics. For the domestic application, it needs to study the input data reflecting the Korean terrain and environment characteristics. It would be also continuously improved in response to the time- and site-specific changes of weather

Determining if pretreatment PSA doubling time predicts PSA trajectories after radiation therapy for localized prostate cancer

International Nuclear Information System (INIS)

Soto, Daniel E.; Andridge, Rebecca R.; Pan, Charlie C.; Williams, Scott G.; Taylor, Jeremy M.G.; Sandler, Howard M.

2009-01-01

Introduction: To determine if pretreatment PSA doubling time (PSA-DT) can predict post-radiation therapy (RT) PSA trajectories for localized prostate cancer. Materials and methods: Three hundred and seventy-five prostate cancer patients treated with external beam RT without androgen deprivation therapy (ADT) were identified with an adequate number of PSA values. We utilized a linear mixed model (LMM) analysis to model longitudinal PSA data sets after definitive treatment. Post-treatment PSA trajectories were allowed to depend on the pre-RT PSA-DT, pre-RT PSA (iPSA), Gleason score (GS), and T-stage. Results: Pre-RT PSA-DT had a borderline impact on predicting the rate of PSA rise after nadir (p = 0.08). For a typical low risk patient (T1, GS ≤ 6, iPSA 10), the predicted PSA-DT post-nadir was 21% shorter for pre-RT PSA-DT 24 month (19 month vs. 24 month). Additional significant predictors of post-RT PSA rate of rise included GS (p < 0.0001), iPSA (p < 0.0001), and T-stage (p = 0.02). Conclusions: We observed a trend between rapidly rising pre-RT PSA and the post-RT post-nadir PSA rise. This effect appeared to be independent of iPSA, GS, or T-stage. The results presented suggest that pretreatment PSA-DT may help predict post-RT PSA trajectories

Radiographic progression with nonrising PSA in metastatic castration-resistant prostate cancer: post hoc analysis of PREVAIL.

Science.gov (United States)

Bryce, A H; Alumkal, J J; Armstrong, A; Higano, C S; Iversen, P; Sternberg, C N; Rathkopf, D; Loriot, Y; de Bono, J; Tombal, B; Abhyankar, S; Lin, P; Krivoshik, A; Phung, D; Beer, T M

2017-06-01

Advanced prostate cancer is a phenotypically diverse disease that evolves through multiple clinical courses. PSA level is the most widely used parameter for disease monitoring, but it has well-recognized limitations. Unlike in clinical trials, in practice, clinicians may rely on PSA monitoring alone to determine disease status on therapy. This approach has not been adequately tested. Chemotherapy-naive asymptomatic or mildly symptomatic men (n=872) with metastatic castration-resistant prostate cancer (mCRPC) who were treated with the androgen receptor inhibitor enzalutamide in the PREVAIL study were analyzed post hoc for rising versus nonrising PSA (empirically defined as >1.05 vs ⩽1.05 times the PSA level from 3 months earlier) at the time of radiographic progression. Clinical characteristics and disease outcomes were compared between the rising and nonrising PSA groups. Of 265 PREVAIL patients with radiographic progression and evaluable PSA levels on the enzalutamide arm, nearly one-quarter had a nonrising PSA. Median progression-free survival in this cohort was 8.3 months versus 11.1 months in the rising PSA cohort (hazard ratio 1.68; 95% confidence interval 1.26-2.23); overall survival was similar between the two groups, although less than half of patients in either group were still at risk at 24 months. Baseline clinical characteristics of the two groups were similar. Non-rising PSA at radiographic progression is a common phenomenon in mCRPC patients treated with enzalutamide. As restaging in advanced prostate cancer patients is often guided by increases in PSA levels, our results demonstrate that disease progression on enzalutamide can occur without rising PSA levels. Therefore, a disease monitoring strategy that includes imaging not entirely reliant on serial serum PSA measurement may more accurately identify disease progression.

African-American (AA) men with local-regional prostate cancer (PC) present with higher prostate specific antigen (PSA) levels than whites: results of RTOG 94-12

International Nuclear Information System (INIS)

Vijayakumar, S.; Winter, K.; Sause, W.; Gallagher, M.J.; Perez, C.; Bondy, M.

1996-01-01

Purpose/Objective: To use pretreatment serum PSA levels as an 20), gleason score (2-5,6-7,7-10), race (whites and AAs), and two interactions viz (a) PSA by race (p=0.0012) and (b) PSA by total gleason score (p=0.0001). When race was replaced by educational status, or income, or both, the fits (0.8246,0.8197, and 0.7815, respectively) were not as good as the fit with race in the model. Conclusion: The findings of this nation-wide prospective registration study with a high percentage of AA patient participation confirms previous, smaller, geographically-limited studies (1,2,3) results that AA patients with non-metastatic PC present with a higher mean PSA values than whites. The multivariate findings imply that, for each level of total gleason score, there is a higher percentage of whites with PSA levels 20. Education and/or income as surrogates of sociological status could not completely explain the racial differences. Other reasons for health-care barriers among AAs need to be identified

Complement of existing ASAMPSA2 guidance for Level 2 PSA for shutdown states of reactors, Spent Fuel Pool and recent R and D results

International Nuclear Information System (INIS)

Kumar, M.; Olsson, A.; Loeffler, H.; Morandi, S.; Gumenyuk, D.; Dejardin, P.; Yu, S.; Jan, P.; Kubicek, J.; Serrano, C.; Raimond, E.; Dirksen, G.; Ivanov, I.; Groudev, P.; Kowal, K.; Prosek, Andrej; Nitoi, M.; Vitazkova, J.; Hirata, K.; Burgazzi, L.

2016-01-01

impact, size of rooms on the path etc. In any case the impact of very hot gas and of hydrogen has to be considered. The dependencies between reactor accident and SFP management appear to be an important issue for L2 PSA risk assessment. The report provides information on ongoing R and D activities which may support the preparation of guidelines for 'traditional' and extended L2 PSA. In addition, a list is provided for those topics which seem to have inadequate covering in present activities. Appendices cover the level 1 shutdown states PSA and country-specific examples related to shutdown PSA and spent fuel pool PSA from ASAMPSA-E WP40 contributing organizations. (authors)

Antigenic determinants of prostate-specific antigen (PSA) and development of assays specific for different forms of PSA.

OpenAIRE

Nilsson, O.; Peter, A.; Andersson, I.; Nilsson, K.; Grundstr?m, B.; Karlsson, B.

1997-01-01

Monoclonal antibodies were raised against prostate-specific antigen (PSA) by immunization with purified free PSA, i.e. not in complex with any protease inhibitor (F-PSA) and PSA in complex with alpha1-anti-chymotrypsin (PSA-ACT). Epitope mapping of PSA using the established monoclonal antibody revealed a complex pattern of independent and partly overlapping antigenic domains in the PSA molecule. Four independent antigenic domains and at least three partly overlapping domains were exposed both...

Diagnostic value of serum free PSA and the ratio of free to total PSA in the diagnosis of prostate cancer

International Nuclear Information System (INIS)

Qiu Ningyan; Zhang Jingxin; Wu Jinchang; Gong Yiming; Li Huiping

2005-01-01

In order to evaluate the value of free prostate specific antigen (FPSA) and F/T PSA ratio in differential diagnosis of benign prostate hyperplasia (BPH) from prostate cancer (PC), serum FPSA and TPSA levels were measured in 85 patients with PC, 97 BPH and 89 healthy volunteers by chemiluminescence enzyme immunoassay (CLEIA), and the ratio of F/T PSA was calculated. The results showed that serum FPSA and TPSA levels were increased in healthy volunteers of 41-88 years old and were significantly higher in healthy volunteers of 61-88 years old than that in 20-40 gear old (P 10.0 μg/L were 65.0%, 30.9% and 4.1%, respectively, while they were 5.9%, 20.0% and 74.1% in PC patients (P<0.01). When the TPSA value was between 4.0-10.0 μg/L and the ratio of F/T PSA was at 0.10 and below, the probability of PC was larger(88.9%). But the ratio of F/T PSA was at 0.25 and above, the probability of PC was smaller(6.20%). Serum FPSA and TPSA both increased with age in healthy volunteers of 41-88 years old and were positively correlated with age. There were about 30.9% of BPH and 20.0% of PC patients with overlapping of TPSA level. Our conclusion is that the F/T PSA ratio can significantly enhance the specificity for PC diagnosis, especially when the TPSA is within the diagnostic gray zone. (authors)

Perspectives of Living PSA in NPP Krsko

International Nuclear Information System (INIS)

Vrbanic, I.; Kastelan, M.

1996-01-01

Nuclear power plant Krsko has completed the Level 1/Level 2 Probabilistic Safety Analysis (PSA) for internal initiating events and is in the process of completing the same for the external initiators. The analysis completed up to now has provided a valuable insight into a plant risk profile. In NPP Krsko there is a plan to use the PSA model as a permanent tool for the risk based applications and incorporate it into a decision making process. In order to achieve this there is a need to permanently maintain the PSA model in a manner that it reflects both the plan configuration/design at a time point and the operational experience up to the time point. All the activities aimed toward keeping the PSA model up-to-dated in this sense are usually referred to as a Living PSA (LPSA) program. NPP Krsko is in the process of defining and proceduralizing a LPSA program that would be plant specific and based on known world practices. Further, in order to be suitable for risk based applications the PSA model must be flexible in a sense that modifications to the base case model may be done easily and requantifications performed quickly as to evaluate various conditions imposed by real or hypothetical situations. NPP Krsko PSA model has been based on licensing type software. The requirements specified above dictate the transfer of the overall model to an application oriented software of newer generation with larger capabilities. The transfer becomes a part of a mentioned ongoing effort aimed at establishing LPSA model and concept. The paper present this effort and the perspectives of LPSA concept and risk based applications in NPP Krsko. (author)

Serum PSA and cure perspective for prostate cancer in males with nonpalpable tumor

Directory of Open Access Journals (Sweden)

Marcos F. Dall'Oglio

2005-10-01

Full Text Available INTRODUCTION: Many studies have shown the association between PSA levels and the subsequent detection of prostate cancer. In the present trial, we have studied the relationship between preoperative PSA levels and clinical outcome following radical prostatectomy in men with clinical stage T1c. MATERIALS AND METHODS: 257 individuals with clinical stage T1c undergoing retropubic radical prostatectomy were selected in the period from 1991 to 2000. Following surgery, biochemical recurrence-free survival curves were constructed according to PSA levels between 0-4; 4.1-10; 10.1-20 and > 20 ng/mL. RESULTS: Of the total of 257 selected patients, 206 (80% had Gleason scores from 2 to 6 and 51 (20%, presented Gleason scores 7 and 8, as defined by the pathological report from prostate biopsy. There was no biochemical recurrence of disease when the PSA was lower than 4, regardless of Gleason score. Biochemical recurrence-free survival according to PSA between 0-4; 4.1-10; 10.1-20 and > 20 was 100%, 87.6%, 79% and 68.8% for Gleason scores 2-6 and 100%; 79.4%; 40% and 100% for Gleason scores 7-8 respectively. When all individuals were grouped, regardless of their Gleason scores, the probability of biochemical recurrence-free survival was 100%, 65.1%, 53.4% and 72.2% according to PSA between 0-4; 4.1-10; 10.1-20 and > 20 ng/mL respectively. CONCLUSION: Non-palpable prostate cancer presents higher chances of cure when the PSA is inferior to 4 ng/mL.

DIAGNOSTIC AND PROGNOSTIC UTILITY OF SERUM PSA IN BREAST CANCER

Institute of Scientific and Technical Information of China (English)

张淑群; 强水云; 李妙羡; 纪宗正

2004-01-01

Objective To investigate the diagnostic and prognostic value of total and free prostate-specific antigen (PSA) in breast cancer women. Methods Using the microparticle enzyme immunoassay system, we measured the concentrations of these markers in the sera of 85 women with breast cancer and in 30 healthy women.Results Free PSA levels were significantly higher in women with breast cancer than healthy women (P ＜0. 05 ).The percentage of free PSA predominant subjects was 37. 6% in breast cancer patients and 3. 3% in healthy women.In women with breast cancer,total PSA positivity was 23.5% and free PSA positivity was 27. 1%. When compared to negatives,total PSA positive patients had a higher percentage of lymph node involvement tamours ( P ＞0. 05).However, patients with predominant free PSA had a higher percentage of early stage than patients with predominant PSA-ACT. Conclusion This study indicate clinical significance of preoperative measurement of serum total and free PSA in diagnosis and prognosis of women with breast cancer. The expression of KLKs is correlated with carcinogenesis of breast cancer.

Evaluation of postradiotherapy PSA patterns and correlation with 10-year disease free survival outcomes for prostate cancer

International Nuclear Information System (INIS)

Zelefsky, Michael J.; Ben-Porat, Leah; Chan, Heather M.; Fearn, Paul A.; Venkatraman, Ennapadam S.

2006-01-01

Purpose: To describe the prostate-specific antigen (PSA) pattern profiles observed after external beam radiotherapy with and without short-term neoadjuvant androgen deprivation therapy (ST-ADT) and to report the association of established posttreatment PSA patterns with long-term disease-free survival outcomes. Methods and Materials: A total of 1,665 patients were treated with conformal external beam radiotherapy for clinically localized prostate cancer. Of 570 patients who had the requisite >10 consecutive PSA measurements for statistical analysis, 194 patients received a median of 3 months of ADT before radiotherapy and 376 were treated with radiotherapy alone. The median follow up was 103 months. Results: In the group treated with ST-ADT, three distinct postradiotherapy PSA patterns were identified: a stable trend (44%), an increasing trend followed by stabilization of the PSA (25%), and an increasing trend (31%). Among the subgroup that demonstrated a rising and subsequent stabilizing patterns, PSA levels had gradually risen to a median value of 0.9 ng/mL after therapy, stabilized, and remained durably suppressed. The only identified trends among patients treated with external beam radiotherapy without ST-ADT were declining PSA levels followed by stable PSA trends or declining patterns followed by rising levels. Patients whose PSA levels stabilized after an initial rise or those with slowly rising PSA profiles had a lower incidence of distant metastasis compared to those with accelerated rises after therapy. Conclusions: For those treated with external beam radiotherapy in conjunction with ST-ADT, a significant percentage who develop a rising PSA after treatment are expected to manifest subsequent stabilization at plateaued levels of approximately 1.0 ng/mL, which can remain durably suppressed. The likelihood of distant metastasis in these patients is low despite the PSA stabilization at levels 1.0 ng/mL or higher and comparable to outcomes observed for those

Workshop on PSA for New and Advanced Reactors

International Nuclear Information System (INIS)

2012-01-01

This workshop was organized by the NEA Working Group on Risk Assessment (WGRISK). The key objective of the workshop was to share the current state-of-the art on the PSA (Probabilistic Safety Assessment) applied for new reactors and advanced reactors. Fifty experts from 13 countries and one international organization (IAEA) participated in the present workshop, and 35 technical papers were presented. The main topics of interest, discussed during the workshop, included the followings: regulatory aspects, risk-informed methods, technical aspects of the PSA for new and advanced reactors, hazards of PSA (internal and external), severe accident/source term/Level 2 PSA, and consequence analysis/Level 3 PSA. Among the technical aspects of the PSA, the assessment of the reliability of passive safety systems appears to be a recurrent issue

PSA Model Improvement Using Maintenance Rule Function Mapping

Energy Technology Data Exchange (ETDEWEB)

Seo, Mi Ro [KHNP-CRI, Nuclear Safety Laboratory, Daejeon (Korea, Republic of)

2011-10-15

The Maintenance Rule (MR) program, in nature, is a performance-based program. Therefore, the risk information derived from the Probabilistic Safety Assessment model is introduced into the MR program during the Safety Significance determination and Performance Criteria selection processes. However, this process also facilitates the determination of the vulnerabilities in currently utilized PSA models and offers means of improving them. To find vulnerabilities in an existing PSA model, an initial review determines whether the safety-related MR functions are included in the PSA model. Because safety-related MR functions are related to accident prevention and mitigation, it is generally necessary for them to be included in the PSA model. In the process of determining the safety significance of each functions, quantitative risk importance levels are determined through a process known as PSA model basic event mapping to MR functions. During this process, it is common for some inadequate and overlooked models to be uncovered. In this paper, the PSA model and the MR program of Wolsong Unit 1 were used as references

Development and Application of Level 2 Probabilistic Safety Assessment for Nuclear Power Plants. Specific Safety Guide

International Nuclear Information System (INIS)

2010-01-01

The objective of this Safety Guide is to provide recommendations for meeting the IAEA safety requirements in performing or managing a level 2 probabilistic safety assessment (PSA) project for a nuclear power plant; thus it complements the Safety Guide on level 1 PSA. One of the aims of this Safety Guide is to promote a standard framework, standard terms and a standard set of documents for level 2 PSAs to facilitate regulatory and external peer review of their results. It describes all elements of the level 2 PSA that need to be carried out if the starting point is a fully comprehensive level 1 PSA. Contents: 1. Introduction; 2. PSA project management and organization; 3. Identification of design aspects important to severe accidents and acquisition of information; 4. Interface with level 1 PSA: Grouping of sequences; 5. Accident progression and containment analysis; 6. Source terms for severe accidents; 7. Documentation of the analysis: Presentation and interpretation of results; 8. Use and applications of the PSA; Annex I: Example of a typical schedule for a level 2 PSA; Annex II: Computer codes for simulation of severe accidents; Annex III: Sample outline of documentation for a level 2 PSA study.

ASAMPSA-E guidance for level 2 PSA Volume 3. Verification and improvement of SAM strategies with L2 PSA

International Nuclear Information System (INIS)

Rahni, N.; Raimond, E.; Jan, P.; Lopez, J.; Loeffler, H.; Mildenberger, O.; Kubicek, J.; Vitazkova, J.; Ivanov, I.; Groudev, P.; Lajtha, G.; Serrano, C.; Zhabin, O.; Prosek, Andrej; Dirksen, G.; Yu, S.; Oury, L.; Hultqvist, G.

2016-01-01

For each NPP, severe accident management (SAM) strategies shall make use of components or systems and human resources to limit as far as possible the consequences of any severe accident on-site and off-site. L2 PSA is one of the tools that can be used to verify and improve these strategies. The present report (deliverable D40.5 of the project ASAMPSA-E) provides an opportunity for a comparison of objectives in the different countries in terms of SAM strategies verification and improvement. The report summarizes also experience of each partner (including potential deficiencies) involved in this activity, in order to derive some good practices and required progress, addressing: - SAM modeling in L2 PSA, - Positive and negative aspects in current SAM practices, - Discussion on possible criteria related to L2 PSA for verification and improvement: risk reduction (in relation with WP30 activities on risk metrics), reduction of uncertainties on the severe accident progression paths until NPP stabilization, reduction of human failure conditional probabilities (depending on the SAM strategy, the environmental conditions...), - Review with a perspective of verification and improvement of the main SAM strategies (corium cooling, RCS depressurization, control of flammable gases, reactivity control, containment function, containment pressure control, limitation of radioactive releases,...), - SAM strategies to be considered in the context of an extended L2 PSA (as far possible, depending on existing experience), taking into account all operating modes, accidents also occurring in the SFPs and long term and multi-unit accidents. The deliverable D40.5 is developed from the partners' experience. Many of the topics described here are beyond the common practices of L2 PSA applications: in some countries, L2 PSA application is limited to the calculations of frequencies of release categories with no formal requirement for SAM verification and improvement. (authors)

[Clinical evaluation of TANDEM PSA in Japanese cases and comparison with other methods].

Science.gov (United States)

Kuriyama, M; Yamamoto, N; Shinoda, I; Kawada, Y; Akimoto, S; Shimazaki, J

1995-01-01

Clinical evaluation of TANDEM PSA which is the most frequently used prostate specific antigen (PSA) assay method in the world and a comparison with other methods were performed in Japanese cases in a cooperative research fashion. The minimum detectable level of the method was found to be 0.50 ng of PSA in one ml of serum and 1.9 ng/ml was regarded as the upper normal value in Japanese males. The distribution of serum PSA showed a significant difference between the benign prostate hypertrophy (BPH) cases and patients with stage C or D prostate cancer. The sero-diagnosis prostate cancer at an early stage with the TANDEM PSA was difficult. The correlation to other methods of PSA detection was very high. Furthermore, the clinical use of the method in following-up the clinical course of prostate cancer patients was very useful. These findings suggested that the PSA detection using TANDEM PSA is applicable even in Japanese cases although the upper cut-off level is decreased.

PSA - a tool for the nuclear safety

International Nuclear Information System (INIS)

Himanen, R.

1992-01-01

The PSA-model for BWR-type reactors of Finnish power company, Teollisuuden Voima Oy (TVO) was finished in year 1989. This basic PSA model included all safety systems, normal operating systems and auxiliary systems. Today TVO is working to enlarge the PSA to level 2 (environmental effects, for the fires, for the floodings and the outages). The TVO's experiences has been showed the PSA an useful tool for the developing the safety of BWR's (orig.)

Use of PSA for improving the safety of French PWRs

International Nuclear Information System (INIS)

Lanore, J.M.; Chambon, J.L.

1994-06-01

Two French PWR Probabilistic Safety Assessment (PSA) studies were conducted for the standardized PWR series of 900 and 1300 MWe. Both PSA 900 and PSA 1300 are level 1 PSAs, that means their objective is the evaluation of core meltdown frequency. These studies have some specific features, in particular the treatment of shutdown conditions, the treatment of long term post-accidental situations, and a wide use of French experience feedback. The PSAs are used for safety improvements of the French PWRs. Following the PSA results, several modifications to plants concerning the dominant sequences were decided. (R.P.). 2 refs., 4 figs

Validation of Association of Genetic Variants at 10q with PSA Levels in Men at High Risk for Prostate Cancer

Science.gov (United States)

Chang, Bao-Li; Hughes, Lucinda; Chen, David Y. T.; Gross, Laura; Ruth, Karen; Giri, Veda N.

2013-01-01

Objectives Men with a family history of prostate cancer and African American men are at increased risk for prostate cancer and stand to benefit from individualized interpretation of PSA to guide screening strategies. The purpose of this study was to validate six previously identified markers among high-risk men enrolled in the Prostate Cancer Risk Assessment Program - a prostate cancer screening study. Patients and Methods Eligibility for PRAP includes men ages 35–69 years with a family history of prostate cancer, any African American male regardless of family history, and men with known BRCA gene mutations. GWAS markers assessed included rs2736098 (5p15.33), rs10993994 (10q11), rs10788160 (10q26), rs11067228 (12q24), rs4430796 (17q12), and rs17632542 (19q13.33). Genotyping methods included either Taqman® SNP Genotyping Assay (Applied Biosystems) or pyrosequencing. Linear regression models were used to evaluate the association between individual markers and log-transformed baseline PSA levels, while adjusting for potential confounders. Results 707 participants (37% Caucasian, 63% African American) with clinical and genotype data were included in the analysis. Rs10788160 (10q26) strongly associated with PSA levels among high-risk Caucasian participants (p<0.01), with a 33.2% increase in PSA level with each A-allele carried. Furthermore, rs10993994 (10q11) demonstrated an association to PSA level (p=0.03) in high-risk Caucasian men, with a 15% increase in PSA with each T-allele carried. A PSA adjustment model based on allele carrier status at rs10788160 and rs10993994 is proposed specific to high-risk Caucasian men. Conclusion Genetic variation at 10q may be particularly important in personalizing interpretation of PSA for high-risk Caucasian men. Such information may have clinical relevance in shared decision-making and individualized prostate cancer screening strategies for high-risk Caucasian men. Further study is warranted. PMID:23937305

Prioritization of design changes based on PSA

International Nuclear Information System (INIS)

Krajnc, B.; Mavko, B.

1996-01-01

Effective use of Probabilistic Safety Analyses (PSA) in the day to day plant operation is subject of intensive discussions among plant operators and regulators. There are several possible applications in which the PSA can be used, among those also to use the PSA approach for the quantification of influence of different proposed design changes to nuclear safety - influence on public safety - health. NPP Krsko is one of those plants that successfully completed its PSA project, with Level 1 and Level 2 analyses and effective know-how transfer. It also faces a number of regulatory and internally generated requirements for different design changes, mainly due to the fact that the plant is committed to continuous augmentation of nuclear safety. It is considered that the available tools and knowledge should be used and therefore applicable methodology should be developed for effective prioritization of proposed design changes by performing cost-benefit analyses for all major modifications - focusing on their influence on nuclear safety. Based on the above a new method for prioritization of design changes is proposed. The method uses Level 1 results (in the sense of plant damage states and their frequencies) directly as an input for further processing - first decision step to decide whether the proposed modification has or has no influence on nuclear safety. In Level 2 analyses the combination of probabilistic and deterministic approach was adopted. In fact the results of the deterministic analyses of severe accidents are treated in probabilistic manner due to large uncertainty of results. Finally to be able to perform plant specific cost benefit analyses so called partial Level 3 was defined. The proposed methods was preliminary tested and it gave favorable results. (author)

Combination of signal intensity measurements of lesions in the peripheral zone of prostate with MRI and serum PSA level for differentiating benign disease from prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Engelhard, K.; Kreckel, M. [Department of Radiology, Martha-Maria Hospital Nuernberg (Germany); Hollenbach, H.P.; Deimling, M. [Siemens Medical Engineering Group, Erlangen (Germany); Riedl, C. [Dept. of Urology, University of Erlangen-Nuernberg, Erlangen (Germany)

2000-12-01

The aim of this study was to predict the benign or malignant nature of a prostatic lesion by defining a threshold value of signal intensity ratio and a limiting value of serum prostate-specific antigen (PSA) in patients with elevated PSA level. Twenty-six patients with elevated PSA level and no hypoechogenic lesions at endosonography underwent MR imaging using an endorectal body phased-array coil at 1.5 T (Siemens Magnetom Symphony). A T2-weighted turbo-spin-echo (TSE) pulse sequence was applied in a transverse orientation. Two radiologists evaluated the images. In the presence of a pathological finding they defined regions of interest (ROI) in the suspicious pathological area of the peripheral zone and in muscle for reference. The quotient of the two ROIs was calculated and then correlated with the actual PSA level. Diagnosis was confirmed by prostate biopsy. Ten of 12 patients with quotients smaller than 4 showed cancer at histology. Nine of 12 men with cancer proven by biopsy had PSA levels higher than 10 ng/ml. A significant difference (p < 0.001) was found between the quotients of cancer and quotients of chronic prostatitis, fibrosis, or glandular atrophy. The accuracy of tumor differentiation of the method was 77 %. Measurement of signal intensity quotients in the peripheral zone of the prostate in combination with knowledge of defined limits of PSA levels the technique could be helpful in detecting additional cancer areas for prostate biopsy. False-negative tumor results of standard sextant biopsy can be reduced. In men with high PSA values the method has a role in differentiating between patients who require prostate biopsy and those of clinical observation. (orig.)

Serum complexed and free prostate-specific antigen (PSA) for the diagnosis of the polycystic ovarian syndrome (PCOS).

Science.gov (United States)

Diamandis, Eleftherios P; Stanczyk, Frank Z; Wheeler, Sarah; Mathew, Anu; Stengelin, Martin; Nikolenko, Galina; Glezer, Eli N; Brown, Marshall D; Zheng, Yingye; Chen, Yen-Hao; Wu, Hsiao-Li; Azziz, Ricardo

2017-10-26

Polycystic ovarian syndrome (PCOS) is a common cause of reproductive and metabolic dysfunction. We hypothesized that serum prostate-specific antigen (PSA) may constitute a new biomarker for hyperandrogenism in PCOS. We conducted a cross-sectional study of 45 women with PCOS and 40 controls. Serum from these women was analyzed for androgenic steroids and for complexed PSA (cPSA) and free PSA (fPSA) with a novel fifth- generation assay with a sensitivity of ~10 fg/mL for cPSA and 140 fg/mL for fPSA. cPSA and fPSA levels were about three times higher in PCOS compared to controls. However, in PCOS, cPSA and fPSA did not differ according to waist-to-hip ratio, Ferriman-Gallwey score, or degree of hyperandrogenemia or oligo-ovulation. In PCOS and control women, serum cPSA and fPSA levels were highly correlated with each other, and with free and total testosterone levels, but not with other hormones. Adjusting for age, body mass index (BMI) and race, cPSA was significantly associated with PCOS, with an odds ratio (OR) of 5.67 (95% confidence interval [CI]: 1.86, 22.0). The OR of PCOS for fPSA was 7.04 (95% CI: 1.65, 40.4). A multivariate model that included age, BMI, race and cPSA yielded an area-under-the-receiver-operating-characteristic curve of 0.89. Serum cPSA and fPSA are novel biomarkers for hyperandrogenism in PCOS and may have value for disease diagnosis.

Analysis of urinary PSA glycosylation is not indicative of high-risk prostate cancer.

Science.gov (United States)

Barrabés, Sílvia; Llop, Esther; Ferrer-Batallé, Montserrat; Ramírez, Manel; Aleixandre, Rosa N; Perry, Antoinette S; de Llorens, Rafael; Peracaula, Rosa

2017-07-01

The levels of core fucosylation and α2,3-linked sialic acid in serum Prostate Specific Antigen (PSA), using the lectins Pholiota squarrosa lectin (PhoSL) and Sambucus nigra agglutinin (SNA), can discriminate between Benign Prostatic Hyperplasia (BPH) and indolent prostate cancer (PCa) from aggressive PCa. In the present work we evaluated whether these glycosylation determinants could also be altered in urinary PSA obtained after digital rectal examination (DRE) and could also be useful for diagnosis determinations. For this purpose, α2,6-sialic acid and α1,6-fucose levels of urinary PSA from 53 patients, 18 biopsy-negative and 35 PCa patients of different aggressiveness degree, were analyzed by sandwich ELLA (Enzyme Linked Lectin Assay) using PhoSL and SNA. Changes in the levels of specific glycosylation determinants, that in serum PSA samples were indicative of PCa aggressiveness, were not found in PSA from DRE urine samples. Although urine is a simpler matrix for analyzing PSA glycosylation compared to serum, an immunopurification step was necessary to specifically detect the glycans on the PSA molecule. Those specific glycosylation determinants on urinary PSA were however not useful to improve PCa diagnosis. This could be probably due to the low proportion of PSA from the tumor in urine samples, which precludes the identification of aberrantly glycosylated PSA. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of PSA audit guideline and regulatory PSA model for SMART

International Nuclear Information System (INIS)

Cho, Namchul; Lee, Chang-Ju; Kim, I.S.

2012-01-01

SMART is under development for dual purposes of power generation and seawater desalination in Korea. It is an integral reactor type with a thermal power output of 330 MW and employs advanced design features such as a passive system for the removal of residual heat and also the setting of all the components of the primary system inside the reactor pressure vessel. It is essential to develop new probabilistic safety assessment (PSA) validation guidance for SMART. For the purpose of regulatory verification to the risk level of SMART, the insights and key issues on the PSA are identified with referring some worldwide safety guides as well as its design characteristics. Regulatory PSA model under the development for the design confirmation and its preliminary result are also described. (authors)

Early detection of prostate cancer in Syria using T.PSA and F.PSA

International Nuclear Information System (INIS)

Adel, M.; Abu Daher, D.

2009-12-01

The aim of the current study is performing an initial prostate cancer screening test using PSA and F PSA tumour markers. A total of 3000 men in 40-75 years of age were participated in this study. Demographic and clinical data for subjects were collected by the programme staff. Total PSA and free PSA assays were determined using the ImunoTech total and free PSA assay kits, based on IRMA technique (kindly provided by the International Atomic Energy Agency). Criteria for participating in this study included : 1) men of age 50-75 (men of age as low as 40 were included in case of positive family history). 2) No previous history of prostate cancer. The following parameters were followed to refer the suspicious cases to a specialized hospital specific tests: 1)PSA>3 ng/ml . 2)High PSA value according to the participant age group. 3) Low F/TPSA ratio. In the hospital the following tests were performed:1) Complete clinical exam including DRE.2)TRUS in some cases.3) Biopsy for highly suspicious cases. 4)The low suspicious cases were retested in six months. Out of 338 cases referred to a specialized hospital, 264 cases were shown prostatic benign prostatic hyperplasia (BPH),while 36 cases proved to be prostatic cancer. However, the contact was lost in 36 cases because of changing the phone number or travelling outside the country . The detection rate of prostate cancer among all participating cases in this study was 1.2%, while this ratio was 10.7% among the referred cases. F/TPSA ratio has shown a good ability to discriminate between prostate cancer and benign prostatic hyperplasia. (author)

Comparison and lessons learned from plant specific PSA of German NPP

International Nuclear Information System (INIS)

Balfanz, Hans-Peter; Berg, H.P.

2000-01-01

PSA are launched in frame of Periodic Safety Reviews (PSR) in Germany. The aims are to identify overall safety level and relative weak points. Some backfitting measures have been realized for older plants to remove relative weak points and to bring these plants to the state of the art. In this field PSA is well accepted today and is seen as a valuable tool supplementing the deterministic analysis. Main application of PSA within PSR is planned to become mandatory as part of the revision of the German Atomic Energy Act. According to the German PSA Guideline plant specific PSA level 1+ were performed for all 19 In comparison with international practice German PSA are very detailed. Otherwise they do not handle all external events, non-power states and accident management measures as discussed before. The New PSA guideline will cover these aspects and therefore analysts have to take them into account in further PSA. Moreover gathering of plant specific data is needed. The development in this field is driven by the utilities (for instance in frame of their so-called ZEDB project). Public discussion about quantitative risk of industrial hazards is quite limited in Germany and PSA results have only few impacts to this respect. Independent from this PSA for NPP is understood as a diverse tool in supporting the deterministic licensing and supervision process. Risk based decision making as well as informed regulation are just only of the beginning. State of PSA of NPP in Germany, comparison of PSA result of different NPP, German PSA guideline and state of discussion of further development and recommendation of further development of PSA of NPP are discussed in this paper in more detail. (S.Y.)

Comparison and lessons learned from plant specific PSA of German NPP

Energy Technology Data Exchange (ETDEWEB)

Balfanz, Hans-Peter [TUEV Nord, Hamburg (Germany); Berg, H.P.

2000-07-01

PSA are launched in frame of Periodic Safety Reviews (PSR) in Germany. The aims are to identify overall safety level and relative weak points. Some backfitting measures have been realized for older plants to remove relative weak points and to bring these plants to the state of the art. In this field PSA is well accepted today and is seen as a valuable tool supplementing the deterministic analysis. Main application of PSA within PSR is planned to become mandatory as part of the revision of the German Atomic Energy Act. According to the German PSA Guideline plant specific PSA level 1+ were performed for all 19 In comparison with international practice German PSA are very detailed. Otherwise they do not handle all external events, non-power states and accident management measures as discussed before. The New PSA guideline will cover these aspects and therefore analysts have to take them into account in further PSA. Moreover gathering of plant specific data is needed. The development in this field is driven by the utilities (for instance in frame of their so-called ZEDB project). Public discussion about quantitative risk of industrial hazards is quite limited in Germany and PSA results have only few impacts to this respect. Independent from this PSA for NPP is understood as a diverse tool in supporting the deterministic licensing and supervision process. Risk based decision making as well as informed regulation are just only of the beginning. State of PSA of NPP in Germany, comparison of PSA result of different NPP, German PSA guideline and state of discussion of further development and recommendation of further development of PSA of NPP are discussed in this paper in more detail. (S.Y.)

Short overview of PSA quantification methods, pitfalls on the road from approximate to exact results

International Nuclear Information System (INIS)

Banov, Reni; Simic, Zdenko; Sterc, Davor

2014-01-01

Over time the Probabilistic Safety Assessment (PSA) models have become an invaluable companion in the identification and understanding of key nuclear power plant (NPP) vulnerabilities. PSA is an effective tool for this purpose as it assists plant management to target resources where the largest benefit for plant safety can be obtained. PSA has quickly become an established technique to numerically quantify risk measures in nuclear power plants. As complexity of PSA models increases, the computational approaches become more or less feasible. The various computational approaches can be basically classified in two major groups: approximate and exact (BDD based) methods. In recent time modern commercially available PSA tools started to provide both methods for PSA model quantification. Besides availability of both methods in proven PSA tools the usage must still be taken carefully since there are many pitfalls which can drive to wrong conclusions and prevent efficient usage of PSA tool. For example, typical pitfalls involve the usage of higher precision approximation methods and getting a less precise result, or mixing minimal cuts and prime implicants in the exact computation method. The exact methods are sensitive to selected computational paths in which case a simple human assisted rearrangement may help and even switch from computationally non-feasible to feasible methods. Further improvements to exact method are possible and desirable which opens space for a new research. In this paper we will show how these pitfalls may be detected and how carefully actions must be done especially when working with large PSA models. (authors)

Clinical performance of serum [-2]proPSA derivatives, %p2PSA and PHI, in the detection and management of prostate cancer.

Science.gov (United States)

Huang, Ya-Qiang; Sun, Tong; Zhong, Wei-De; Wu, Chin-Lee

2014-01-01

Prostate-specific antigen (PSA) has been widely used as a serum marker for prostate cancer (PCa) screening or progression monitoring, which dramatically increased rate of early detection while significantly reduced PCa-specific mortality. However, a number of limitations of PSA have been noticed. Low specificity of PSA may lead to overtreatment in men who presenting with a total PSA (tPSA) level of PHI) and %p2PSA, which were defined as [(p2PSA/fPSA) × √ tPSA] and [(p2PSA/fPSA) × 100] respectively, have been suggested to be increased in PCa and can better distinguish PCa from benign prostatic diseases than tPSA or fPSA. We performed a systematic review of the available scientific evidences to evaluate the potentials of %p2PSA and PHI in clinical application. Mounting evidences suggested that both %p2PSA and PHI possess higher area under the ROC curve (AUC) and better specificity at a high sensitivity for PCa detection when compare with tPSA and %fPSA. It indicated that measurements of %p2PSA and PHI significantly improved the accuracy of PCa detection and diminished unnecessary biopsies. Furthermore, elevations of %p2PSA and PHI are related to more aggressive diseases. %p2PSA and PHI might be helpful in reducing overtreatment on indolent cases or assessing the progression of PCa in men who undergo active surveillance. Further studies are needed before being applied in routine clinical practice.

Experience from the comparison of two PSA-studies

International Nuclear Information System (INIS)

Holmberg, J.; Pulkkinen, U.

2001-03-01

Two probabilistic safety assessments (PSA) made for nearly identical reactors units (Forsmark 3 and Oskarshamn 3) have been compared. Two different analysis teams made the PSAs, and the analyses became quite different. The goal of the study is to identify, clarify and explain differences between PSA-studies. The purpose is to understand limitations and uncertainties in PSA, to explain reasons for differences between PSA-studies, and to give recommendations for comparison of PSA-studies and for improving the PSA-methodology. The reviews have been made by reading PSA-documentation, using the computer model and interviewing persons involved in the projects. The method and findings have been discussed within the project group. Both the PSA-project and various parts in the PSA-model have been reviewed. A major finding was that the two projects had different purpose and thus had different resources, scope and even methods in their study. The study shows that comparison of PSA results from different plants is normally not meaningful. It takes a very deep knowledge of the PSA studies to make a comparison of the results and usually one has to ensure that the compared studies have the same scope and are based on the same analysis methods. Harmonisation of the PSA-methodology is recommended in the presentation of results, presentation of methods, scope main limitation and assumption, and definitions for end states, initiating events and common cause failures. This would facilitate the comparison of the studies. Methods for validation of PSA for different application areas should be developed. The developed PSA review standards can be applied for a general validation of a study. The most important way to evaluate the real feasibility of PSA can take place only with practical applications. The PSA-documentation and models can be developed to facilitate the communication between PSA-experts and users. In any application consultation with the PSA-expert is however needed. Many

PSA in America

International Nuclear Information System (INIS)

Linn, M.A.; Cunningham, M.A.; Johnson, D.H.

1996-01-01

Although the concept of acceptable risk has always been the foundation of the nuclear industry design, the use of formal PSA (or PRA-probabilistic risk assessment) in the U.S. nuclear power industry has followed an unusual path in arriving at its current level of notability. Prior to 1975, probabilistic evaluations were limited to a few specific applications such as the evaluation of man-made (i.e., airplane crashes) and natural (i.e., earthquakes) hazards. In 1975, the industry was introduced to comprehensive PSA by the Reactor Safety Study (WASH-1400). However, the study languished in relative obscurity until the accident at Three Mile Island 2 (TMI-2) in 1979. This event significantly altered the industry's view of severe accidents in the U.S. and worldwide. Investigative committees of TMI-2 recommended that PSA techniques be more widely used to augment the traditional deterministic methods of determining nuclear plant safety. This initiated an unprecedented effort by nuclear regulators and licensees worldwide to significantly improve the state of knowledge of severe accidents at nuclear power plants. In the U.S., use of PSA began to increase as evidenced by its application in the anticipated transient without scram and station blackout rulemakings, generic issue prioritization and resolution, risk-based inspection guidelines, backfit policy, and technical specification improvements. However, broad application of probabilistic techniques to the industry as a whole was initiated in 1986 with the publication of Safety Goals for the Operation of Nuclear Power Plant; Policy Statement. This put PSA front and center in the U.S. regulatory arena by open-quotes establish[ing] goals that broadly define an acceptable level of radiological risk that might be imposed on the public as a result of nuclear power plant operation.close quotes Both qualitative safety goals and quantitative objectives were articulated in this policy statement

Methodology for fire PSA during design process

International Nuclear Information System (INIS)

Kollasko, Heiko; Blombach, Joerg

2009-01-01

Fire PSA is an essential part of a full scope level 1 PSA. Cable fires play an important role in fire PSA. Usually, cable routing is therefore modeled in detail. During the design of new nuclear power plants the information on cable routing is not yet available. However, for the use of probabilistic safety insights during the design and for licensing purposes a fire PSA may be requested. Therefore a methodology has been developed which makes use of the strictly divisional separation of redundancies in the design of modern nuclear power plants: cable routing is not needed within one division but replaced by the conservative assumption that all equipment fails due to a fire in the concerned division; critical fire areas are defined where components belonging to different divisions may be affected by a fire. For the determination of fire frequencies a component based approach is proposed. The resulting core damage frequencies due to fire are conservative. (orig.)

Probability of an Abnormal Screening PSA Result Based on Age, Race, and PSA Threshold

Science.gov (United States)

Espaldon, Roxanne; Kirby, Katharine A.; Fung, Kathy Z.; Hoffman, Richard M.; Powell, Adam A.; Freedland, Stephen J.; Walter, Louise C.

2014-01-01

Objective To determine the distribution of screening PSA values in older men and how different PSA thresholds affect the proportion of white, black, and Latino men who would have an abnormal screening result across advancing age groups. Methods We used linked national VA and Medicare data to determine the value of the first screening PSA test (ng/mL) of 327,284 men age 65+ who underwent PSA screening in the VA healthcare system in 2003. We calculated the proportion of men with an abnormal PSA result based on age, race, and common PSA thresholds. Results Among men age 65+, 8.4% had a PSA >4.0ng/mL. The percentage of men with a PSA >4.0ng/mL increased with age and was highest in black men (13.8%) versus white (8.0%) or Latino men (10.0%) (PPSA >4.0ng/mL ranged from 5.1% of Latino men age 65–69 to 27.4% of black men age 85+. Raising the PSA threshold from >4.0ng/mL to >10.0ng/mL, reclassified the greatest percentage of black men age 85+ (18.3% absolute change) and the lowest percentage of Latino men age 65–69 (4.8% absolute change) as being under the biopsy threshold (PPSA threshold together affect the pre-test probability of an abnormal screening PSA result. Based on screening PSA distributions, stopping screening among men whose PSA 10ng/ml has the greatest effect on reducing the number of older black men who will face biopsy decisions after screening. PMID:24439009

The optimal timing to perform 18F/11C-choline PET/CT in patients with suspicion of relapse of prostate cancer: trigger PSA versus PSA velocity and PSA doubling time.

Science.gov (United States)

Calabria, Ferdinando; Rubello, Domenico; Schillaci, Orazio

2014-12-09

In the present short communication we considered the main publications focused on trigger prostate-specific antigen (PSA) and PSA kinetics that systematically compared 18F to 11C-choline PET/CT in order to establish the optimal time to perform choline PET/CT in relation to the trigger values and velocity, as well as doubling time of PSA serum levels.

A level III PSA for the inherently safe CAREM-25 nuclear power station

International Nuclear Information System (INIS)

Baron, Jorge H.; Nunez McLeod, J.; Rivera, S.S.

2000-01-01

A Level III PSA has been performed for the inherently safe CAREM-25 nuclear power station, as a requirement for licensing according to argentinian regulations. The CAREM-25 project is still at a detailed design state, therefore only internal events have been considered, and a representative site has been assumed for dose estimations. Several conservative hypothesis have been formulated, but even so an overall core melt frequency of 2.3E -5 per reactor year has been obtained. The risk estimations comply with the regulations. The risk values obtained are compared to the 700MW(e) nuclear power plant Atucha II PSA result, showing an effective risk reduction not only in the severe accident probability but alto in the consequence component of the risk estimation. (author)

Summary report for the second TUV-workshop proceedings on living PSA application

International Nuclear Information System (INIS)

1991-01-01

This workshop on living PSA Application was organized to support the OECD/NEA CSNI-Principal Working Group No.5 on Risk Assessment for an international exchange of experience on living PSA application. The first session was devoted to Living PSA Applications and the second session to Tools for Living PSA. Living PSA Applications: Reasons for performing PSA (regulatory requirement, targets; corporate requirement, targets; safety related activity prioritization; other); Logistic of Living PSA Management (Corporate management involvement, Decision making levels and guidance, Plant level involvement, Required personnel commitment, Frequency and extent of re-quantification of PSA, Types of safety/risk parameters to be monitored, Quality assurance on maintaining Living PSA); Examples of Application (Experiences of application, State of Living PSA/e.g. all accident sequences involved, Details of component level involvement). Tools for Living PSA: Data Collection Systems and Codes (Source and type of data collected, Probabilistic parameter quantification, Interface to basic event data, Data code systems). An executive summary of the workshop is given

Correlation of Serum Androgens and Pituitary Hormone Levels with Serum PSA Less Than 2.5 NG/ML

Directory of Open Access Journals (Sweden)

Mustafa Sofikerim

2007-01-01

Full Text Available The aim of this clinical study was to determine whether there is a relationship between total serum testosterone, free testosterone, FSH (Follicle-Stimulating Hormone, LH (Luteinizing Hormone and serum prostate specific antigen (PSA levels. We postulated that such a correlation existed then the use of hormone specific reference ranges might enhance the usefullness of PSA concentrations <2.5 ng/mL as a marker for prostate cancer.

Prediction of PSA bounce after permanent prostate brachytherapy for localized prostate cancer

International Nuclear Information System (INIS)

Kanai, Kunimitsu; Nakashima, Jun; Sugawara, Akitomo

2009-01-01

We aimed to calculate the frequency and features of the development of a prostate-specific antigen (PSA) bounce after prostate brachytherapy alone, to correlate the bounce with clinical and dosimetric factors and to identify factors that predict PSA bounce. PSA bounce was evaluated in 86 patients with T1-T2 prostate cancer who underwent radioactive seed implantation using iodine-125 (I-125) without hormonal therapy or external-beam radiation therapy (EBRT) from September 2004 to December 2007. A PSA bounce was defined as a rise of at least 0.4 ng/ml greater than a previous PSA level with a subsequent decline equal to, or less than, the initial nadir. Calculated by the Kaplan-Meier method, the incidence of PSA bounce at a 2-year follow-up was 26%. Median time to the PSA bounce was 15 months. Univariate analysis demonstrated that age, dose received by 90% of the prostate gland (D90), volume of gland receiving 100% of the prescribed dose (V100), and V150 were significantly associated with the PSA bounce, while pretreatment PSA level, Gleason score, pretreatment prostate volume, clinical T stage, and V200 were not. In multivariate analysis, age 67 years or less and D90 more than 180 Gy were identified as independent factors for predicting the PSA bounce (P<0.05). PSA bounce is not a rare phenomenon after prostate brachytherapy. It is more common in younger patients and patients receiving higher doses of radiation. (author)

Men presenting with prostate-specific antigen (PSA) values of over 100 ng/mL.

Science.gov (United States)

Ang, Mann; Rajcic, Branimir; Foreman, Darren; Moretti, Kim; O'Callaghan, Michael E

2016-04-01

To investigate overall survival and prostate cancer-specific mortality in men with prostate cancer presenting with a PSA level PSA level extracted from the South Australian Prostate Cancer Clinical Outcomes Collaborative (SA-PCCOC) database. Men included were diagnosed between January 1998 and August 2013. Patients were divided into groups according to diagnostic PSA level: 500 ng/mL. Outcomes measured include overall survival and prostate cancer-specific mortality. Clinical stage, Gleason score and the presence of bony metastasis was evaluated to determine if they were prognostic factors in patients with PSA over 100 at diagnosis. Cox proportional hazards and competing risks regression were used to model overall survival and prostate cancer-specific mortality outcomes respectively. Of this cohort, 241 patients (4.2%) had a diagnostic PSA level >100 ng/mL. Patients with PSA >100 ng/mL have a significant reduction in five (29.1% vs 62.5% vs 87%) and ten-year (18.2% vs 36.7% vs 70.7%) overall survival when compared to men with diagnostic PSA 20-100 and PSA level at diagnosis. Overall survival was associated with PSA level, Gleason score and age. There was a linear increase in risk (overall survival) as PSA increased until 200 and no association thereafter. Models of overall survival and prostate cancer-specific mortality incorporating a risk stratification developed by Izumi et al. predicted overall survival but not prostate cancer-specific mortality. The use of this stratification did not improve model accuracy. Only a small number of men (4.2%) with prostate cancer present with PSA >100 ng/mL at diagnosis. Overall survival at five and ten years was significantly poorer in patients with PSA >100 ng/mL. In this cohort of men presenting with PSA >100 at diagnosis, PSA level was not associated with prostate cancer-specific mortality. Gleason score and metastases are significant prognostic factors in this group of men. © 2016 The Authors BJU International © 2016

Level 1 shutdown and low power operation of Mochovce NPP, Unit 1, Slovakia

International Nuclear Information System (INIS)

Halada, P.; Cillik, I.; Stojka, T.; Kuzma, M.; Prochaska, J.; Vrtik, L.

2004-01-01

The paper presents general approach, used methods and form of documentation of the results that have been applied within the shutdown and low power PSA (SPSA) study for Mochovce NPP, Unit 1, Slovakia. The SPSA project was realized by VUJE Trnava Inc., Slovakia in 2001-2002 years. The Level 1 SPSA study for Mochovce NPP Unit 1 covers internal events as well as internal (fires, floods and heavy load drop) and external (aircraft crash, extreme meteorological conditions, seismic event and influence of surrounding industry) hazards. Mochovce NPP consists of two operating units equipped with VVER 440/V213 reactors safety upgraded before construction finishing and operation start. 87 safety measures based on VVER 440 operational experience and international mission insights were implemented to enhance its operational and nuclear safety. The SPSA relates to full power PSA (FPSA) as a continuation of the effort to create a harmonized level 1 PSA model for all operational modes of the plant with the goal to use it for further purposes as follows: Real Time Risk Monitor, Maintenance Optimization, Technical Specifications Optimization, Living PSA. (author)

What do PSA changes after radiotherapy with or without prior androgen deprivation mean?

International Nuclear Information System (INIS)

Denham, J.W.; Woodhead, D.; Lamb, D.S.; Duchesne, G.

2003-01-01

The TROG 96.01 randomised patients with Stage B2 and C prostate cancer to radiotherapy alone to 66 Gy (RT), 3 months maximal androgen deprivation (MAD) with goserelin and flutamide prior to and during RT, and 6 months MAD prior to and during RT. Minimum follow up time is now 3 years. Prior to preliminary analysis of one of the trial's main endpoints biochemical relapse free survival (bRFS), the prostate-specific antigen (PSA) time course for every patient was evaluated to assess the performance of the ASTRO definition of biochemical failure (BF). Following MAD and RT PSA levels immediately rise in the majority of cases (PSA 'rebound'). In over 50% of cases, PSA levels then plateau at <1 ng/ml for 2 - 3 years prior to clear evidence of failure. Premature diagnosis of BF is possible in some of these cases. Fluctuations in PSA level ('bouncing') are more frequent after MAD and RT. As a result there can be difficulty in interpreting the ASTRO definition of BF in cases where overall PSA trend is upwards shortly after completion of therapy. In patients experiencing BF, the rate of PSA rise often corresponds to the site of failure. PSA doubling times (DT) under 7 months are usually associated with development of bony metastases, while DTs greater than that are usually associated with local failure. Decline in PSA levels following RT alone is frequently not mono-exponential and patients with those patterns experience lower PSA nadir levels and are subject to lower risks of all forms of relapse. These patients also survive longer. In cases where PSA descent patterns are discernable after MAD and RT, opposite trends are seen. Caution is necessary in diagnosing BF after MAD plus RT. Variations in the natural history of prostate cancer are reflected by variations in the rate of PSA changes following therapy. The importance of monitoring this marker and evaluating its time course is emphasised. Prospective studies are needed

Survey of Dynamic PSA Methodologies

International Nuclear Information System (INIS)

Lee, Hansul; Kim, Hyeonmin; Heo, Gyunyoung; Kim, Taewan

2015-01-01

Event Tree(ET)/Fault Tree(FT) are significant methodology in Probabilistic Safety Assessment(PSA) for Nuclear Power Plants(NPPs). ET/FT methodology has the advantage for users to be able to easily learn and model. It enables better communication between engineers engaged in the same field. However, conventional methodologies are difficult to cope with the dynamic behavior (e.g. operation mode changes or sequence-dependent failure) and integrated situation of mechanical failure and human errors. Meanwhile, new possibilities are coming for the improved PSA by virtue of the dramatic development on digital hardware, software, information technology, and data analysis.. More specifically, the computing environment has been greatly improved with being compared to the past, so we are able to conduct risk analysis with the large amount of data actually available. One method which can take the technological advantages aforementioned should be the dynamic PSA such that conventional ET/FT can have time- and condition-dependent behaviors in accident scenarios. In this paper, we investigated the various enabling techniques for the dynamic PSA. Even though its history and academic achievement was great, it seems less interesting from industrial and regulatory viewpoint. Authors expect this can contribute to better understanding of dynamic PSA in terms of algorithm, practice, and applicability. In paper, the overview for the dynamic PSA was conducted. Most of methodologies share similar concepts. Among them, DDET seems a backbone for most of methodologies since it can be applied to large problems. The common characteristics sharing the concept of DDET are as follows: • Both deterministic and stochastic approaches • Improves the identification of PSA success criteria • Helps to limit detrimental effects of sequence binning (normally adopted in PSA) • Helps to avoid defining non-optimal success criteria that may distort the risk • Framework for comprehensively considering

Survey of Dynamic PSA Methodologies

Energy Technology Data Exchange (ETDEWEB)

Lee, Hansul; Kim, Hyeonmin; Heo, Gyunyoung [Kyung Hee University, Yongin (Korea, Republic of); Kim, Taewan [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2015-05-15

Event Tree(ET)/Fault Tree(FT) are significant methodology in Probabilistic Safety Assessment(PSA) for Nuclear Power Plants(NPPs). ET/FT methodology has the advantage for users to be able to easily learn and model. It enables better communication between engineers engaged in the same field. However, conventional methodologies are difficult to cope with the dynamic behavior (e.g. operation mode changes or sequence-dependent failure) and integrated situation of mechanical failure and human errors. Meanwhile, new possibilities are coming for the improved PSA by virtue of the dramatic development on digital hardware, software, information technology, and data analysis.. More specifically, the computing environment has been greatly improved with being compared to the past, so we are able to conduct risk analysis with the large amount of data actually available. One method which can take the technological advantages aforementioned should be the dynamic PSA such that conventional ET/FT can have time- and condition-dependent behaviors in accident scenarios. In this paper, we investigated the various enabling techniques for the dynamic PSA. Even though its history and academic achievement was great, it seems less interesting from industrial and regulatory viewpoint. Authors expect this can contribute to better understanding of dynamic PSA in terms of algorithm, practice, and applicability. In paper, the overview for the dynamic PSA was conducted. Most of methodologies share similar concepts. Among them, DDET seems a backbone for most of methodologies since it can be applied to large problems. The common characteristics sharing the concept of DDET are as follows: • Both deterministic and stochastic approaches • Improves the identification of PSA success criteria • Helps to limit detrimental effects of sequence binning (normally adopted in PSA) • Helps to avoid defining non-optimal success criteria that may distort the risk • Framework for comprehensively considering

Can Prostate Imaging Reporting and Data System Version 2 reduce unnecessary prostate biopsies in men with PSA levels of 4-10 ng/ml?

Science.gov (United States)

Xu, Ning; Wu, Yu-Peng; Chen, Dong-Ning; Ke, Zhi-Bin; Cai, Hai; Wei, Yong; Zheng, Qing-Shui; Huang, Jin-Bei; Li, Xiao-Dong; Xue, Xue-Yi

2018-05-01

To explore the value of Prostate Imaging Reporting and Data System Version 2 (PI-RADS v2) for predicting prostate biopsy results in patients with prostate specific antigen (PSA) levels of 4-10 ng/ml. We retrospectively reviewed multi-parameter magnetic resonance images from 528 patients with PSA levels of 4-10 ng/ml who underwent transrectal ultrasound-guided prostate biopsies between May 2015 and May 2017. Among them, 137 were diagnosed with prostate cancer (PCa), and we further subdivided them according to pathological results into the significant PCa (S-PCa) and insignificant significant PCa (Ins-PCa) groups (121 cases were defined by surgical pathological specimen and 16 by biopsy). Age, PSA, percent free PSA, PSA density (PSAD), prostate volume (PV), and PI-RADS score were collected. Logistic regression analysis was performed to determine predictors of pathological results. Receiver operating characteristic curves were constructed to analyze the diagnostic value of PI-RADS v2 in PCa. Multivariate analysis indicated that age, PV, percent free PSA, and PI-RADS score were independent predictors of biopsy findings, while only PI-RADS score was an independent predictor of S-PCa (P PSA, and PI-RADS score were 0.570, 0.430, 0.589 and 0.836, respectively. The area under the curve for diagnosing S-PCa with respect to PI-RADS score was 0.732. A PI-RADS score of 3 was the best cutoff for predicting PCa, and 4 was the best cutoff for predicting S-PCa. Thus, 92.8% of patients with PI-RADS scores of 1-2 would have avoided biopsy, but at the cost of missing 2.2% of the potential PCa cases. Similarly, 83.82% of patients with a PI-RADS score ≤ 3 would have avoided biopsy, but at the cost of missing 3.3% of the potential S-PCa cases. PI-RADS v2 could be used to reduce unnecessary prostate biopsies in patients with PSA levels of 4-10 ng/ml.

Serum PSA Evaluations during salvage radiotherapy for post-prostatectomy biochemical failures as prognosticators for treatment outcomes

International Nuclear Information System (INIS)

Do, Tri; Dave, Giatri; Parker, Robert; Kagan, A. Robert

2001-01-01

Introduction: Serum prostate specific antigen (PSA) levels have proved to be sensitive markers for the diagnosis of prostate cancer. In addition, PSA levels are useful for detecting and monitoring prostate cancer progression after radiotherapy. Serum PSA evaluations during radiotherapy, however, have not been well documented. In this study, we investigate the prognostic value of PSA evaluations during salvage radiotherapy for prostatectomy failures. Methods: Forty-one patients with biochemical failures after prostatectomy treated with salvage radiotherapy consented to have their serum PSA levels evaluated at 30 Gy and 45 Gy of irradiation. All 41 patients had negative metastatic workup and pathologically uninvolved pelvic lymph nodes at the time of referral for salvage radiotherapy. Radiation therapy was delivered with 10-25 MV photons, with doses of 59.4-66.6 Gy. No patients received hormonal ablation therapy before irradiation. Results: The mean follow-up for all patients was 30.9 months. At last follow-up, 28/41 patients (68.3%) were free from biochemical failure, with 20 of 41 patients (48.8%) expressing undetectable PSA levels. Serum PSA evaluations at 30 Gy did not significantly predict for either biochemical (p=0.0917) or clinical (p=0.106) disease-free outcome. However, serum PSA evaluations at 45 Gy significantly predicted for both biochemical (p=0.0043) and clinical (p=0.0244) disease-free outcomes, with PSA elevations at 45 Gy significantly associated with poor outcomes. On univariate analysis of prognosticators for biochemical failures, the following were significant: an elevation in serum PSA levels at 45 Gy, detectable serum PSA immediately after prostatectomy, Gleason score 7-10, and serum PSA level >1 ng/ml before salvage radiotherapy. Conclusion: Evaluation of serum PSA level at 45 Gy of salvage radiotherapy for biochemical relapses after prostatectomy may serve as a significant prognosticator for both biochemical and clinical disease-free outcomes

PSA Level 2 activities for RBMK reactors

International Nuclear Information System (INIS)

Gubler, R.

1998-01-01

Probabilistic safety analyses (PSAs) of the boiling water graphite moderated pressure tube reactors (RBMKs) have been developed only recently and they are limited to Level 1. Activities at the IAEA were first motivated because of the difficulties to characterize core damage for RBMK reactors. Core damage probability is used in documents of the IAEA as a convenient single valued measure, for example for probabilistic safety criteria. The limited number of PSAs that have been completed for the RBMK reactors have shown that several special features of these channel type reactors necessitate revisiting of the characterization of core damage for these reactors. Furthermore, it has become increasingly evident that detailed deterministic analysis of DBAs and beyond design basis accidents reveal considerable insights into RBMK response to various accident conditions. These analyses can also help in better characterizing the outstanding phenomenological uncertainties, improved EOPs and AM strategies, including potential risk-beneficial accident negative backfits. The deterministic efforts should be focused first on elucidating accident progression processes and phenomena, and second on finding, qualifying and implementing procedures to minimize the risk of severe accident states The IAEA PSA procedures were mainly developed in New of vessel type LWRs, and would therefore require extensions to make them directly applicable. to channel type reactors. (author) (author)

Guidance for Decision Making based on Extended PSA. Volume 1 - Summary report

International Nuclear Information System (INIS)

Loeffler, H.; Kumar, M.; Raimond, E.

2016-01-01

This report of ASAMPSA-E project is a summary report of the WP30 activities which were intended to develop guidance on decision-making process based on extended PSA results, when the PSA scope has been extended to all sources of radioactivity, all internal and relevant external events. It summarizes the ASAMPSA-E recommendations on: - the lessons of Fukushima Dai-ichi accident for PSA, - the risk metrics, - the method for identifying Initiating Events and Hazards for an Extended PSA (screening), - the link between extended PSA and the defense-in-depth concept. The report then provides some general considerations on application of extended PSA results, criteria that can be applied and also some difficulties inherent to the status of extended PSAs. (authors)

One Approach to the Fire PSA Uncertainty Analysis

International Nuclear Information System (INIS)

Simic, Z.; Mikulicic, V.; Vukovic, I.

2002-01-01

Experienced practical events and findings from the number of fire probabilistic safety assessment (PSA) studies show that fire has high relative importance for nuclear power plant safety. Fire PSA is a very challenging phenomenon and a number of issues are still in the area of research and development. This has a major impact on the conservatism of fire PSA findings. One way to reduce the level of conservatism is to conduct uncertainty analysis. At the top-level, uncertainty of the fire PSA can be separated in to three segments. The first segment is related to fire initiating events frequencies. The second uncertainty segment is connected to the uncertainty of fire damage. Finally, there is uncertainty related to the PSA model, which propagates this fire-initiated damage to the core damage or other analyzed risk. This paper discusses all three segments of uncertainty. Some recent experience with fire PSA study uncertainty analysis, usage of fire analysis code COMPBRN IIIe, and uncertainty evaluation importance to the final result is presented.(author)

Clinical impact of body mass index on prostate biopsy in patients with intermediate PSA levels

International Nuclear Information System (INIS)

Sekita, Nobuyuki; Chin, Kensei; Fujimura, Masaaki; Mikami, Kazuo; Suzuki, Hiroyoshi; Kamijima, Shuichi

2008-01-01

From April 2005 to September 2007, 480 patients underwent transrectal prostate biopsy at our institution. The clinical data including age, serum prostate specific antigen (PSA) level, prostate volume and body mass index (BMI) were obtained, and the cancer detection rates and pathological findings were evaluated in 305 cases with a PSA concentration of 4.0 to 10.0 ng/ml. Prostate volume was calculated from magnetic resonance imaging (MRI) findings. The 305 patients were categorized according to their BMI into three groups (normal, less than 22 kg/m 2 ; overweight, 22-25 kg/m 2 ; and obese, more than 25 kg/m 2 ). Cancer detection rates and histopathologic findings were compared between the groups. Multivariate logistic regression analysis was also performed. Prostate cancer was detected in 127 patients. No significant differences in BMI were observed between biopsy-positive and biopsy-negative cases (p=0.965), and the detection rates of prostate cancer observed in the three groups were not significantly different. There was a significant association between BMI and the findings of high Gleason score (more than 4+3) (p=0.048). BMI was not a contributory factor of prostate cancer detection for cases with intermediate PSA levels; however, patients with high BMI may have high-grade malignancy features. (author)

Insights of PSA studies made for operating nuclear power stations in Finland

International Nuclear Information System (INIS)

Laaksonen, J.; Virolainen, R.

1991-01-01

In 1984 the Finnish regulatory authority (STUK) required the utilities to make plant specific probabilistic safety assessment (PSA) studies for each plant. It was also strongly recommended that most of the work be made by plant personnel. This advice was well observed by both utilities. Results of level 1 PSA studies were submitted for regulatory review in June 1989. Only internal initiating events, including loss-of-offsite power and human errors, were considered at this stage. Each study took an effort of 12 to 20 man years. A thorough regulatory review, about two man years per plant, is currently underway, and will cause some changes in the initial results of the studies. The utilities are continuing their PSA work with the fire and flood analysis, and then with the analysis of risks during start-up and shutdown conditions. As soon as a level 1 PSA study has been reviewed, and a common understanding of the models and data has been reached between the utility and the STUK, this basic PSA version will be the first element of a living PSA. The second element is a user friendly PSA code that can rapidly run through the quantitative part of the study and thus easily indicate the influence of any deviation from the basic version. The third element is plant specific data collection and processing system. The living PSA for the first plant is expected to be fully operational sometime next year. The first use of the living PSA will be the safety assessment of proposed plant modifications and a systematic re-evaluation of technical specifications

Isolation and characterization of wild-type lipoxygenase LOX(Psa)1 from Pleurotus sapidus.

Science.gov (United States)

Plagemann, Ina; Krings, Ulrich; Berger, Ralf G

2014-01-01

The lipoxygenase LOX(Psa) 1 of Pleurotus sapidus, originally investigated because of its ability to oxidize (+)-valencene to the valuable grapefruit aroma (+)-nootkatone, was isolated from the peptidase-rich lyophilisate using a three-step purification scheme including preparative isoelectric focusing and chromatographic techniques. Nano-liquid chromatography electrospray ionization tandem mass spectrometry (nLC-ESI-MS/MS) of the purified enzyme and peptide mass fingerprint analysis gave 38 peptides of the lipoxygenase from P. sapidus. Nearly 50% of the 643 amino acids long sequence encoded by the cDNA was covered. Both terminal peptides of the native LOX(Psa) 1 were identified by de novo sequencing, and the postulated molecular mass of 72.5 kDa was confirmed. With linoleic acid as the substrate, the LOX(Psa)1 showed a specific activity of 113 U mg(-1) and maximal activity at pH 7.0 and 30 degrees C, respectively.

Correlation between MRS and serum PSA in the diagnosis of local recurrence after radical prostatectomy

Directory of Open Access Journals (Sweden)

Ghafuri M

2012-08-01

Full Text Available Background: Multifocality, multicentricity and extension beyond the prostate capsule are all characteristics of prostatic adenocarcinoma that may escape diagnosis by conventional CT scanning or MRI. This study was designed to assess the diagnostic value of magnetic resonance spectroscopy (MRS in prostatic carcinoma and its compatibility with prostatic specific antigen (PSA as the conventional method.Methods: In this cross-sectional study, we recruited 139 patients with previous radical prostatectomy referring to Radiology department of Hazrate-e-Rasul Hospital during the first half of 2011 for the evaluation of local recurrence. Traditionally, local recurrence is defined as serum PSA concentration >0.2 ng/dl. We used 1.5-tesla Siemens Avanto MRI unit with endorectal coil and measured creatine, choline and citrate levels before calculating choline-creatine/citrate ratio. Correlation between MRS findings with PSA concentration was evaluated in regards to the multiple levels of the previously mentioned ratio.Results: Local recurrence was found in 107 (77% patients based on PSA levels. The mean values for serum PSA levels and creatine-choline/citrate ratio were significantly different in patients with and without local recurrence. Creatine-choline/citrate ratios greater than 50, 100 and 150 (as different cut-off points of recurrence were respectively seen in 104, 102 and 97 patients and agreement ratio between MRS and PSA in these levels were 94.1%, 94.4% and 85.1%, respectively. Correlation coefficient between these two methods was 0.481.Conclusion: MRS is a valuable tool for evaluating recurrence inpatients with prostate cancer treated by radical prostatectomy and it is in good agreement with serum PSA levels.

Impact of PSA density of transition zone as a potential parameter in reducing the number of unnecessary prostate biopsies in patients with psa levels between 2.6 and 10.0 ng/mL.

Science.gov (United States)

Castro, Hugo A Socrates; Iared, Wagner; Santos, José Eduardo Mourão; Solha, Raphael Sandes; Shigueoka, David Carlos; Ajzen, Sergio Aron

2018-04-10

To assess the accuracy of prostate-specific antigen (PSA) adjusted for the transition zone volume (PSATZ) in predicting prostate cancer by comparing the ability of several PSA parameters in predicting prostate cancer in men with intermediate PSA levels of 2.6 - 10.0 ng/mL and its ability to reduce unnecessary biopsies. This study included 656 patients referred for prostate biopsy who had a serum PSA of 2.6 - 10.0 ng/mL. Total prostate and transition zone volumes were measured by transrectal ultrasound using the prolate ellipsoid method. The clinical values of PSA, free-to-total (F/T) ratio, PSA density (PSAD) and PSATZ for the detection of prostate cancer were calculated and statistical comparisons between biopsy-positive (cancer) and biopsy-negative (benign) were conducted. Cancer was detected in 172 patients (26.2%). Mean PSA, PSATZ, PSAD and F/T ratio were 7.5 ng/mL, 0.68 ng/mL/cc. 0.25 ng/mL/cc and 0.14 in patients with prostate cancer and 6.29 ng/mL, 0.30 ng/mL/cc, 0.16 ng/mL/cc and 0.22 in patients with benign biopsies, respectively. ROC curves analysis demonstrated that PSATZ had a higher area under curve (0,838) than F/T ratio (0,806) (PPSA. Compared to other PSA related parameters, it was better in differentiating between prostate cancer and benign prostatic enlargement. Also, PSATZ could reduce a significant number of unnecessary biopsies. Copyright® by the International Brazilian Journal of Urology.

Computerized systems for high level information processing and decision making in the field of PSA

International Nuclear Information System (INIS)

Kafka, P.; Kunitz, H.

1990-01-01

A comprehensive review of Probabilistic Safety Assessment (PSA) related program packages is made. Three fields in methodological succession are covered: plant modeling, data quantification procedures and decision-making support. Packages for fault tree construction and minimal cut sets evaluation are referred to and the performances of three of them: RALLY, ORCHARD and SALP-PC, are discussed and compared. Notions on the raw data sources are presented and the Nuclear Computerized Library for Assessing Reactor Reliability (NUCLARR) is given as an example for data base management system generating PSA data. Aggregated risk models for support in safety assessment, plant operation and accident management (SARA, ESSM, PRISIM) are cited. Examples of systems supporting 'living PSA' (SAIS, SUPER-NET, LESSEPS 1300, NUPRA, SPSA) are given. The concluding remarks outline the state-of-the-art developments of computerized systems for reliability analyses. 1 fig., 1 tab., 51 refs. (R.Ts)

Research on the improvement of nuclear safety -Development of level 2 PSA technology-

International Nuclear Information System (INIS)

Jin, Yung Hoh; Park, Soo Yong; Kim, Si Dal; Song, Yong Man; An, Kwang Il

1995-07-01

The objective of this project is the development of the computer code system for level 2 probabilistic safety assessment (PSA) of nuclear power plants. The scope of the project can be divided into three areas. The first area is to develop the computer code (CONPAS) which can quantify the accident progression event trees. CONPAS beta version has been developed this year and it is comprised of two modules: (1) EDITOR for generating the event tree logic diagrams and (2) QUANTIFICATION for event tree quantification and for additional use of the calculated results. Comparing with the existing computer code, the present code provides a flexible code reusability and user interface, convenient edition of logic diagram, data operation, and systematic quantification of the results. The methodology development of containment structural analysis is the second area. Over twenty large dry PWR containments, the database for containment failure mode and pressure has been constructed and the simplified fragility model has been proposed to calculate the containment failure probability. They will be used as an important input not only in the containment analysis but also in the source term analysis. The last one is to develop the source term analysis methodology which will be used to characterize the source term release for various accidents. One generic parametric equation for PWR and BWR has been composed and parametric database of 6 nuclear plants (4 PWR plants and 2 BWR plants) has been established whose characteristics is then analyzed through the comparison of parameter and data difference among plants. In addition, the characteristics of parameters themselves have been also investigated and the complemental idea of the parametric data base has been briefly suggested. 50 figs, 43 tabs, 50 refs. (Author)

Research on the improvement of nuclear safety -Development of level 2 PSA technology-

Energy Technology Data Exchange (ETDEWEB)

Jin, Yung Hoh; Park, Soo Yong; Kim, Si Dal; Song, Yong Man; An, Kwang Il [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-07-01

The objective of this project is the development of the computer code system for level 2 probabilistic safety assessment (PSA) of nuclear power plants. The scope of the project can be divided into three areas. The first area is to develop the computer code (CONPAS) which can quantify the accident progression event trees. CONPAS beta version has been developed this year and it is comprised of two modules: (1) EDITOR for generating the event tree logic diagrams and (2) QUANTIFICATION for event tree quantification and for additional use of the calculated results. Comparing with the existing computer code, the present code provides a flexible code reusability and user interface, convenient edition of logic diagram, data operation, and systematic quantification of the results. The methodology development of containment structural analysis is the second area. Over twenty large dry PWR containments, the database for containment failure mode and pressure has been constructed and the simplified fragility model has been proposed to calculate the containment failure probability. They will be used as an important input not only in the containment analysis but also in the source term analysis. The last one is to develop the source term analysis methodology which will be used to characterize the source term release for various accidents. One generic parametric equation for PWR and BWR has been composed and parametric database of 6 nuclear plants (4 PWR plants and 2 BWR plants) has been established whose characteristics is then analyzed through the comparison of parameter and data difference among plants. In addition, the characteristics of parameters themselves have been also investigated and the complemental idea of the parametric data base has been briefly suggested. 50 figs, 43 tabs, 50 refs. (Author).

Development of seismic PSA methodology at JAERI

International Nuclear Information System (INIS)

Muramatsu, K.; Ebisawa, K.; Matsumoto, K.; Oikawa, T.; Kondo, M.

1995-01-01

The Japan Atomic Energy Research Institute (JAERI) is developing a methodology for seismic probabilistic safety assessment (PSA) of nuclear power plants, aiming at providing a set of procedures, computer codes and data suitable for performing seismic PSA in Japan. In order to demonstrate the usefulness of JAERI's methodology and to obtain better understanding on the controlling factors of the results of seismic PSAs, a seismic PSA for a BWR is in progress. In the course of this PSA, various improvements were made on the methodology. In the area of the hazard analysis, the application of the current method to the model plant site is being carried out. In the area of response analysis, the response factor method was modified to consider the non-linear response effect of the building. As for the capacity evaluation of components, since capacity data for PSA in Japan are very scarce, capacities of selected components used in Japan were evaluated. In the systems analysis, the improvement of the SECOM2 code was made to perform importance analysis and sensitivity analysis for the effect of correlation of responses and correlation of capacities. This paper summarizes the recent progress of the seismic PSA research at JAERI with emphasis on the evaluation of component capacity and the methodology improvement of systems reliability analysis. (author)

A method for using expert judgement in PSA

International Nuclear Information System (INIS)

Pulkkinen, U.; Holmberg, J.

1997-03-01

The report discusses an expert judgement methodology development for applications at all levels of probabilistic safety assessment (PSA). The main applications are expected to be at PSA-levels 1 and 2. The method consists of several phases, including the selection and training of the experts, elicitation of experts' judgements, probabilistic modeling and combination of experts' judgements and documentation of the judgement process. The expert training and elicitation process is rather similar to that applied in the NUREG-1150 study. The combination of experts judgements is based on a Bayesian framework utilizing hierarchic models. The posterior distributions of the variables under analysis can be interpreted as a Bayesian counterpart of the combined or aggregated (consensus) distributions, and they are determined by applying Markov chain Monte-Carlo methods. The properties of the method are illustrated by some simple examples. The method is tested in a case study belonging to the benchmark exercise on the use of expert judgement in level 2 PSA, organized as a concerted action of European Commission Fourth Framework Programme on Nuclear Fission Safety. (14 refs.)

Management and organisational factors in PSA; Organisations- und Management-Faktoren in der PSA

Energy Technology Data Exchange (ETDEWEB)

Balfanz, H.P. [TUEV Nord e.V., Hamburg (Germany)

1999-04-01

The constraints of PSA are increasingly considered with increasing application of PSA for the safety management of nuclear power plants (see US-NRC, 'Risk Informed Regulation', NRC-1). There is a vivid international discourse about the applicability of the variables of plant management and organisation in PSAs, which has lead to a great variety of research activities into this matter (see PSAM 4). This paper here summarizes the current state of progress of research work and discusses the applicability of results. The studies for comparative assessment of methodology and results were performed by the TUeV Nord under the roof of the BMU/BfS-sponsored project SR 2260, ''Further development of probabilistic methods for nuclear power plant safety assessment. (orig./CB) [German] Mit zunehmender Anwendung der PSA (Probabilistische Sicherheitsanalyse) im Sicherheitsmanagement von KKW (vergl. US-NRC, Einfuehrung des Konzepts 'Risk Informed Regulation' NRC-1) gewinnt die Beachtung der Grenzen der PSA zusaetzliche Bedeutung. International ist eine intensive Diskussion ueber die Moeglichkeiten einer Einbindung der Einflussgroesse von Organisation und Management in der PSA zu verzeichnen und wird belegt durch vielfaeltige Forschungs- und Entwicklungsarbeiten (vergl. PSAM 4). Dieser Beitrag setzt sich in erster Linie mit diesem Entwicklungsstand auseinander und diskutiert seinen Anwendungsstand fuer die PSA. Die hierzu vom TUeV Nord durchgefuehrten Arbeiten basieren auf dem BMU/BfS-Vorhaben SR 2260, 'Weiterentwicklung probabilistischer Methoden zur Sicherheitsbeurteilung von KKW'. (orig.)

STD Awareness PSA - College 1 (:30)

Centers for Disease Control (CDC) Podcasts

2010-04-22

This PSA, targeted to college-aged youth and young adults, encourages listeners to get tested for STDs.  Created: 4/22/2010 by Centers for Disease Control and Prevention (CDC).   Date Released: 4/22/2010.

PSA testing anxiety, psychological morbidity, and PSA utility in the management of prostate cancer.

OpenAIRE

Micsunescu, Anamaria Elia

2017-01-01

Anecdotal reports from urologists and medical oncologists have suggested that patients with prostate cancer (PCa) often present with anxiety related to ongoing monitoring of their PSA levels as part of their disease management. The purpose of the current study, therefore, was to determine the prevalence and severity of prostate specific antigen (PSA) testing anxiety in a population of patients with either localised or metastatic PCa living in Australia. Other aspects of psychological morbidit...

Detection of prostate cancer with complexed PSA and complexed/total PSA ratio - is there any advantage?

OpenAIRE

Strittmatter, F; Stieber, P; Nagel, D; Füllhase, C; Walther, S; Stief, CG; Waidelich, R

2011-01-01

Abstract Objective To evaluate the performance of total PSA (tPSA), the free/total PSA ratio (f/tPSA), complexed PSA (cPSA) and the complexed/total PSA ratio (c/tPSA) in prostate cancer detection. Methods Frozen sera of 442 patients have been analysed for tPSA, free PSA (fPSA) and cPSA. 131 patients had prostate cancer and 311 patients benign prostatic hyperplasia. Results Differences in the distribution of the biomarkers were seen as follows: tPSA, cPSA and c/tPSA were significantly higher i...

Endogenous and exogenous testosterone and the risk of prostate cancer and increased prostate-specific antigen (PSA) level: a meta-analysis.

Science.gov (United States)

Boyle, Peter; Koechlin, Alice; Bota, Maria; d'Onofrio, Alberto; Zaridze, David G; Perrin, Paul; Fitzpatrick, John; Burnett, Arthur L; Boniol, Mathieu

2016-11-01

To review and quantify the association between endogenous and exogenous testosterone and prostate-specific antigen (PSA) and prostate cancer. Literature searches were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Prospective cohort studies that reported data on the associations between endogenous testosterone and prostate cancer, and placebo-controlled randomized trials of testosterone replacement therapy (TRT) that reported data on PSA and/or prostate cancer cases were retained. Meta-analyses were performed using random-effects models, with tests for publication bias and heterogeneity. Twenty estimates were included in a meta-analysis, which produced a summary relative risk (SRR) of prostate cancer for an increase of 5 nmol/L of testosterone of 0.99 (95% confidence interval [CI] 0.96, 1.02) without heterogeneity (I² = 0%). Based on 26 trials, the overall difference in PSA levels after onset of use of TRT was 0.10 ng/mL (-0.28, 0.48). Results were similar when conducting heterogeneity analyses by mode of administration, region, age at baseline, baseline testosterone, trial duration, type of patients and type of TRT. The SRR of prostate cancer as an adverse effect from 11 TRT trials was 0.87 (95% CI 0.30; 2.50). Results were consistent across studies. Prostate cancer appears to be unrelated to endogenous testosterone levels. TRT for symptomatic hypogonadism does not appear to increase PSA levels nor the risk of prostate cancer development. The current data are reassuring, although some caution is essential until multiple studies with longer follow-up are available. © 2016 The Authors BJU International © 2016 BJU International Published by John Wiley & Sons Ltd.

Experiences of Uncertainty in Men With an Elevated PSA.

Science.gov (United States)

Biddle, Caitlin; Brasel, Alicia; Underwood, Willie; Orom, Heather

2015-05-15

A significant proportion of men, ages 50 to 70 years, have, and continue to receive prostate specific antigen (PSA) tests to screen for prostate cancer (PCa). Approximately 70% of men with an elevated PSA level will not subsequently be diagnosed with PCa. Semistructured interviews were conducted with 13 men with an elevated PSA level who had not been diagnosed with PCa. Uncertainty was prominent in men's reactions to the PSA results, stemming from unanswered questions about the PSA test, PCa risk, and confusion about their management plan. Uncertainty was exacerbated or reduced depending on whether health care providers communicated in lay and empathetic ways, and provided opportunities for question asking. To manage uncertainty, men engaged in information and health care seeking, self-monitoring, and defensive cognition. Results inform strategies for meeting informational needs of men with an elevated PSA and confirm the primary importance of physician communication behavior for open information exchange and uncertainty reduction. © The Author(s) 2015.

Use of simplified PSA studies in support of the ASTRID design process

International Nuclear Information System (INIS)

Gauthe, P.; Curnier, F.; Bertrand, F.; Vincon, L.; Jouve, S.; Balmain, M.; Rychkov, V.; Banchieri, Y.

2012-01-01

In the framework of the French Act of 28 June 2006 about nuclear materials and waste management, a GEN IV and actinides incineration demonstration prototype is to be commissioned in the 2020 decade. In this objective a prototype called ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) is proposed to demonstrate the progress made in SFR technology at an industrial scale by qualifying innovative options, some of which still remain open in the areas requiring improvements, especially safety and operability. More specifically, we aim for a level of safety that is at least equivalent to that of the EPR (third generation), with improvements made in SFR-specific fields. The integration of safety issues in the early phase of the design of ASTRID is necessarily expected. For this purpose, CEA and its partners AREVA and EDF have planned to perform a level-1 PSA to support and orientate the preliminary design of ASTRID reactor. This paper presents the PSA approach and current studies for the assessment of safety systems and the future work to be done for the 2012-2014 period. The preliminary preparation of PSA studies is presented: objectives and scope of the early design phase PSA, definition of core damage states, selection and grouping of initiating events, assessment of safety functions and related systems. Work under progress is also presented: modelling of event trees, construction of fault trees of safety systems, transient calculations of accident sequences with the CATHARE2 code and reliability data assessment. Main objectives of a level-1 PSA performed at conceptual design stage are an early assessment of the safety architecture of the reactor and findings about the most effective areas for improvement, but also the identification of dominant accident sequences and comparison with alternative designs. After the elaboration of a simplified level-1 PSA model for nominal state and main internal initiators, various design alternatives will be

Generation of monoclonal antibodies against prostate specific antigen (PSA) for the detection of PSA and its purification

International Nuclear Information System (INIS)

Acevedo Castro, Boris Ernesto

2012-01-01

The prostate cancer in Cuba is a problem of health (2672 diagnosed cases and 2769 deaths in 2007). Various diagnostic methods have been implemented for the detection and management of this disease, emphasizing among them (PSA) prostate-specific antigen serological determination. At this work was generated and characterized a panel of 11 antibodies (AcMs) monoclonal IgG1 detected with high affinity described major epitopes of the PSA, both in solution and attached to the test plate. From the panel obtained AcMs was the standardization of an essay type ELISA for the detection of serum total PSA (associated and free) equimolar, based on antibody monoclonal CB-PSA.4 in the coating and the CB-PSA.9 coupled with biotin as liner, with a detection limit of 0.15 ng/mL. Similarly, standardized system for detection in serum free PSA, based on the AcMs CB-PSA.4 (coating) and CB-PSA.2 coupled with biotin (liner), with a detection limit of 0.5 ng/mL. Finally, with the purpose of using PSA as standard in trials type ELISA, developed a simple method of inmunopurificación based on the AcM, CB-PSA.2, which was obtained the PSA with a purity exceeding 90%. Immunoassay Centre on the basis of the AcMs panel and the results of this study, developed and recorded two diagnostic systems for the detection of PSA in human serum. (author)

Purification of PSA from human semen

International Nuclear Information System (INIS)

Venkatesh, M.

1997-01-01

Full text: 1. Human seminal plasma collected from many volunteers are pooled and passed through a column of phenyl sepharose equilibrated with 1.25 M ammonium sulphate. Elution is carried out with 1.25 M ammonium sulphate initially, to remove the bulk non-adsorbing proteins. Gradient elution of the absorbed proteins with 0.01 M Tris-HCl, 0.25 M NaCl, pH 7.0 buffer gives a sharp peak containing PSA. At each stage, PSA has to be identified by an independent method such as immunodiffusion or an immunoassay. 2. The absorbed protein peak containing PSA is then lyophilised, redissolved in Tris-HCl buffer and chromatographed in a Superdex-75 or Sephadex-75 column. The absorbed proteins elute out as multiple peaks and PSA is eluted as a sharp peak.At each stage, PSA has to be identified by an independent method such as immunodiffusion or an immunoassay. 3. Step 2 is repeated for better purity. 4. The PSA peak is lyophilised, dissolved in Tris-HCl buffer without NaCl and further purified on an ion exchange column (either anion or cation exchange columns such as DEAE Sephadex or CM-Sephadex or Mono Q). Gradient elution using Tris-HCl buffer without NaCl and Tris-HCl buffer with 0.25 M NaCl resulted in a sharp pure PSA peak (homogenous, sharp single band on SDS-PAGE). This procedure is based on that reported by Wang et al., Oncology, 39,1,1982

Putting PSA to work

International Nuclear Information System (INIS)

Gubler, R.; Gomez-Cobo, A.

1998-01-01

The IAEA has, during the last three years, been working intensively on PSA applications. The draft TECDOC prepared during these activities, ''PSA Applications'' is summarized in this paper. Actual events at nuclear facilities provide an important basis to compare PSAs with reality. PSA based operational event analysis therefore can be used to evaluate the importance of operational events from a risk perspective but also can contribute to validating and enhancing PSAs and to continuously check whether or not the PSA models are adequate, appropriate and complete. The work of the IAEA in this area is therefore summarized as well. In a companion paper, titled ''Towards a credible PSA fit for applications'', two specific aspects regarding the quality of the PSA to be used are discussed in detail, namely the Living PSA concept, which ensures that the PSA reflects actual design and operational features and Quality Assurance for PSA. (author)

Development of a PSA information management system

International Nuclear Information System (INIS)

Ho, Seok; Dong Kyu, Kim; Sun Koo, Kang

2007-01-01

In general, Probabilistic Safety Agreement (PSA) is a very complicated work that uses and generates a lot of resources such as reports, procedures, drawings, assumptions, calculation sheets, PSA model, and so on. In many PSAs, however, the data, materials and knowledge considered and generated during performing PSA are scattered in many documents so that overall structure of PSA and information relationship between documents and models cannot easily be understood. To organize and manage all documents related to PSA, to capture knowledge of analysts, and finally to improve the quality of PSA, a PSA information management system (PIMS) was developed. The PIMS can manage all the documents of a PSA in a database and connect the causal relation between one information to another in the scattered documents via link. The PIMS can manage all the assumptions and technical basis used in PSA, and it can keep the record of the design changes the revision of PSA model. It can also control the review results of PSA models. The link of the PIMS can explicitly describe and reveal the expertise of the PSA analysts, and it enables the users to capture the knowledge and to understand the structure and contents of a PSA with ease. We are planning to apply the PIMS to the PSA of Shin Kori Units 1 and 2 as feasibility study and then to all the PSAs of the nuclear power plants in Korea. The PIMS is expected to contribute to enhancing the quality and confidence of PSA and reducing the efforts and costs of maintenance and update of PSA. (authors)

Development of a PSA information management system

Energy Technology Data Exchange (ETDEWEB)

Ho, Seok; Dong Kyu, Kim; Sun Koo, Kang [Korea Power Engineering Company, Inc (Korea, Republic of)

2007-07-01

In general, Probabilistic Safety Agreement (PSA) is a very complicated work that uses and generates a lot of resources such as reports, procedures, drawings, assumptions, calculation sheets, PSA model, and so on. In many PSAs, however, the data, materials and knowledge considered and generated during performing PSA are scattered in many documents so that overall structure of PSA and information relationship between documents and models cannot easily be understood. To organize and manage all documents related to PSA, to capture knowledge of analysts, and finally to improve the quality of PSA, a PSA information management system (PIMS) was developed. The PIMS can manage all the documents of a PSA in a database and connect the causal relation between one information to another in the scattered documents via link. The PIMS can manage all the assumptions and technical basis used in PSA, and it can keep the record of the design changes the revision of PSA model. It can also control the review results of PSA models. The link of the PIMS can explicitly describe and reveal the expertise of the PSA analysts, and it enables the users to capture the knowledge and to understand the structure and contents of a PSA with ease. We are planning to apply the PIMS to the PSA of Shin Kori Units 1 and 2 as feasibility study and then to all the PSAs of the nuclear power plants in Korea. The PIMS is expected to contribute to enhancing the quality and confidence of PSA and reducing the efforts and costs of maintenance and update of PSA. (authors)

A Study on the Risk Reduction Effect by MLCS (Mid-loop Level Control System) of EUAPR using the Low-Power and Shutdown PSA Result

International Nuclear Information System (INIS)

Lee, Keunsung; Choi, Sunmi; Kim, Eden

2016-01-01

The EU-APR design has been developed in order to expand and diversify the global nuclear power market of APR1400. For the improvement of shutdown risk for the EUAPR, the mid-loop level control system (MLCS) is considered during mid-loop operation for the EU-APR, which is not incorporated into SKN 3 and 4 (APR1400 Type) in Korea. Commonly, the risk associated with the NPP can be identified through the PSA. Thus, this paper discusses the low power and shutdown (LPSD) risk reduction effect by MLCS using the Low-Power and Shutdown PSA Result. LPSD level 1 PSA models for EU-APR have been developed. The risk reduction effect by MLCS is discussed. Because the loss of shutdown cooling function during mid-loop is one of the most vulnerable events, the MLCS have a significant influence on CDF in LPSD PSA. The shutdown risk of domestic power plants would likely be reduced if the MLCS is adopted in all operating NPPs in Korea during the mid-loop operation. It is expected that this work will contribute to reduce shutdown risk of domestic power plants

The clinical value of serum PSA and PAP determinations in prostate cancer patients

International Nuclear Information System (INIS)

Zeng Lei; Yu Renbo; Du Guowei; Pang Baozhong

2001-01-01

Objective: To investigate the clinical value of serum PSA and PAP determinations in diagnosis of prostate cancer patients. Methods: The serum PSA and PAP levels of 98 prostate cancer patients, 45 prostate benign disease patients and 40 normal subjects were tested by IRMA. Results: The serum PSA and PAP levels of prostate cancer patients were significantly higher than those in prostate benign disease patients and normal controls (P < 0.01). The diagnostic sensitivity and specificity of serum PSA for prostate cancer were 93.9% and 93.3% respectively. The diagnostic sensitivity and specificity of serum PAP for prostate cancer were 71.4% and 91.1% respectively. Conclusion: The determination of serum PSA and PAP was of high clinical value for diagnosis of early prostate cancer. It could be used as an important reference parameter for the clinical staging, follow-up of treatment result and prediction of prognosis

PSA-operations synergism for the advanced test reactor shutdown operations PSA

International Nuclear Information System (INIS)

Atkinson, S.A.

1996-01-01

The Advanced Test Reactor (ATR) Probabilistic Safety Assessment (PSA) for shutdown operations, cask handling, and canal draining is a successful example of the importance of good PSA-operations synergism for achieving a realistic and accepted assessment of the risks and for achieving desired risk reduction and safety improvement in a best and cost-effective manner. The implementation of the agreed-upon upgrades and improvements resulted in the reductions of the estimated mean frequency for core or canal irradiated fuel uncovery events, a total reduction in risk by a factor of nearly 1000 to a very low and acceptable risk level for potentially severe events

Use of PSA Level 2 analysis for improving containment performance. Report of a technical committee meeting

International Nuclear Information System (INIS)

1998-03-01

In order to discuss and exchange experience on different aspects of methods associated with Level 2 PSA and its applications for improving containment performance, the IAEA held a Technical Committee meeting in Vienna in December 1996. The meeting, which was attended by 26 participants from 20 Member States, provided a broad forum for discussion. The meeting addressed the issues related to the actual performance of Level 2 PSA studies as well as the insights gained from applications to improve containment performance. Particular attention was given to studies and applications for WWER type reactors, for which Level 2 work is still in its early stages, and for channel type reactors where modelling of accident progression is complex and significantly different from vessel type light water reactors. This TECDOC contains the papers presented at the meeting and the results of extensive discussions which were held in specific working groups

Applications of probabilistic safety assessment (PSA) for nuclear power plants

International Nuclear Information System (INIS)

2001-02-01

This report, which compiles information on a comprehensive set of PSA applications in the areas of NPP design, operation, and accident mitigation and management, is the culmination of an IAEA project on PSA Applications and Tools to Improve NPP Safety. In this regard, the Technical Committee Meeting (TCM) held in Madrid in February 1998 allowed participants to review and provide very valuable comments for this report. Several important facts related to PSA and its applications were highlighted during this TCM: living PSAs are the basis for the risk informed approach to decision making; development and use of safety/risk monitors as tools for configuration management is spreading fast; the different uses of PSA to support NPP testing and maintenance planning and optimization are amongst the most widespread PSA applications; plant specific PSAs are being used to support the safety upgrading programmes of plants built to earlier standards; not all countries have a regulatory framework for the use of the probabilistic approach in decision making. Some countries are still far from 'risk-informed' regulation, and this means that there is still considerable work ahead, both for regulators and utilities, to clarify approaches, to establish a framework and to reach a common understanding in relation to the use of PSA in decision making. This report is based on the premise that the use of PSA can provide useful information for the decision maker. This report is intended to provide an overview of current PSA applications. Section 2 addresses the PSA application process, outlines the general requirements for PSA tools and provides a discussion on PSA aspects such as PSA level, scope and level of detail, which have to be considered when planning/performing PSA applications. Section 3 discusses the technical aspects of individual applications and is divided into three parts. Section 3.1 is dedicated to the design related PSA applications. The second part of Section 3 considers

Isotope and Patient Age Predict for PSA Spikes After Permanent Prostate Brachytherapy

International Nuclear Information System (INIS)

Bostancic, Chelsea; Merrick, Gregory S.; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah; Galbreath, Robert; Lief, Jonathan; Gutman, Sarah E.

2007-01-01

Purpose: To evaluate prostate-specific antigen (PSA) spikes after permanent prostate brachytherapy in low-risk patients. Methods and Materials: The study population consisted of 164 prostate cancer patients who were part of a prospective randomized trial comparing 103 Pd and 125 I for low-risk disease. Of the 164 patients, 61 (37.2%) received short-course androgen deprivation therapy. The median follow-up was 5.4 years. On average, 11.1 post-treatment PSA measurements were obtained per patient. Biochemical disease-free survival was defined as a PSA level of ≤0.40 ng/mL after nadir. A PSA spike was defined as an increase of ≥0.2 ng/mL, followed by a durable decline to prespike levels. Multiple parameters were evaluated as predictors for a PSA spike. Results: Of the 164 patients, 44 (26.9%) developed a PSA spike. Of the 46 hormone-naive 125 I patients and 57 hormone-naive 103 Pd patients, 21 (45.7%) and 8 (14.0%) developed a PSA spike. In the hormone-naive patients, the mean time between implantation and the spike was 22.6 months and 18.7 months for 125 I and 103 Pd, respectively. In patients receiving neoadjuvant androgen deprivation therapy, the incidence of spikes was comparable between isotopes ( 125 I 28.1% and 103 Pd 20.7%). The incidence of spikes was substantially different in patients 125 I and/or <65 years of age. Differences in isotope-related spikes are most pronounced in hormone-naive patients

The relationship between serum PSA, six sex hormones and the benign or malignant prostate diseases

International Nuclear Information System (INIS)

Xu Yancun

2008-01-01

In order to study clinical significance of serum prostate-specific antigen (PSA), free prostate specific antigen (PSA), f/tPSA and six sex hormones in prostate diseases, the serum levels of PSA, fPSA, f/tPSA, T, P, E 2 , PRL, LH and FSH in 72 cases of hyperplasia of prostate patients and 40 patients with prostate cancer were determined by RIA. The results showed that the serum levels of T, E 2 , PRL, LH, FSH in the BPH Group were significantly lower than those of in Pca group, the serum level of P in Pca group were significantly lower than those in BPH group; the levels of fPSA and f/tPSA ratio in BPH Group were significantly higher than those in Pca group. The results suggest that benign and malignant prostate disease (BPH and Pca) was related with the hormone imbalance. The serum total PSA and fPSA can be regarded as important indicators in the diagnosis of BPH and Pea. The combined determination of PSA, fPSA and f/tPSA may improve the diagnostic accuracy of Pca. (authors)

Re-examining Prostate-specific Antigen (PSA) Density: Defining the Optimal PSA Range and Patients for Using PSA Density to Predict Prostate Cancer Using Extended Template Biopsy.

Science.gov (United States)

Jue, Joshua S; Barboza, Marcelo Panizzutti; Prakash, Nachiketh S; Venkatramani, Vivek; Sinha, Varsha R; Pavan, Nicola; Nahar, Bruno; Kanabur, Pratik; Ahdoot, Michael; Dong, Yan; Satyanarayana, Ramgopal; Parekh, Dipen J; Punnen, Sanoj

2017-07-01

To compare the predictive accuracy of prostate-specific antigen (PSA) density vs PSA across different PSA ranges and by prior biopsy status in a prospective cohort undergoing prostate biopsy. Men from a prospective trial underwent an extended template biopsy to evaluate for prostate cancer at 26 sites throughout the United States. The area under the receiver operating curve assessed the predictive accuracy of PSA density vs PSA across 3 PSA ranges (10 ng/mL). We also investigated the effect of varying the PSA density cutoffs on the detection of cancer and assessed the performance of PSA density vs PSA in men with or without a prior negative biopsy. Among 1290 patients, 585 (45%) and 284 (22%) men had prostate cancer and significant prostate cancer, respectively. PSA density performed better than PSA in detecting any prostate cancer within a PSA of 4-10 ng/mL (area under the receiver operating characteristic curve [AUC]: 0.70 vs 0.53, P PSA >10 mg/mL (AUC: 0.84 vs 0.65, P PSA density was significantly more predictive than PSA in detecting any prostate cancer in men without (AUC: 0.73 vs 0.67, P PSA increases, PSA density becomes a better marker for predicting prostate cancer compared with PSA alone. Additionally, PSA density performed better than PSA in men with a prior negative biopsy. Copyright © 2017 Elsevier Inc. All rights reserved.

The use of PSA in the French regulatory practice

International Nuclear Information System (INIS)

Mennesiez, H.

1994-01-01

The presentation gives a description of fundamental documents (since 1977-1978) through which have been set up in France probabilistic objectives, and PSAs, including shutdown states, performed for 900-1300 MWe PWR-type nuclear power plants. PSA developments and use, including fire PSA, level 2 and PSA for the future French-German European Pressurized Reactor (EPR) are also discussed

Long-term longitudinal changes in baseline PSA distribution and estimated prevalence of prostate cancer in male Japanese participants of population-based PSA screening.

Science.gov (United States)

Oki, Ryo; Ito, Kazuto; Suzuki, Rie; Fujizuka, Yuji; Arai, Seiji; Miyazawa, Yoshiyuki; Sekine, Yoshitaka; Koike, Hidekazu; Matsui, Hiroshi; Shibata, Yasuhiro; Suzuki, Kazuhiro

2018-04-26

Japan has experienced a drastic increase in the incidence of prostate cancer (PC). To assess changes in the risk for PC, we investigated baseline prostate specific antigen (PSA) levels in first-time screened men, across a 25-year period. In total, 72,654 men, aged 50-79, underwent first-time PSA screening in Gunma prefecture between 1992 and 2016. Changes in the distribution of PSA levels were investigated, including the percentage of men with a PSA above cut-off values and linear regression analyses comparing log 10 PSA with age. The 'ultimate incidence' of PC and clinically significant PC (CSPC) were estimated using the PC risk calculator. Changes in the age-standardized incidence rate (AIR) during this period were analyzed. The calculated coefficients of linear regression for age versus log 10 PSA fluctuated during the 25-year period, but no trend was observed. In addition, the percentage of men with a PSA above cut-off values varied in each 5-year period, with no specific trend. The 'risk calculator (RC)-based AIR' of PC and CSPC were stable between 1992 and 2016. Therefore, the baseline risk for developing PC has remained unchanged in the past 25 years, in Japan. The drastic increase in the incidence of PC, beginning around 2000, may be primarily due to increased PSA screening in the country. © 2018 UICC.

Characteristics Studies of 125I- and total PSA antibody's Binding with prostate specific antigen (PSA) in Human Uterus Tumors

International Nuclear Information System (INIS)

Al-Mudaffar, S.; Al-Salihi, J.

2005-01-01

Two groups of uterus tumors (benign and malignant) postmenopausal patients were used to investigate the presence of prostate specific antigen (PSA). Preliminary experiments were performed to follow the binding of '1 25 I-anti total PSA antibody with PSA in uterus tissues homogenates of the two groups with their corresponding antigen and found to be (8.8,7.1%) for benign and malignant tumors, respectively. An Immuno Radio Metric Assay (IRMA) procedure was developed for measuring PSA in benign and malignant uterus tumors homogenates. The optimum conditions of the binding of 125 I-anti total PSA antibody with PSA were as follows: PSA concentration (150,200 μg protein),tracer antibody concentration (125,250 μg protein), p H (7.6,7.2), temp (15,25?C) and time (1.5 hrs) for postmenopausal benign and malignant uterus tumors tissue homogenates, respectively. The use of different concentrations of Na + and Mg 2+ ions were shown to cause an increase in the binding at concentration of (125,75 mΜ) of Na 1+ ions (75,225 mΜ) of Mg 2+ ions for benign and malignant uterus tumors homogenates, respectively, while the use of different concentrations of urea and polyethylene glycol (PEG) Caused a decrease in the binding with the increase in the concentration of each of urea and PEG in the both cases

[Relationship between tumor volume and PSA recurrence after radical prostatectomy].

Science.gov (United States)

Hashimoto, Yasuhiro; Momose, Akishi; Okamoto, Akiko; Yamamoto, Hayato; Hatakeyama, Shingo; Iwabuchi, Ikuya; Yoneyama, Takahiro; Koie, Takuya; Kamimura, Noritaka; Ohyama, Chikara

2010-02-01

We examined whether the tumor volume (TV) is a good predictor of PSA recurrence after radical prostatectomy. Data were collected for 158 patients with clinically localized prostate cancer undergoing radical prostatectomy without neoadjuvant hormonal therapy in our hospital since April 2005 to September 2007. Along with the routine pathological assessment, TV was assessed in all prostatectomy specimens. PSA recurrence was defined as PSA levels of greater than 0.2 ng/ml. The TVs were 1.81+/-1.66 ml (mean +/-SD) ranging from 0.02 to 8.20 ml. The TV in cT1c was 1.77+/-1.64, and 1.89+/-1.72 ml in cT2 (not significant). Significant differences were observed between TV and pT. The TVs in pT2a, pT2b and pT3/4 were 0.54+/-0.54, 1.63+/-1.47 and 2.67+/-1.80 ml, respectively. The median follow-up period was 32.3 months (range from 15 to 45) after radical prostatectomy, and PSA recurrence was observed in 32 cases. Patients with smaller TV (TV TV (TV > or = 1.3 ml, 66.7%) with a significant difference atp TV, pT, Gleason Score (GS), and surgical margins. Significant differences were observed for GS, and surgical margins, but not for TV. Clinically organ-confined disease in Japanese patients with prostate cancer included various cancers from clinically insignificant to locally advanced ones. In our series, TV was not regarded as a predictor of PSA recurrence after radical prostatectomy.

Real-life experience of using conventional disease-modifying anti-rheumatic drugs (DMARDs) in psoriatic arthritis (PsA). Retrospective analysis of the efficacy of methotrexate, sulfasalazine, and leflunomide in PsA in comparison to spondyloarthritides other than PsA and literature review of the use of conventional DMARDs in PsA

Science.gov (United States)

Roussou, Euthalia; Bouraoui, Aicha

2017-01-01

Objective With the aim of assessing the response to treatment with conventional disease-modifying anti-rheumatic drugs (DMARDs) used in patients with psoriatic arthritis (PsA), data on methotrexate, sulfasalazine (SSZ), and leflunomide were analyzed from baseline and subsequent follow-up (FU) questionnaires completed by patients with either PsA or other spondyloarthritides (SpAs). Material and Methods A single-center real-life retrospective analysis was performed by obtaining clinical data via questionnaires administered before and after treatment. The indices used were erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Function Index (BASFI), wellbeing (WB), and treatment effect (TxE). The indices measured at baseline were compared with those measured on one occasion in a FU visit at least 1 year later. Results A total of 73 patients, 51 with PsA (mean age 49.8±12.8 years; male-to-female ratio [M:F]=18:33) and 22 with other SpAs (mean age 50.6±16 years; M:F=2:20), were studied. BASDAI, BASFI, and WB displayed consistent improvements during FU assessments in both PsA patients and controls in comparison to baseline values. SSZ exhibited better efficacy as confirmed by TxE in both PsA patients and controls. ESR and CRP displayed no differences in either the PsA or the SpA group between the cases before and after treatment. Conclusion Real-life retrospective analysis of three DMARDs used in PsA (and SpAs other than PsA) demonstrated that all three DMARDs that were used brought about improvements in BASDAI, BASFI, TxE, and WB. However, the greatest improvements at FU were seen with SSZ use in both PsA and control cohorts. PMID:28293446

PSA doubling time of prostate carcinoma managed with watchful observation alone

International Nuclear Information System (INIS)

Choo, Richard; DeBoer, Gerrit; Klotz, Lawrence; Danjoux, Cyril; Morton, Gerard C.; Rakovitch, Eileen; Fleshner, Neil; Bunting, Peter; Kapusta, Linda; Hruby, George

2001-01-01

Purpose: To study prostate-specific antigen (PSA) doubling time of untreated, favorable grade, prostate carcinoma. Methods and Materials: A prospective single-arm cohort study has been in progress to assess the feasibility of a watchful observation protocol with selective delayed intervention using clinical, histologic, or PSA progression as treatment indication in untreated, localized, favorable grade prostate adenocarcinoma (T1b-T2bN0 M0, Gleason Score ≤7, and PSA ≤15 ng/mL). Patients are conservatively managed with watchful observation alone, as long as they do not meet the arbitrarily defined disease progression criteria. Patients are followed regularly and undergo blood tests including PSA at each visit. PSA doubling time (Td) is estimated from a linear regression of ln(PSA) on time, assuming a simple exponential growth model. Results: As of March 2000, 134 patients have been on the study for a minimum of 12 months (median, 24; range, 12-52) and have a median frequency of PSA measurement of 7 times (range, 3-15). Median age is 70 years. Median PSA at enrollment is 6.3 (range, 0.5-14.6). The distribution of Td is as follows: 50 years, 27. The median Td is 5.1 years. In 44 patients (33%), Td is greater than 10 years. There was no correlation between Td and patient age, clinical T stage, Gleason score, or initial PSA level. Conclusion: Td of untreated prostate cancer varies widely. In our cohort, 33% have Td >10 years. Td may be a useful tool to guide treatment intervention for patients managed conservatively with watchful observation alone

PSA methodology

International Nuclear Information System (INIS)

Magne, L.

1996-01-01

The purpose of this text is first to ask a certain number of questions on the methods related to PSAs. Notably we will explore the positioning of the French methodological approach - as applied in the EPS 1300 1 and EPS 900 2 PSAs - compared to other approaches (Part One). This reflection leads to more general reflection: what contents, for what PSA? This is why, in Part Two, we will try to offer a framework for definition of the criteria a PSA should satisfy to meet the clearly identified needs. Finally, Part Three will quickly summarize the questions approached in the first two parts, as an introduction to the debate. 15 refs

Analytical tool for the periodic safety analysis of NPP according to the PSA guideline. Vol. 1

International Nuclear Information System (INIS)

Balfanz, H.P.; Boehme, E.; Musekamp, W.; Hussels, U.; Becker, G.; Behr, H.; Luettgert, H.

1994-01-01

The SAIS (Safety Analysis and Informationssystem) Programme System is based on an integrated data base, which consists of a plant-data and a PSA related data part. Using SAIS analyses can be performed by special tools, which are connected directly to the data base. Two main editors, RISA+ and DEDIT, are used for data base management. The access to the data base is done via different types of pages, which are displayed on a displayed on a computer screen. The pages are called data sheets. Sets of input and output data sheets were implemented, such as system or component data sheets, fault trees or event trees. All input information, models and results needed for updated results of PSA (Living PSA) can be stored in the SAIS. The programme system contains the editor KVIEW which guarantees consistency of the stored data, e.g. with respect to names and codes of components and events. The information contained in the data base are called in by a standardized users guide programme, called Page Editor. (Brunsbuettel on reference NPP). (orig./HP) [de

Atmospheric Dispersion Simulation for Level 3 PSA at Ulchin Nuclear Site using a PUFF model

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Jun; Han, Seok-Jung; Jeong, Hyojoon; Jang, Seung-Cheol [KAERI, Daejeon (Korea, Republic of)

2015-05-15

Air dispersion prediction is a key in the level 3 PSA to predict radiation releases into the environment for preparing an effective strategy for an evacuation as a basis of the emergency preparedness. To predict the atmospheric dispersion accurately, the specific conditions of the radiation release location should be considered. There are various level 3 PSA tools and MACSS2 is one of the widely used level 3 PSA tools in many countries including Korea. Due to the characteristics of environmental conditions in Korea, it should be demonstrated that environmental conditions of Korea nuclear sites can be appropriately illustrated by the tool. In Korea, because all nuclear power plants are located on coasts, sea and land breezes might be a significant factor. The objectives of this work is to simulate the atmospheric dispersion for Ulchin nuclear site in Korea using a PUFF model and to generate the data which can be used for the comparison with that of PLUME model. A nuclear site has own atmospheric dispersion characteristics. Especially in Korea, nuclear sites are located at coasts and it is expected that see and land breeze effects are relatively high. In this work, the atmospheric dispersion at Ulchin nuclear site was simulated to evaluate the effect of see and land breezes in four seasons. In the simulation results, it was observed that the wind direction change with time has a large effect on atmospheric dispersion. If the result of a PLUME model is more conservative than most severe case of a PUFF model, then the PLUME model could be used for Korea nuclear sites in terms of safety assessment.

Living PSA

International Nuclear Information System (INIS)

Evans, M.G.K.

1997-01-01

The aim of this presentation is to gain an understanding of the requirements for a PSA to be considered a Living PSA. The presentation is divided into the following topics: Definition; Planning/Documentation; Task Performance; Maintenance; Management. 4 figs

The inverse relationship between prostate-specific antigen (PSA) and obesity.

Science.gov (United States)

Aref, Adel; Vincent, Andrew D; O'Callaghan, Michael; Martin, Sean; Sutherland, Peter; Hoy, Andrew; Butler, Lisa M; Wittert, Gary

2018-06-25

Obese men have lower serum prostate-specific antigen (PSA) than comparably aged lean men, but the underlying mechanism remains unclear. The aim of this study was to determine the effect of obesity on PSA and the potential contributing mechanisms. A cohort of 1195 men aged 35 years and over at recruitment, with demographic, anthropometric (body mass index (BMI), waist circumference (WC)) and serum hormone (serum testosterone (T), estradiol (E2)), PSA and hematology assessments obtained over two waves was assessed. Men with a history of prostate cancer or missing PSA were excluded, leaving 970 men for the final analysis. Mixed-effects regressions and mediation analyses adjusting for hormonal and volumetric factors explore the potential mechanisms relating obesity to PSA. After adjusting for age, PSA levels were lower in men with greater WC (p=0.001). In a multivariable model including WC, age, E2/T and PlasV as predictors, no statistically significant associations were observed between with PSA and either WC (p=0.36) or PlasV (p=0.49), while strong associations were observed with both E2/T (pPSA (p=0.31), while when E2/T is a mediator; the ACME explained roughly 0.5 of the effect (pPSA levels in obese men, as compared to normal weight men, can be explained both by hormonal changes (elevated E2/T ratio) and haemodilution. Hormonal factors therefore represent a substantial but underappreciated mediating pathway.

The clinical study of serum PSA and fPSA assayed by CLIA in diagnosing prostate disease

International Nuclear Information System (INIS)

Xiong Jiang; Qian Xiaoyu; Ji Hong; Yang Su; Ding Ying; Zhu Ruisen; Chen Zhong

2003-01-01

The purpose of this study is to evaluate the clinical value of PSA (prostate specific antigen) and fPSA(free prostate specific antigen) in differentiating prostate disease. CLIA was used to quantitatively assay PSA, fPSA and fPSA/PSA in 30 cases of normal controls, 32 cases of prostate cancer patients and 76 cases of BPH patients. The result showed that if liminal value of PSA was set at 4 ng/mL, the diagnostic sensitivity and specificity of prostate cancer were 100% and 50.6% respectively. Meanwhile, if liminal value of fPSA/PSA set at 16% was added, the diagnostic sensitivity and specificity of prostate cancer were 100% and 85.3% respectively. It was concluded that the combining assay of PSA and fPSA could increase the diagnostic specificity of prostate cancer in a certain degree

A source term and risk calculations using level 2+PSA methodology

International Nuclear Information System (INIS)

Park, S. I.; Jea, M. S.; Jeon, K. D.

2002-01-01

The scope of Level 2+ PSA includes the assessment of dose risk which is associated with the exposures of the radioactive nuclides escaping from nuclear power plants during severe accidents. The establishment of data base for the exposure dose in Korea nuclear power plants may contribute to preparing the accident management programs and periodic safety reviews. In this study the ORIGEN, MELCOR and MACCS code were employed to produce a integrated framework to assess the radiation source term risk. The framework was applied to a reference plant. Using IPE results, the dose rate for the reference plant was calculated quantitatively

Can PSA Reflex Algorithm be a valid alternative to other PSA-based prostate cancer screening strategies?

Science.gov (United States)

Caldarelli, G; Troiano, G; Rosadini, D; Nante, N

2017-01-01

The available laboratory tests for the differential diagnosis of prostate cancer, are represented by the total PSA, the free PSA, and the free/total PSA ratio. In Italy most of doctors tend to request both total and free PSA for their patients even in cases where the total PSA doesn't justify the further request of free PSA, with a consequent growth of the costs for the National Health System. The aim of our study was to predict the saving in Euro (due to reagents) and reduction in free PSA tests, applying the "PSA Reflex" algorithm. We calculated the number of total PSA and free PSA exams performed in 2014 in the Hospital of Grosseto and, simulating the application of the "PSA Reflex" algorithm in the same year, we calculated the decrease in the number of free PSA requests and we tried to predict the Euro savings in reagents, obtained from this reduction. In 2014 in the Hospital of Grosseto 25,955 total PSA tests have been performed: 3,631 (14%) resulted greater than 10 ng / ml; 7,686 (29.6%) between 2 and 10 ng / ml; 14,638 (56.4%) lower than 2 ng / ml. The performed free PSA tests were 16904. Simulating the use of "PSA Reflex" algorithm, the free PSA tests would be performed only in cases with total PSA values between 2 and 10 ng / mL with a saving of 54.5% of free PSA exams and of 8,971 euros, only for reagents. Our study showed that the "PSA Reflex" algorithm is a valid alternative leading to a reduction of the costs. The estimated intralaboratory savings, due to the reagents, seem to be modest, however, they are followed by the additional savings due to the other diagnostic processes for prostate cancers.

PSA methodology

Energy Technology Data Exchange (ETDEWEB)

Magne, L

1997-12-31

The purpose of this text is first to ask a certain number of questions on the methods related to PSAs. Notably we will explore the positioning of the French methodological approach - as applied in the EPS 1300{sup 1} and EPS 900{sup 2} PSAs - compared to other approaches (Part One). This reflection leads to more general reflection: what contents, for what PSA? This is why, in Part Two, we will try to offer a framework for definition of the criteria a PSA should satisfy to meet the clearly identified needs. Finally, Part Three will quickly summarize the questions approached in the first two parts, as an introduction to the debate. 15 refs.

State of living PSA and further development

International Nuclear Information System (INIS)

1999-01-01

In October 1985 OECD-Principal Working Group (PWG 5) - Risk Assessment has initiated the Task Force 7 'Use of PSA in Nuclear Power Plant Management' to explore and report on the principles, characteristics, requirements and status of PSA oriented safety management. During this study, it became apparent that the utilisation of PSA techniques in nuclear plant safety management requires the development of supporting programmes to ensure that PSA models are being updated to reflect plant changes, and to direct their use towards the evaluation and determination of plant changes. These requirements also influence the software and hardware characteristics necessary to support the programme. This overall process is known as Living PSA. In this context OECD-PWG 5 has arranged international workshops on Living PSA application to support this development, to facilitate exchange of international experience and to summarise the state-of-the-art of L-PSA methodology. These activities were accompanied by following Task Groups of OECD-PWG 5 and the work results were published in state-of-the-art reports. According to the increasing development of Living PSA in the international field and its capacity to support plant safety management in a broad sense, OECD PWG 5 continues its work in setting up the Task Group 96-1 'State of Living PSA and Further Development' to clarify specific aspects of Living PSA. This report summarises the state of Living PSA in the international field based on the four Living PSA Workshops from 1988 to 1994 (Chapter 2) and the state of Reliability Data Collection based on the results of Task Group 12 'Reliability Data Collection and Analysis to Support PSA' and the two Data-Workshops from 1995 and 1998 (Chapter 3). The specific items of further development of Living PSA application as mentioned above are treated in Chapter 4. Chapter 5 gives a summary of the current state of Living PSA as well as outlook and recommendations of further development

Molecular Form Differences Between Prostate-Specific Antigen (PSA) Standards Create Quantitative Discordances in PSA ELISA Measurements

Science.gov (United States)

McJimpsey, Erica L.

2016-02-01

The prostate-specific antigen (PSA) assays currently employed for the detection of prostate cancer (PCa) lack the specificity needed to differentiate PCa from benign prostatic hyperplasia and have high false positive rates. The PSA calibrants used to create calibration curves in these assays are typically purified from seminal plasma and contain many molecular forms (intact PSA and cleaved subforms). The purpose of this study was to determine if the composition of the PSA molecular forms found in these PSA standards contribute to the lack of PSA test reliability. To this end, seminal plasma purified PSA standards from different commercial sources were investigated by western blot (WB) and in multiple research grade PSA ELISAs. The WB results revealed that all of the PSA standards contained different mass concentrations of intact and cleaved molecular forms. Increased mass concentrations of intact PSA yielded higher immunoassay absorbance values, even between lots from the same manufacturer. Standardization of seminal plasma derived PSA calibrant molecular form mass concentrations and purification methods will assist in closing the gaps in PCa testing measurements that require the use of PSA values, such as the % free PSA and Prostate Health Index by increasing the accuracy of the calibration curves.

Use of PSA to support accident management at NPPs

International Nuclear Information System (INIS)

Gomez Cobo, A.

1997-01-01

The presentation discusses the following: Overview of PSA level 2; Introduction: Framework; Accident Progression Phenomena in the Confinement/containment; Severe Accident Sequences; Examples; Results and Insights. Accident Management: Concepts; Process; Use of PSA to support Accident; Management

Method comparison for determination of the tumor markers AFP, CEA, PSA and free PSA between Immulite 2000 XPI and Dimension Vista 1500.

Science.gov (United States)

Zur, Berndt; Holdenrieder, Stefan; Walgenbach-Brünagel, Gisela; Albers, Eike; Stoffel-Wagner, Birgit

2012-01-01

For the Luminescent Oxygen Channeling Immunoassay (LOCI) technology as established for Dimension Vista 1500, assays have been developed for the serum tumor markers AFP, CEA, PSA and free PSA. We performed a method analysis for these parameters using the Immulite 2000 XPI. Determination of within-day and total imprecision of the methods was carried out according to CLSI guidelines with three serum pools. In addition, parallel measurements were performed with both systems in 1,871 routine serum samples and correlations were calculated. Calculated total imprecision of the three serum pools for AFP was 3.8 - 4.3%, for CEA 3.3 - 4.3%, for tPSA 3.6 - 4.0% and for fPSA it was 3.5 - 8.2%. Correlations of these markers across the entire value range were very good with the following correlation coefficients: 0.997 for AFP, 0.996 for CEA, 0.971 for tPSA and 0.988 for fPSA. While values for AFP and tPSA from both methods were comparable (slopes 1.02 and 1.01), lower values were measured for CEA and fPSA with the Dimension Vista (slopes 0.83 and 0.91). For AFP, a sample cluster with considerably higher values than with Dimension Vista was observed in the lower measurement range (CEA, tPSA and fPSA, as developed with the LOCI technology for the Dimension Vista, show good comparability with results obtained from the Immulite 2000 XPI. However, lower measurement ranges for CEA and fPSA as well as individual divergences, especially with AFP, must be taken into consideration in the event of method changeover.

Molecular Form Differences Between Prostate-Specific Antigen (PSA) Standards Create Quantitative Discordances in PSA ELISA Measurements

Science.gov (United States)

McJimpsey, Erica L.

2016-01-01

The prostate-specific antigen (PSA) assays currently employed for the detection of prostate cancer (PCa) lack the specificity needed to differentiate PCa from benign prostatic hyperplasia and have high false positive rates. The PSA calibrants used to create calibration curves in these assays are typically purified from seminal plasma and contain many molecular forms (intact PSA and cleaved subforms). The purpose of this study was to determine if the composition of the PSA molecular forms found in these PSA standards contribute to the lack of PSA test reliability. To this end, seminal plasma purified PSA standards from different commercial sources were investigated by western blot (WB) and in multiple research grade PSA ELISAs. The WB results revealed that all of the PSA standards contained different mass concentrations of intact and cleaved molecular forms. Increased mass concentrations of intact PSA yielded higher immunoassay absorbance values, even between lots from the same manufacturer. Standardization of seminal plasma derived PSA calibrant molecular form mass concentrations and purification methods will assist in closing the gaps in PCa testing measurements that require the use of PSA values, such as the % free PSA and Prostate Health Index by increasing the accuracy of the calibration curves. PMID:26911983

PSA-alpha-2-macroglobulin complex is enzymatically active in the serum of patients with advanced prostate cancer and can degrade circulating peptide hormones.

Science.gov (United States)

Kostova, Maya B; Brennen, William Nathaniel; Lopez, David; Anthony, Lizamma; Wang, Hao; Platz, Elizabeth; Denmeade, Samuel R

2018-08-01

Prostate cancer cells produce high levels of the serine protease Prostate-Specific Antigen (PSA). PSA is enzymatically active in the tumor microenvironment but is presumed to be enzymatically inactive in the blood due to complex formation with serum protease inhibitors α-1-antichymotrypsin and α-2-macroglobulin (A2M). PSA-A2M complexes cannot be measured by standard ELISA assays and are also rapidly cleared from the circulation. Thus the exact magnitude of PSA production by prostate cancer cells is not easily measured. The PSA complexed to A2M is unable to cleave proteins but maintains the ability to cleave small peptide substrates. Thus, in advanced prostate cancer, sufficient PSA-A2M may be in circulation to effect total A2M levels, levels of cytokines bound to A2M and hydrolyze small circulating peptide hormones. Total A2M levels in men with advanced prostate cancer and PSA levels above 1000 ng/mL were measured by ELISA and compared to controls. Additional ELISA assays were used to measure levels of IL-6 and TGF-beta which can bind to A2M. The ability of PSA-A2M complexes to hydrolyze protein and peptide substrates was analyzed ± PSA inhibitor. Enzymatic activity of PSA-A2M in serum of men with high PSA levels was also assayed. Serum A2M levels are inversely correlated with PSA levels in men with advanced prostate cancer. Il-6 Levels are significantly elevated in men with PSA >1000 ng/mL compared to controls with PSA PSA-A2M complex in serum of men with PSA levels >1000 ng/mL can hydrolyze small fluorescently labeled peptide substrates but not large proteins that are PSA substrates. PSA can hydrolyze small peptide hormones like PTHrP and osteocalcin. PSA complexed to A2M retains the ability to degrade PTHrP. In advanced prostate cancer with PSA levels >1000 ng/mL, sufficient PSA-A2M is present in circulation to produce enzymatic activity against circulating small peptide hormones. Sufficient PSA is produced in advanced prostate cancer to alter

Impact of total PSA, PSA doubling time and PSA velocity on detection rates of 11C-Choline positron emission tomography in recurrent prostate cancer

NARCIS (Netherlands)

Rybalov, Maxim; Breeuwsma, Anthonius J.; Leliveld, Anna M.; Pruim, Jan; Dierckx, Rudi A.; de Jong, Igle J.

PURPOSE: To evaluate the effect of total PSA (tPSA) and PSA kinetics on the detection rates of (11)C-Choline PET in patients with biochemical recurrence (BCR) after radical prostatectomy (RP) or external beam radiotherapy (EBRT). METHODS: We included 185 patients with BCR after RP (PSA >0.2 ng/ml)

The use of living PSA in safety management, a procedure developed in the nordic project ''safety evaluation, NKS/SIK-1''

International Nuclear Information System (INIS)

Johanson, G.; Holmberg, J.

1994-01-01

The essential objective with the development of a living PSA concept is to bring the use of the plant specific PSA model out to the daily safety work to allow operational risk experience feedback and to increase the risk awareness of the intended users. This paper will present results of the Nordic project ''Safety Evaluation, NKS/SIK-1''. The SIK-1 project has defined and demonstrated the practical use of living PSA for safety evaluation and for identification of possible improvements in operational safety. Subjects discussed in this paper are dealing with the practical implementation and use of PSA to make proper safety related decisions and evaluation. (author). 24 refs, 1 fig., 1 tab

Radiographic progression with nonrising PSA in metastatic castration-resistant prostate cancer

DEFF Research Database (Denmark)

Bryce, A H; Alumkal, J J; Armstrong, A

2017-01-01

monitoring alone to determine disease status on therapy. This approach has not been adequately tested. METHODS: Chemotherapy-naive asymptomatic or mildly symptomatic men (n=872) with metastatic castration-resistant prostate cancer (mCRPC) who were treated with the androgen receptor inhibitor enzalutamide......BACKGROUND: Advanced prostate cancer is a phenotypically diverse disease that evolves through multiple clinical courses. PSA level is the most widely used parameter for disease monitoring, but it has well-recognized limitations. Unlike in clinical trials, in practice, clinicians may rely on PSA...... treated with enzalutamide. As restaging in advanced prostate cancer patients is often guided by increases in PSA levels, our results demonstrate that disease progression on enzalutamide can occur without rising PSA levels. Therefore, a disease monitoring strategy that includes imaging not entirely reliant...

NPP Krsko Living PSA Concept

International Nuclear Information System (INIS)

Vrbanic, I.; Spiler, J.

2000-01-01

NPP Krsko developed PSA model of internal and external initiators within the frame of the Individual Plant Examination (IPE) project. Within this project PSA model was used to examine the existing plant design features. In order to continue with use of this PSA model upon the completion of IPE in various risk-informed applications in support of plant operation and evaluations of design changes, an appropriate living PSA concept needed to be defined. The Living PSA concept is in NPP Krsko considered as being a set of activities pursued in order to update existing PSA model in a manner that it appropriately represents the plant design, operation practice and history. Only a PSA model which is being updated in this manner can serve as a platform for plant-specific risk informed applications. The NPP Krsko living PSA concept is based on the following major ponts. First, the baseline PSA model is defined, which is to be maintained and updated and which is to be reference point for any risk-informed application. Second, issues having a potential for impact on baseline PSA model are identified and procedure and responsibilities for their permanent monitoring and evaluation are established. Third, manner is defined in which consequential changes to baseline PSA model are implemented and controlled, together with associated responsibilities. Finally, the process is defined by which the existing version of baseline PSA model is superseded by a new one. Each time a new version of baseline PSA model is released, it would be re-quantified and the results evaluated and interpreted. By documenting these re-quantifications and evaluations of results in a sequence, the track is being kept of changes in long-term averaged risk perspective, represented by long-term averaged frequencies of core damage and pre-defined release categories. These major topics of NPP Krsko living PSA concept are presented and discussed in the paper. (author)

Workshop on PSA applications, Sofia, Bulgaria, 7-11 October 1996. Lecturing materials

International Nuclear Information System (INIS)

1997-01-01

The objective of this workshop was to present detailed, systematic and useful information about PSA-based tools and PSA applications. The first presentation of the workshop was titled ''The role of PSA in safety management''. This topic served to introduce the workshop and to highlight several concepts that were afterwards stressed during the week, i.e. the defence in depth principle and the use of deterministic and probabilistic approaches in a complementary way. This presentation provided a basis for the discussion of ''PSA applications''. As a complement to the theoretical lectures, there was a workshop during which three different exercises were run in parallel. For two of these, computer-based PSA tools were used. One of them was focused towards the analysis of design modifications and the other one towards demonstrating configuration control strategies. The objective of the third practice was to obtain Allowed Outage Times using different PSA-based approaches and to discuss the differences observed and the insights obtained. To conclude the workshop, stress was put on the importance of the quality of the PSA (the development of a high quality Living PSA should be the first step), the necessity to be cautious (before taking decisions both the qualitative and numerical results should be carefully analyzed), and the logical order for the implementation of PSA applications. Refs, figs, tabs

Procedure for conducting probabilistic safety assessment: level 1 full power internal event analysis

Energy Technology Data Exchange (ETDEWEB)

Jung, Won Dae; Lee, Y. H.; Hwang, M. J. [and others

2003-07-01

This report provides guidance on conducting a Level I PSA for internal events in NPPs, which is based on the method and procedure that was used in the PSA for the design of Korea Standard Nuclear Plants (KSNPs). Level I PSA is to delineate the accident sequences leading to core damage and to estimate their frequencies. It has been directly used for assessing and modifying the system safety and reliability as a key and base part of PSA. Also, Level I PSA provides insights into design weakness and into ways of preventing core damage, which in most cases is the precursor to accidents leading to major accidents. So Level I PSA has been used as the essential technical bases for risk-informed application in NPPs. The report consists six major procedural steps for Level I PSA; familiarization of plant, initiating event analysis, event tree analysis, system fault tree analysis, reliability data analysis, and accident sequence quantification. The report is intended to assist technical persons performing Level I PSA for NPPs. A particular aim is to promote a standardized framework, terminology and form of documentation for PSAs. On the other hand, this report would be useful for the managers or regulatory persons related to risk-informed regulation, and also for conducting PSA for other industries.

Prostate-specific antigen (PSA) density in the diagnostic algorithm of prostate cancer.

Science.gov (United States)

Nordström, Tobias; Akre, Olof; Aly, Markus; Grönberg, Henrik; Eklund, Martin

2018-04-01

Screening for prostate cancer using prostate-specific antigen (PSA) alone leads to un-necessary biopsying and overdiagnosis. PSA density is easily accessible, but early evidence on its use for biopsy decisions was conflicting and use of PSA density is not commonly recommended in guidelines. We analyzed biopsy outcomes in 5291 men in the population-based STHLM3 study with PSA ≥ 3 ng/ml and ultrasound-guided prostate volume measurements by using percentages and regression models. PSA density was calculated as total PSA (ng/ml) divided by prostate volume (ml). Main endpoint was clinically significant cancer (csPCa) defined as Gleason Score ≥ 7. The median PSA-density was 0.10 ng/ml 2 (IQR 0.075-0.14). PSA-density was associated with the risk of finding csPCa both with and without adjusting for the additional clinical information age, family history, previous biopsies, total PSA and free/total PSA (OR 1.06; 95% CI:1.05-1.07 and OR 1.07, 95% CI 1.06-1.08). Discrimination for csPCa was better when PSA density was added to a model with additional clinical information (AUC 0.75 vs. 0.73, P PSA-density. Omitting prostate biopsy for men with PSA-density ≤0.07 ng/ml 2 would save 19.7% of biopsy procedures, while missing 6.9% of csPCa. PSA-density cutoffs of 0.10 ng/ml 2 and 0.15 ng/ml 2 resulted in detection of 77% (729/947) and 49% (461/947) of Gleason Score ≥7 tumors. PSA-density might inform biopsy decisions, and spare some men from the morbidity associated with a prostate biopsy and diagnosis of low-grade prostate cancer.

Development of PSA workstation KIRAP

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae Un; Han, Sang Hoon; Kim, Kil You; Yang, Jun Eon; Jeong, Won Dae; Chang, Seung Cheol; Sung, Tae Yong; Kang, Dae Il; Park, Jin Hee; Lee, Yoon Hwan; Hwang, Mi Jeong

1997-01-01

Advanced Research Group of Korea Atomic Energy Research Institute has been developing the Probabilistic Safety Assessment(PSA) workstation KIRAP from 1992. This report describes the recent development activities of PSA workstation KIRAP. The first is to develop and improve the methodologies for PSA quantification, that are the incorporation of fault tree modularization technique, the improvement of cut set generation method, the development of rule-based recovery, the development of methodology to solve a fault tree which has the logical loops and to handle a fault tree which has several initiators. These methodologies are incorporated in the PSA quantification software KIRAP-CUT. The second is to convert PSA modeling softwares for Windows, which have been used on the DOS environment since 1987. The developed softwares are the fault tree editor KWTREE, the event tree editor CONPAS, and Data manager KWDBMAN for event data and common cause failure (CCF) data. With the development of PSA workstation, it makes PSA modeling and PSA quantification and automation easier and faster. (author). 8 refs.

Development of PSA workstation KIRAP

International Nuclear Information System (INIS)

Kim, Tae Un; Han, Sang Hoon; Kim, Kil You; Yang, Jun Eon; Jeong, Won Dae; Chang, Seung Cheol; Sung, Tae Yong; Kang, Dae Il; Park, Jin Hee; Lee, Yoon Hwan; Hwang, Mi Jeong.

1997-01-01

Advanced Research Group of Korea Atomic Energy Research Institute has been developing the Probabilistic Safety Assessment(PSA) workstation KIRAP from 1992. This report describes the recent development activities of PSA workstation KIRAP. The first is to develop and improve the methodologies for PSA quantification, that are the incorporation of fault tree modularization technique, the improvement of cut set generation method, the development of rule-based recovery, the development of methodology to solve a fault tree which has the logical loops and to handle a fault tree which has several initiators. These methodologies are incorporated in the PSA quantification software KIRAP-CUT. The second is to convert PSA modeling softwares for Windows, which have been used on the DOS environment since 1987. The developed softwares are the fault tree editor KWTREE, the event tree editor CONPAS, and Data manager KWDBMAN for event data and common cause failure (CCF) data. With the development of PSA workstation, it makes PSA modeling and PSA quantification and automation easier and faster. (author). 8 refs

Generation of monoclonal antibodies against prostate specific antigen (PSA) for the detection of PSA and its purification; Generación de anticuerpos monoclonales contra el antígeno específico de próstata (PSA) para la detección del PSA y su purificación

Energy Technology Data Exchange (ETDEWEB)

Acevedo Castro, Boris Ernesto [Centro de Ingeniería Genética y Biotecnología, CIGB, La Habana (Cuba)

2012-07-01

The prostate cancer in Cuba is a problem of health (2672 diagnosed cases and 2769 deaths in 2007). Various diagnostic methods have been implemented for the detection and management of this disease, emphasizing among them (PSA) prostate-specific antigen serological determination. At this work was generated and characterized a panel of 11 antibodies (AcMs) monoclonal IgG1 detected with high affinity described major epitopes of the PSA, both in solution and attached to the test plate. From the panel obtained AcMs was the standardization of an essay type ELISA for the detection of serum total PSA (associated and free) equimolar, based on antibody monoclonal CB-PSA.4 in the coating and the CB-PSA.9 coupled with biotin as liner, with a detection limit of 0.15 ng/mL. Similarly, standardized system for detection in serum free PSA, based on the AcMs CB-PSA.4 (coating) and CB-PSA.2 coupled with biotin (liner), with a detection limit of 0.5 ng/mL. Finally, with the purpose of using PSA as standard in trials type ELISA, developed a simple method of inmunopurificación based on the AcM, CB-PSA.2, which was obtained the PSA with a purity exceeding 90%. Immunoassay Centre on the basis of the AcMs panel and the results of this study, developed and recorded two diagnostic systems for the detection of PSA in human serum. (author)

Increasing Fractional Doses Increases the Probability of Benign PSA Bounce in Patients Undergoing Definitive HDR Brachytherapy for Prostate Cancer

Energy Technology Data Exchange (ETDEWEB)

Hauck, Carlin R.; Ye, Hong; Chen, Peter Y.; Gustafson, Gary S.; Limbacher, Amy; Krauss, Daniel J., E-mail: Daniel.krauss@beaumont.edu

2017-05-01

Purpose: Prostate-specific antigen (PSA) bounce is a temporary elevation of the PSA level above a prior nadir. The purpose of this study was to determine whether the frequency of a PSA bounce following high-dose-rate (HDR) interstitial brachytherapy for the treatment of prostate cancer is associated with individual treatment fraction size. Methods and Materials: Between 1999 and 2014, 554 patients underwent treatment of low- or intermediate-risk prostate cancer with definitive HDR brachytherapy as monotherapy and had ≥3 subsequent PSA measurements. Four different fraction sizes were used: 950 cGy × 4 fractions, 1200 cGy × 2 fractions, 1350 cGy × 2 fractions, 1900 cGy × 1 fraction. Four definitions of PSA bounce were applied: ≥0.2, ≥0.5, ≥1.0, and ≥2.0 ng/mL above the prior nadir with a subsequent return to the nadir. Results: The median follow-up period was 3.7 years. The actuarial 3-year rate of PSA bounce for the entire cohort was 41.3%, 28.4%, 17.4%, and 6.8% for nadir +0.2, +0.5, +1.0, and +2.0 ng/mL, respectively. The 3-year rate of PSA bounce >0.2 ng/mL was 42.2%, 32.1%, 41.0%, and 59.1% for the 950-, 1200-, 1350-, and 1900-cGy/fraction levels, respectively (P=.002). The hazard ratio for bounce >0.2 ng/mL for patients receiving a single fraction of 1900 cGy compared with those receiving treatment in multiple fractions was 1.786 (P=.024). For patients treated with a single 1900-cGy fraction, the 1-, 2-, and 3-year rates of PSA bounce exceeding the Phoenix biochemical failure definition (nadir +2 ng/mL) were 4.5%, 18.7%, and 18.7%, respectively, higher than the rates for all other administered dose levels (P=.025). Conclusions: The incidence of PSA bounce increases with single-fraction HDR treatment. Knowledge of posttreatment PSA kinetics may aid in decision making regarding management of potential biochemical failures.

Increasing Fractional Doses Increases the Probability of Benign PSA Bounce in Patients Undergoing Definitive HDR Brachytherapy for Prostate Cancer

International Nuclear Information System (INIS)

Hauck, Carlin R.; Ye, Hong; Chen, Peter Y.; Gustafson, Gary S.; Limbacher, Amy; Krauss, Daniel J.

2017-01-01

Purpose: Prostate-specific antigen (PSA) bounce is a temporary elevation of the PSA level above a prior nadir. The purpose of this study was to determine whether the frequency of a PSA bounce following high-dose-rate (HDR) interstitial brachytherapy for the treatment of prostate cancer is associated with individual treatment fraction size. Methods and Materials: Between 1999 and 2014, 554 patients underwent treatment of low- or intermediate-risk prostate cancer with definitive HDR brachytherapy as monotherapy and had ≥3 subsequent PSA measurements. Four different fraction sizes were used: 950 cGy × 4 fractions, 1200 cGy × 2 fractions, 1350 cGy × 2 fractions, 1900 cGy × 1 fraction. Four definitions of PSA bounce were applied: ≥0.2, ≥0.5, ≥1.0, and ≥2.0 ng/mL above the prior nadir with a subsequent return to the nadir. Results: The median follow-up period was 3.7 years. The actuarial 3-year rate of PSA bounce for the entire cohort was 41.3%, 28.4%, 17.4%, and 6.8% for nadir +0.2, +0.5, +1.0, and +2.0 ng/mL, respectively. The 3-year rate of PSA bounce >0.2 ng/mL was 42.2%, 32.1%, 41.0%, and 59.1% for the 950-, 1200-, 1350-, and 1900-cGy/fraction levels, respectively (P=.002). The hazard ratio for bounce >0.2 ng/mL for patients receiving a single fraction of 1900 cGy compared with those receiving treatment in multiple fractions was 1.786 (P=.024). For patients treated with a single 1900-cGy fraction, the 1-, 2-, and 3-year rates of PSA bounce exceeding the Phoenix biochemical failure definition (nadir +2 ng/mL) were 4.5%, 18.7%, and 18.7%, respectively, higher than the rates for all other administered dose levels (P=.025). Conclusions: The incidence of PSA bounce increases with single-fraction HDR treatment. Knowledge of posttreatment PSA kinetics may aid in decision making regarding management of potential biochemical failures.

Hand Hygiene in Healthcare Settings 1 PSA (:30)

Centers for Disease Control (CDC) Podcasts

This 30 second PSA encourages people to wash their hands often while in the hospital or visiting someone in the hospital. It also encourages them to remind their healthcare providers to wash their hands, too.

The relation of serum PSA and Gleason's grade in patients with prostacic carcinoma

Directory of Open Access Journals (Sweden)

Živković Slađana

2003-01-01

Full Text Available The prostatic adenocarcinoma is one of the most frequent malignant tumors of men over 50 years of age. It is distinguished by agressive clinical course and heterogeneous multifocal hystomorphologic changes. PSA is the most reliable serum marker in diagnostics and observation of prostatic carcinoma and gleason's system of tumor-diferentiation grading is generally accepted way of determining the hystologic grade. Gleason's system is correlated with serum levels of PSA and with biological behaviour of the tumor. We presented 40 patients with verified ACP in whom the level of serum PSA, gleason's grade and score were compared. Highly significant correlation was found between serum level of PSA and the differentation grade of the tumor - Gleason's grade and score. Combination of PSA parameters and Gleason's score enables correct estimation of tumor's behaviour and correct therapeutic protocole.

IAEA work with guides for PSA quality

International Nuclear Information System (INIS)

Hellstroem, Per

2004-09-01

IAEA has a project on development of a TECDOC 'PSA Quality for Various Applications'. The project develops the guidance document in stages with intermediate meetings with exchange of ideas, thoughts and experience. Draft versions are being produced successively. The objective with the project is to use attributes to describe the quality of different elements of a PSA (Analysis of initiating events, accident progression, system, data, human reliability, etc) making the PSA suitable for application in various risk informed activities. Two of the meetings in this project took place in February 2004 and in July 2004. The February meeting discussed different aspects of PSA quality in relation to applications and a draft of the TECDOC was reviewed. The meeting made recommendations for preparation of a final document and set priorities for further work in the area. The July meeting elaborated the document further in a small working group and a new draft version was prepared. A final version is expected to be published during 2005. The project has come to the conclusion that it is a limited number of PSA element attributes that are specific for a certain application. Most of the attributes concern plant specificity, realism and level of detail in a general manner, how plant specific is the model, how realistic and how detailed? Many attributes have the characteristic that they are good to have, but not necessarily needed to do the job. This last statement is valid both for a baseline PSA and a PSA application. The IAEA project has identified a limited number of attributes that are necessary to describe characteristics needed for specific applications. The PSA scope needed for a specific application is not covered by the project/document, even though it is obvious that different applications will need different scope or approaches to handle scope limitations. The guidance on performing a PSA available today is old. It is a need to review these guides and update with regard

Optimal screening interval for men with low baseline prostate-specific antigen levels (≤1.0 ng/mL) in a prostate cancer screening program.

Science.gov (United States)

Urata, Satoko; Kitagawa, Yasuhide; Matsuyama, Satoko; Naito, Renato; Yasuda, Kenji; Mizokami, Atsushi; Namiki, Mikio

2017-04-01

To optimize the rescreening schedule for men with low baseline prostate-specific antigen (PSA) levels, we evaluated men with baseline PSA levels of ≤1.0 ng/mL in PSA-based population screening. We enrolled 8086 men aged 55-69 years with baseline PSA levels of ≤1.0 ng/mL, who were screened annually. The relationships of baseline PSA and age with the cumulative risks and clinicopathological features of screening-detected cancer were investigated. Among the 8086 participants, 28 (0.35 %) and 18 (0.22 %) were diagnosed with prostate cancer and cancer with a Gleason score (GS) of ≥7 during the observation period, respectively. The cumulative probabilities of prostate cancer at 12 years were 0.42, 1.0, 3.4, and 4.3 % in men with baseline PSA levels of 0.0-0.4, 0.5-0.6, 0.7-0.8, and 0.9-1.0 ng/mL, respectively. Those with GS of ≥7 had cumulative probabilities of 0.42, 0.73, 2.8, and 1.9 %, respectively. The cumulative probabilities of prostate cancer were significantly lower when baseline PSA levels were 0.0-0.6 ng/mL compared with 0.7-1.0 ng/mL. Prostate cancer with a GS of ≥7 was not detected during the first 10 years of screening when baseline PSA levels were 0.0-0.6 ng/mL and was not detected during the first 2 years when baseline PSA levels were 0.7-1.0 ng/mL. Our study demonstrated that men with baseline PSA levels of 0.0-0.6 ng/mL might benefit from longer screening intervals than those recommended in the guidelines of the Japanese Urological Association. Further investigation is needed to confirm the optimal screening interval for men with low baseline PSA levels.

Rate of PSA rise predicts metastatic versus local recurrence after definitive radiotherapy

International Nuclear Information System (INIS)

Sartor, C.I.; Strawderman, M.H.; Lin, X.; Kish, K.E.; McLaughlin, P.W.; Lichter, A.S.; Sandler, H.S.

1995-01-01

Objective: A rising PSA following treatment for adenocarcinoma of the prostate indicates eventual clinical failure, but the rate of rise can be quite different from patient to patient, as can the pattern of clinical failure. We sought to determine whether the rate of PSA rise could differentiate future local vs. metastatic failure. Materials and Methods: PSA values from our series of 671 patients treated between 1987 and 1994 with 3-D conformal radiotherapy for localized adenocarcinoma were analyzed. Patients who had a pre-treatment PSA and >4 post-treatment PSA values available, had received no hormonal therapy, and had information detailing clinical outcome were used in this analysis. First site of failure was determined by abnormal DRE or biopsy, abnormal bone scan or radiographic evidence of metastasis as directed by clinical symptoms or follow-up clinical exam. Each patient's PSA pattern was defined by the function PSA(t)=C 1 e - a 1 (t) + C 2 e a 2 (t) where -a 1 relates to the rate of decline and a 2 to the rate of rise, if any. Univariate analysis was used to determine the correlation between initial PSA or rising PSA and clinical failure. Adjacent category logistic regression analysis was used to analyze the rate of rise and pattern of clinical failure. Results: 671 patients were reviewed; 401 patients met the requirements and 2667 PSA values were analyzed. We confirmed the finding of others that pre-treatment PSA is a prognostic indicator: patients presenting with PSA 3-20ng/ml had a relative risk of 9 (p=0.03) and PSA>20ng/ml had a RR of 26 (p=0.002) for clinical failure when compared to presenting PSA 2 >1.5/year predicted metastatic as opposed to local failure when compared to PSA rise with a 2 between 0.5-1.5/yr or 1.5 log(ng/ml)/year vs. 0.5-1.5 log(ng/ml)/yr or <0.5 log(ng/ml)/yr. Conclusions: The rate of rise of PSA following definitive radiotherapy can predict clinical failure patterns, with a rapidly rising PSA indicating metastatic as opposed to

Pattern of Prostate-Specific Antigen (PSA) Failure Dictates the Probability of a Positive Bone Scan in Patients With an Increasing PSA After Radical Prostatectomy

Science.gov (United States)

Dotan, Zohar A.; Bianco, Fernando J.; Rabbani, Farhang; Eastham, James A.; Fearn, Paul; Scher, Howard I.; Kelly, Kevin W.; Chen, Hui-Ni; Schöder, Heiko; Hricak, Hedvig; Scardino, Peter T.; Kattan, Michael W.

2007-01-01

Purpose Physicians often order periodic bone scans (BS) to check for metastases in patients with an increasing prostate-specific antigen (PSA; biochemical recurrence [BCR]) after radical prostatectomy (RP), but most scans are negative. We studied patient characteristics to build a predictive model for a positive scan. Patients and Methods From our prostate cancer database we identified all patients with detectable PSA after RP. We analyzed the following features at the time of each bone scan for association with a positive BS: preoperative PSA, time to BCR, pathologic findings of the RP, PSA before the BS (trigger PSA), PSA kinetics (PSA doubling time, PSA slope, and PSA velocity), and time from BCR to BS. The results were incorporated into a predictive model. Results There were 414 BS performed in 239 patients with BCR and no history of androgen deprivation therapy. Only 60 (14.5%) were positive for metastases. In univariate analysis, preoperative PSA (P = .04), seminal vesicle invasion (P = .02), PSA velocity (P < .001), and trigger PSA (P < .001) predicted a positive BS. In multivariate analysis, only PSA slope (odds ratio [OR], 2.71; P = .03), PSA velocity (OR, 0.93; P = .003), and trigger PSA (OR, 1.022; P < .001) predicted a positive BS. A nomogram for predicting the bone scan result was constructed with an overfit-corrected concordance index of 0.93. Conclusion Trigger PSA, PSA velocity, and slope were associated with a positive BS. A highly discriminating nomogram can be used to select patients according to their risk for a positive scan. Omitting scans in low-risk patients could reduce substantially the number of scans ordered. PMID:15774789

Risk evaluations of aging: Procedures guide for an age-dependent PSA with emphasis on prioritization and sensitivity studies

International Nuclear Information System (INIS)

Vesely, W.E.

1991-01-01

Based on the previous work which has been performed in the project, a procedures guide is being developed for carrying out an age-dependent probabilistic safety assessment (PSA) for evaluating the core damage frequency with aging effects explicitly treated. A PSA is basically a Level 1 Probabilistic Risk Assessment (PRA). The emphasis of the guide is on prioritization and sensitivity studies. Focus is also on active components although consideration of aging effects in passive components is also treated. The guide is intended to become a NUREG/CR and is the first of three volumes which are being developed. The following topics with demonstrations and applications are described in the presentation: (1) the age-dependent PSA versus the standard PSA; (2) component reliability models used in an age-dependent PSA; (3) approaches for transforming a PSA into an age-dependent PSA; (4) application of an age-dependent PSA; (5) using a PSA to evaluate the risk effects from aging passive components; (6) evaluation of the risk importance of passive components; (7) prioritizations of aging contributors; (8) evaluations of test and maintenance effectiveness; and (9) sensitivity studies and uncertainty analyses of aging effects

Possible factors influencing high serum Prostate-specific Antigen (PSA in Indonesian patients with Benign Prostatic Hyperplasia (BPH

Directory of Open Access Journals (Sweden)

Djoko Rahardjo

2001-03-01

Full Text Available Benign prostatic hyperplasia (BPH cases in Indonesia frequently associated with high serum prostate specific antigen (PSA. To explore possible factors that could increase serum PSA level, we performed a retrospective, cross-sectional study on 805 consecutive patients in Sumber Waras and Dr. Cipto Mangunkusumo Hospitals from 1994 to 1997. Clinical manifestations were evaluated and prostate biopsies were performed if indicated. Complete histopathological data were only available in 82 BPH patients with no urinary retention from 1998-1999 and a thin section of paraffin blocks of BPH patients which still could be found from 1994-1999 was analyzed using flow cytometer to obtain the S-phase fraction as a parameter of proliferative activity, From 805 patients, 461 (57% presented with urinary retention and need to be catheteized. Catheteization significantly increased PSA level if compared to noncatheterized patients (16.3 vs. 6,8 ng/mL, p= 0,000. Another data of 82 uncatheteized patients from 1998-1999 has revealed that 79 patients (96.3% had chronic prostatitis and 19 (23.2% showed the presence of prostatic-intraepithelial neoplasia (PIN with an increase of PSA level (5.4 ng/mL. The S-phase fraction of BPH without PIN cases was significantly higher in cases with PSA > 4 ng/ml than patients with PSA ≤ 4 ng/ml (I3.1% vs. 8.9%, p=0,008. As conclusion, the high serum PSA level was mostly due to urethral catheteization and increased prostate volume. There was a tendency of increasing PSA in subclinical inflammation and PIN. Cases with high PSA also showed high proliferative activities which is suggestive of mitogenic activity. (Med J Indones 2001; 10:22-8Keywords: BPH, high PSA, PIN, proliferative activity, s-phase fraction

Prostate-Specific Antigen (PSA) Test

Science.gov (United States)

... Cancer Prostate Cancer Screening Research Prostate-Specific Antigen (PSA) Test On This Page What is the PSA ... parts of the body before being detected. The PSA test may give false-positive or false-negative ...

Qualification of calculation aids for PSA

International Nuclear Information System (INIS)

Goetz, K.; Hennigs, W.; Kirstein, B.M.; Reinhardt, C.

1998-01-01

In Germany Probabilistic Safety Analysis (PSA) are part of the evaluation of a nuclear power plants safety. The German PSA guide stipulates that the used software must enable a PSA according to the state of the art. This software must be qualified to assure that its features, mathematic methods and its performance enable a PSA like this. In this research work specifications and requirements are developed, which allow the testing of software. A procedure was developed to qualify PSA software according to the PSA guide and the experiences of users of PSA. Setting up a procedure, a tool for a systematic and uniform examination was crated. Additionally the options, mathematic fundamentals and performance of PSA-programs were analyzed. According to this all programs that were analyzed are capable to sovle their original task, that is the calculation of the safety of high available system based on high available components. Against that the requirements of modern PSA, e.g. to handle less available functions, HRA and fire analyses, based on the use of modern software and the implementation of new developments in the field of PSA are not supported adequately by all programs. (orig.) [de

Clinical performance of serum prostate-specific antigen isoform [-2]proPSA (p2PSA) and its derivatives, %p2PSA and the prostate health index (PHI), in men with a family history of prostate cancer: results from a multicentre European study, the PROMEtheuS project.

Science.gov (United States)

Lazzeri, Massimo; Haese, Alexander; Abrate, Alberto; de la Taille, Alexandre; Redorta, Joan Palou; McNicholas, Thomas; Lughezzani, Giovanni; Lista, Giuliana; Larcher, Alessandro; Bini, Vittorio; Cestari, Andrea; Buffi, Nicolòmaria; Graefen, Markus; Bosset, Olivier; Le Corvoisier, Philippe; Breda, Alberto; de la Torre, Pablo; Fowler, Linda; Roux, Jacques; Guazzoni, Giorgio

2013-08-01

To test the sensitivity, specificity and accuracy of serum prostate-specific antigen isoform [-2]proPSA (p2PSA), %p2PSA and the prostate health index (PHI), in men with a family history of prostate cancer (PCa) undergoing prostate biopsy for suspected PCa. To evaluate the potential reduction in unnecessary biopsies and the characteristics of potentially missed cases of PCa that would result from using serum p2PSA, %p2PSA and PHI. The analysis consisted of a nested case-control study from the PRO-PSA Multicentric European Study, the PROMEtheuS project. All patients had a first-degree relative (father, brother, son) with PCa. Multivariable logistic regression models were complemented by predictive accuracy analysis and decision-curve analysis. Of the 1026 patients included in the PROMEtheuS cohort, 158 (15.4%) had a first-degree relative with PCa. p2PSA, %p2PSA and PHI values were significantly higher (P PHI (AUC: 0.733) to be the most accurate predictors of PCa at biopsy, significantly outperforming total PSA ([tPSA] AUC: 0.549), free PSA ([fPSA] AUC: 0.489) and %fPSA (AUC: 0.600) (P ≤ 0.001). For %p2PSA a threshold of 1.66 was found to have the best balance between sensitivity and specificity (70.4 and 70.1%; 95% confidence interval [CI]: 58.4-80.7 and 59.4-79.5 respectively). A PHI threshold of 40 was found to have the best balance between sensitivity and specificity (64.8 and 71.3%, respectively; 95% CI 52.5-75.8 and 60.6-80.5). At 90% sensitivity, the thresholds for %p2PSA and PHI were 1.20 and 25.5, with a specificity of 37.9 and 25.5%, respectively. At a %p2PSA threshold of 1.20, a total of 39 (24.8%) biopsies could have been avoided, but two cancers with a Gleason score (GS) of 7 would have been missed. At a PHI threshold of 25.5 a total of 27 (17.2%) biopsies could have been avoided and two (3.8%) cancers with a GS of 7 would have been missed. In multivariable logistic regression models, %p2PSA and PHI achieved independent predictor status and

Conformal technique dose escalation in prostate cancer: improved cancer control with higher doses in patients with pretreatment PSA {>=} 10 ngm/ml

Energy Technology Data Exchange (ETDEWEB)

Hanks, G E; Lee, W R; Hanlon, A L; Kaplan, E; Epstein, B; Schultheiss, T

1995-07-01

Purpose: Single institutions and an NCI supported group of institutions have been investigating the value of dose escalation in patients with prostate cancer treated by conformal treatment techniques. Improvement in morbidity has been previously established, while this report identifies the pretreatment PSA level subgroups of patients who benefitted in cancer control from higher dose. Materials and Methods: We report actuarial bNED survival rates for 375 consecutive patients with known pretreatment PSA levels treated with conformal technique between 5/89 and 12/93. The whole pelvis was treated to 45 Gy in 25 fractions in all T2C,3, all Gleason 8, 9, 10 and all patients with pretreatment PSA {>=}20. The prostate {+-} seminal vesicles was boosted at 2.1 Gy/day to the center of the prostate to 65-79 Gy (65-69 N=50), 70-72.49 N=94, 72.5-74.9 N=82, 75-77.49 N=129 and {>=}77.5 N=20). The median followup is 21 mos with a range of 3 to 67 mos. The highest dose patients have the least followup, reducing the impact of the highest dose levels at this time. Patients are analyzed for the entire group divided at 71 Gy and at 73 Gy calculated at the center of the prostate. Each dose group is then subdivided by pretreatment PSA levels <10, 10-19.9, and {>=}20 ngm/ml and dose levels are compared within pretreatment PSA level group. bNED failure is defined as PSA {>=}1.5 ngm/ml and rising on two consecutive values. Results: Table 1 shows the bNED survival rates at 24 and 36 mos for all patients and the three pretreatment PSA level groups. For all patients pooled, there is an overall advantage to using doses {>=}71 Gy (64% vs 85% at 36 mo, p=.006) and {>=}73 Gy (71% vs 86% at 36 mo, p=.07). The subgroup of PSA <10 ngm/ml, however, shows no benefit in bNED survival when using doses over 71 Gy (90% vs 93% at 36 mo) or 73 Gy (91 vs 94% at 36 mo). The subgroup PSA 10 ngm/ml to 19.9 ngm/ml shows improved cancer control when using doses over 71 Gy (61% vs 88% at 36 mo, p=.03) and over 73

CONPAS 1.0 (CONtainment Performance Analysis System). User's manual

International Nuclear Information System (INIS)

Ahn, Kwang Il; Jin, Young Ho

1996-04-01

CONPAS (CONtainment Performance Analysis System) is a verified computer code package to integrate the numerical, graphical, and results-operation aspects of Level 2 probabilistic safety assessments (PSA) for nuclear power plants automatically under a PC window environment. Compared with the existing DOS-based computer codes for Level 2 PSA, the most important merit of the window-based computer code is that user can easily describe and quantify the accident progression models, and manipulate the resultant outputs in a variety of ways. As a main logic for accident progression analysis, CONPAS employs a concept of the small containment phenomenological event tree (CPET) helpful to trace out visually individual accident progressions and of the large supporting event tree (LSET) for its detailed quantification. For the integrated analysis of Level 2 PSA, the code utilizes four distinct, but closely related modules; (1) ET Editor for construction of several event tree models describing the accident progressions, (2) Computer for quantification of the constructed event trees and graphical display of the resultant outputs, (3) Text Editor for preparation of input decks for quanification and utilization of calculational results, and (4) Mechanistic Code Plotter for utilization of results obtained from severe accident analysis codes. Compared with other existing computer codes for Level 2 PSA, the CONPAS code provides several advanced features: computational aspects including systematic uncertainty analysis, importance analysis, sensitivity analysis and data interpretation, reporting aspects including tabling and graphic as well as user-friend interface. 10 refs. (Author) .new

Issues reporting PSA in prostate cancer

International Nuclear Information System (INIS)

Lange, Paul H.

1996-01-01

The National Cancer Institute Prostate; Lung; Colon; Ovarian Cancer Screening (PLCO) project is a multi-center trial developed to investigate the effectiveness of DRE and PSA testing in the early detection and outcome of patients with prostate cancer. Accordingly, the Prostate Cancer Intervention versus Observation Trial (PIVOT) has been launched and is a randomized trial comparing radical prostatectomy versus expectant management for ALCaP. PSA: Initially PSA was thought to be of little value for diagnosis because 20% of men undergoing radical prostatectomy have 'normal' PSA and patients with apparently only symptomatic BPH have 'elevated' levels as follows: 4-10 ng/ml (Tandem-R) - 20%, >10 ng/ml -3%. Yet, PSA has looked attractive as a diagnostic tool in many studies; for example, when PSA was used in a screening approach as the first test which then drove further evaluation (Catalona, Brawer). It was shown that the positive predictive value for PSA's between 4 and 10 is approximately 20% and > 10 approximately 55%. The value of serial PSA's (velocity) is unknown but is under intense study: one major issue is determination of what represents a significant rise (details to be presented). Studies have also revealed that a DRE and PSA are important for optimal results. About 18% of clinically detectable cancers are only DRE positive while about 25 - 30% are only PSA positive. When both a DRE and PSA are used together, very few clinically apparent cancers are missed (3-5%). Recent ROC curves suggest that 4 ng/ml is reasonable. Recently, PSA values for men without apparent cancer were stratified by age, and taking the 2SD, age specific reference values were generated as follows: age 40-49 (0-2.5 ng/ml), 50-59 (0-3.5), 60-69 (0-4.5), 70-70 (0-6.5). Finally, there is the issue about different PSA assays regarding the compatabilities/reliability of the upper limit of normal and serial values. Much of the confusion is because there is no international PSA standard and

Review of updated design of SPWR with PSA methodology

International Nuclear Information System (INIS)

Oikawa, Tetsukuni; Muramatsu, Ken

1995-01-01

This paper presents the procedures and results of a PSA (Probabilistic Safety Assessment) of the SPWR (System-Integrated PWR), which is being developed at the Japan Atomic Energy Research Institute (JAERI) as a medium sized innovative passive safe reactor, to assist in the design improvement of the SPWR at the basic or conceptual design phase by reviewing the design and identifying the design vulnerability. The first phase PSA, which was carried out in 1991, was a scoping analysis in order to understand overall plant characteristics and to search for general design weakness. After discussing the results of the first phase PSA, the SPWR designer group changed some designs of the SPWR. The second phase PSA of the SPWR was performed for the modified design in order to identify the design vulnerability as well as to grasp its overall safety level. Special items of these PSAs are as follows: (1) systematic identification of initiating events related to newly designed systems by the failure mode effect analysis (FMEA), (2) delineation of accident sequences for the internal initiating events using accident progression flow charts which is cost effective for conceptual design phase, (3) quantification of event trees based on many engineering judgement, and (4) lots of sensitivity analyses to examine applicability of data assignment. Qualitative and quantitative results of PSA provided very useful information for decision makings of design improvement and recommendations for further consideration in the process of detailed design. (author)

Model engineering in a modular PSA

International Nuclear Information System (INIS)

Friedlhuber, Thomas

2014-01-01

For the purpose of PSA (Probabilistic Safety Analysis) for complex industrial systems, often PSA models in the form of fault and event trees are developed to model the risk of unwanted situations (hazards). While the recent decades, PSA models have gained high acceptance and have been developed massively. This lead to an increase in model sizes and complexity. Today, PSA models are often difficult to understand and maintain. This manuscript presents the concept of a modular PSA. A modular PSA tries to cope with the increased complexity by the techniques of modularization and instantiation. Modularization targets to treat a model by smaller pieces (the 'modules') to regain control over models. Instantiation aims to configure a generic model to different contexts. Both try to reduce model complexity. A modular PSA proposes new functionality to manage PSA models. Current model management is rather limited and not efficient. This manuscript shows new methods to manage the evolutions (versions) and deviations (variants) of PSA models in a modular PSA. The concepts of version and variant management are presented in this thesis. In this context, a model comparison and fusion of PSA models is precised. Model comparison provides important feedback to model engineers and model fusion kind of combines the work from different model engineers (concurrent model engineering). Apart from model management, methods to understand the content of PSA models are presented. The methods focus to highlight the dependencies between modules rather than their contents. Dependencies are automatically derived from a model structure. They express relations between model objects (for example a fault tree may have dependencies to basic events). To visualize those dependencies (for example in form of a model cartography) can constitute a crucial aid to model engineers for understanding complex interrelations in PSA models. Within the scope of this thesis, a software named 'Andromeda' has been

Relationships between serum PSA levels, Gleason scores and results of 68Ga-PSMAPET/CT in patients with recurrent prostate cancer.

Science.gov (United States)

Sanli, Yasemin; Kuyumcu, Serkan; Sanli, Oner; Buyukkaya, Fikret; İribaş, Ayça; Alcin, Goksel; Darendeliler, Emin; Ozluk, Yasemin; Yildiz, Sevda Ozel; Turkmen, Cüneyt

2017-11-01

To investigate the relationship between serum PSA level, Gleason score of PCa and the outcomes of Ga 68 -PSMA PET/CT in patients with recurrent PCa. A total of 109 consecutive patients (median age 71 years; range 48-89 years) who had PSA recurrence after RP and/or hormonotherapy and/or radiotherapy were included in this study. Local recurrences, lymph node metastasis (pelvic, abdominal and/or supradiaphragmatic), bone metastases (oligometastatic/multimetastatic) and other metastatic sites (lung, liver, brain, etc) were documented. In 91(83.4%) patients at least one lesion characteristic for PCa was detected by 68 Ga-PSMA PET/CT. The median serum total PSA (tPSA) was 6.5 (0.2-640) ng/ml.There was a significant difference between 68 Ga-PSMA PET/CT positive and negative patients in terms of serum total PSA value. No statistical significance was found between positive and negative 68 Ga-PSMA PET/CT findings in terms of Gleason score. Local recurrence was detected in 56 patients. whereas lymph node metastases were demonstrated in 46 patients. Pelvic nodal disease was the most frequent presentation followed by abdominal and supradiaphragmaticnodal involvement. Bone metastases [oligometastasis, (n = 20); multimetastasis, (n = 35)⦌ were also detected in 55 patients. In the ROC analysis for the study cohort, the optimal cut-off value of total serum PSA was determined as 0.67 ng/ml for distinguishing between positive and negative 68 Ga-PSMA PET/CT images, with an area under curve of 0.952 (95% CI 0.911-0.993). 68 Ga-PSMA PET/CT was found to be an effective tool for the detection of recurrent PCa. Even though no relationship was detected between the GS and 68 Ga-PSMA PET/CT findings, serum total PSA values may be used for estimating the likelihood of positive 68 Ga-PSMA PET/CT results.

Safety and efficacy of procedural sedation and analgesia (PSA ...

African Journals Online (AJOL)

Safety and efficacy of procedural sedation and analgesia (PSA) conducted by medical officers in a level 1 hospital in Cape Town. ... Respiratory complications were treated with simple airway manoeuvres; no patient required intubation or experienced respiratory problems after waking up. There was no significant difference ...

Relationship between PSA kinetics and [{sup 18}F]fluorocholine PET/CT detection rates of recurrence in patients with prostate cancer after total prostatectomy

Energy Technology Data Exchange (ETDEWEB)

Graute, Vera; Jansen, Nathalie; Uebleis, Christopher; Cumming, Paul; Klanke, Katharina; Tiling, Reinhold; Bartenstein, Peter; Hacker, Marcus [University of Munich, Department of Nuclear Medicine, Munich (Germany); Seitz, Michael [University of Munich, Department of Urology, Munich (Germany); Hartenbach, Markus [Bundeswehrkrankenhaus Ulm, Department of Nuclear Medicine, Ulm (Germany); Scherr, Michael Karl; Thieme, Sven [University of Munich, Institute of Clinical Radiology, Munich (Germany)

2012-02-15

The aim of the present study was to identify prostate-specific antigen (PSA) threshold levels, as well as PSA velocity, progression rate and doubling time in relation to the detectability and localization of recurrent lesions with [{sup 18}F]fluorocholine (FC) PET/CT in patients after radical prostatectomy. The study group comprised 82 consecutive patients with biochemical relapse after radical prostatectomy. PSA levels measured at the time of imaging were correlated with the FC PET/CT detection rates in the entire group with PSA velocity (in 48 patients), with PSA doubling time (in 47 patients) and with PSA progression (in 29 patients). FC PET/CT detected recurrent lesions in 51 of the 82 patients (62%). The median PSA value was significantly higher in PET-positive than in PET-negative patients (4.3 ng/ml vs. 1.0 ng/ml; p < 0.01). The optimal PSA threshold from ROC analysis for the detection of recurrent prostate cancer lesions was 1.74 ng/ml (AUC 0.818, 82% sensitivity, 74% specificity). Significant differences between PET-positive and PET-negative patients were found for median PSA velocity (6.4 vs. 1.1 ng/ml per year; p < 0.01) and PSA progression (5.0 vs. 0.3 ng/ml per year, p < 0.01) with corresponding optimal thresholds of 1.27 ng/ml per year and 1.28 ng/ml per year, respectively. The PSA doubling time suggested a threshold of 3.2 months, but this just failed to reach statistical significance (p = 0.071). In a study cohort of patients with biochemical recurrence of prostate cancer after radical prostatectomy there emerged clear PSA thresholds for the presence of FC PET/CT-detectable lesions. (orig.)

Proceedings of the 10th Korea-Japan joint workshop on PSA. For Asian PSA network

International Nuclear Information System (INIS)

Yang, Joon-Eon; Homma, Toshimitsu

2009-12-01

The tenth Korea-Japan Joint Workshop on Probabilistic Safety Assessment (PSA) was held in the Jeju island of Korea, on May 18-20, 2009 organized by Korea Atomic Energy Research Institute (KAERI). The purpose of the workshop was to provide a forum for presentation and discussions on experiences and technical achievements related to PSA, risk-informed and performance-based approach, and other relevant issues in both countries. Since the first Korea-Japan Joint Workshop on PSA started in 1992, the workshops have provided an important and timely opportunity for exchange and discussion of the relevant information to all PSA practitioners and users of risk information in the industry, research, academia and regulatory arena. This was the tenth anniversary of the Joint Workshop with the main theme of 'For Asian PSA Network' and participants included those from China, Taiwan and the United States of America besides Korea and Japan. Two keynote speeches were presented by the former chairmen of this workshop, Prof. Chang-Sun Kang of Seoul National University and Prof. emeritus Shunsuke Kondo of Tokyo University. We had two special lectures, 70 papers presented by experts at 10 technical sessions related PSA, the special session on the status of PSA in Korea, Japan, China and Taiwan and panel discussion on their cooperation in PSA. This report provides the summary of each session, and all the presentation materials presented in the 10th Korea-Japan Joint Workshop on PSA. (author)

Seismic PSA of nuclear power plants a case study

International Nuclear Information System (INIS)

Hari Prasad, M.; Dubey, P.N.; Reddy, G.R.; Saraf, R.K.; Ghosh, A.K.

2006-07-01

Seismic Probabilistic Safety Assessment (Seismic PSA) analysis is an external event PSA analysis. The objective of seismic PSA for the plants is to examine the existence of plant vulnerabilities against postulated earthquakes by numerically assessing the plant safety and to take appropriate measures to enhance the plant safety. Seismic PSA analysis integrates the seismic hazard analysis, seismic response analysis, seismic fragility analysis and system reliability/ accident sequence analysis. In general, the plant consists of normally operating and emergency standby systems and components. The failure during an earthquake (induced directly by excessive inertial stresses or indirectly following the failure of some other item) of an operating component will lead to a change in the state of the plant. In that case, various scenarios can follow depending on the initiating event and the status of other sub-systems. The analysis represents these possible chronological sequences by an event tree. The event trees and the associated fault trees model the sub-systems down to the level of individual components. The procedure has been applied for a typical Indian nuclear power plant. From the internal event PSA level I analysis significant contribution to the Core Damage Frequency (CDF) was found due to the Fire Water System. Hence, this system was selected to establish the procedure of seismic PSA. In this report the different elements that go into seismic PSA analysis have been discussed. Hazard curves have been developed for the site. Fragility curve for the seismically induced failure of Class IV power has been developed. The fragility curve for fire-water piping system has been generated. Event tree for Class IV power supply has been developed and the dominating accident sequences were identified. CDF has been estimated from these dominating accident sequences by convoluting hazard curves of initiating event and fragility curves of the safety systems. (author)

Ringhals 1 PSA - Evaluation of safety raising measures

International Nuclear Information System (INIS)

Hellstroem, P.; Enerholm, A.; Holmgren, P.

1995-09-01

A PSA-study of the BWR-reactor has been evaluated, and the following comments are made: The objectives of the study have been reached, but an overview is lacking. Means for verifying the functional demands at primary events should have a very high priority. A deeper analysis is needed to verify that overpressurizing and overfilling not cause HS. The analysis should include a report on dynamic effects at a LOCA. The level of detail in modelling functional dependencies should be increased. The low probabilities for faults caused by the operating personnel should be explained and possible defaults in instructions etc. documented. The results of the study should be analyzed deeper in comparison with other studies. Suggestions for improvement of the plant and priorities for these are missing. The documentation should be improved

Summary report of seismic PSA of BWR model plant

International Nuclear Information System (INIS)

1999-05-01

This report presents a seismic PSA (Probabilistic Safety Assessment) methodology developed at the Japan Atomic Energy Research Institute (JAERI) for evaluating risks of nuclear power plants (NPPs) and the results from an application of the methodology to a BWR plant in Japan, which is termed Model Plant'. The seismic PSA procedures developed at JAERI are to evaluate core damage frequency (CDF) and have the following four steps: (1) evaluation of seismic hazard, (2) evaluation of realistic response, (3) evaluation of component capacities and failure probabilities, and (4) evaluation of conditional probability of system failure and CDF. Although these procedures are based on the methodologies established and used in the United States, they include several unique features: (1) seismic hazard analysis is performed with use of available knowledge and database on seismological conditions in Japan; (2) response evaluation is performed with a response factor method which is cost effective and associated uncertainties can be reduced with use of modern methods of design calculations; (3) capacity evaluation is performed with use of test results available in Japan in combination with design information and generic capacity data in the U.S.A.; (4) systems reliability analysis, performed with use of the computer code SECOM-2 developed at JAERI, includes identification of dominant accident sequences, importance analysis of components and systems as well as the CDF evaluation with consideration of the effect of correlation of failures by a newly developed method based on the Monte Carlo method. The effect of correlation has been recognized as an important issue in seismic PSAs. The procedures was used to perform a seismic PSA of a 1100 MWe BWR plant. Results are shown as well as the insights derived and future research needs identified in this seismic PSA. (J.P.N.)

PROSTATE CANCER SCREENING: PSA TEST AWARENESS AMONG ADULT MALES.

Science.gov (United States)

Obana, Michael; O'Lawrence, Henry

2015-01-01

The overall purpose of this study was to determine whether visits to the doctor in the last 12 months, education level, and annual household income for adult males increased the awareness of prostate-specific antigen (PSA) tests. The effect of these factors for the knowledge of PSA exams was performed using statistical analysis. A retrospective secondary database was utilized for this study using the questionnaire in the California Health Interview Survey from 2009. Based on this survey, annual visits to the doctor, higher educational levels attained, and greater take-home pay were statistically significant and the results of the study were equivalent to those hypothesized. This also reflects the consideration of marketing PSA blood test screenings to those adult males who are poor, uneducated, and do not see the doctor on a consistent basis.

Development of a PSA information database system

International Nuclear Information System (INIS)

Kim, Seung Hwan

2005-01-01

The need to develop the PSA information database for performing a PSA has been growing rapidly. For example, performing a PSA requires a lot of data to analyze, to evaluate the risk, to trace the process of results and to verify the results. PSA information database is a system that stores all PSA related information into the database and file system with cross links to jump to the physical documents whenever they are needed. Korea Atomic Energy Research Institute is developing a PSA information database system, AIMS (Advanced Information Management System for PSA). The objective is to integrate and computerize all the distributed information of a PSA into a system and to enhance the accessibility to PSA information for all PSA related activities. This paper describes how we implemented such a database centered application in the view of two areas, database design and data (document) service

CONPAS 1.0 (CONtainment Performance Analysis System). User`s manual

Energy Technology Data Exchange (ETDEWEB)

Ahn, Kwang Il; Jin, Young Ho [Korea Atomic Energy Research Institute, Daeduk (Korea, Republic of)

1996-04-01

CONPAS (CONtainment Performance Analysis System) is a verified computer code package to integrate the numerical, graphical, and results-operation aspects of Level 2 probabilistic safety assessments (PSA) for nuclear power plants automatically under a PC window environment. Compared with the existing DOS-based computer codes for Level 2 PSA, the most important merit of the window-based computer code is that user can easily describe and quantify the accident progression models, and manipulate the resultant outputs in a variety of ways. As a main logic for accident progression analysis, CONPAS employs a concept of the small containment phenomenological event tree (CPET) helpful to trace out visually individual accident progressions and of the large supporting event tree (LSET) for its detailed quantification. For the integrated analysis of Level 2 PSA, the code utilizes four distinct, but closely related modules; (1) ET Editor for construction of several event tree models describing the accident progressions, (2) Computer for quantification of the constructed event trees and graphical display of the resultant outputs, (3) Text Editor for preparation of input decks for quanification and utilization of calculational results, and (4) Mechanistic Code Plotter for utilization of results obtained from severe accident analysis codes. Compared with other existing computer codes for Level 2 PSA, the CONPAS code provides several advanced features: computational aspects including systematic uncertainty analysis, importance analysis, sensitivity analysis and data interpretation, reporting aspects including tabling and graphic as well as user-friend interface. 10 refs. (Author) .new.

Development and application of probabilistic safety assessment PSA in Daya Bay Nuclear Power Station

International Nuclear Information System (INIS)

Huang Weigang; Chen Jiefei; Guo Jianbing; Zhen Wei

2005-01-01

This paper discusses the development and application of Level 1 PSA used for safety review, risk monitoring and on line maintenance of the nuclear power plant. PSA development includes the analysis of event tree, fault tree, FMEA, PSA quantification and the equipment reliability database. We have collected and processed the reliability data of external power source, the equipment reliability data and the initial event frequency. The thermal-hydraulics analysis of some important events and accidents, human factor analysis, and the calculation of human error probability have been made. During the development of event trees and fault trees, the effect of some support systems such as compressed air distribution system, ventilation system and electrical system have been taken into account. The system manuals, operation procedures and emergency operating procedures of Daya Bay NPP are referred to in this project. The operators of the NPP were involved in the establishment of all event trees and fault trees analysis. Furthermore, we have accepted the suggestion of IAEA experts, completed the logic chart of initial events to the initial events analysis of Daya Bay NPP, and optimized the code system of PSA model again. Together with the development of the reliability database, by absorbing the advanced experience of EDF, we have gained the reports about equipment's classifying, function and experience feedback information of Daya Bay NPP. According to the quantitative calculation of the latest Level 1 PSA Model of Daya Bay NPP, the results of Core Damage Frequency (CDF) is: CDF = 2.13E-5/reactor . year. The latest PSA Model of Daya Bay NPP includes: 1) 12 sorts of initial events, 67 sub-initial events, 70 fault trees; 2) 25 nuclear safety related systems were developed by fault trees and FMEA ; 3) 2609 fault tree logic gates; 4) 2146 basic events; 5) 680 core damage accident sequences. (authors)

Lessons of the Fukushima Dai-ichi accident for PSA

International Nuclear Information System (INIS)

Kumar, M.; Klug, J.; Alzbutas, R.; Burgazzi, L.; Farcasiu, M.; Nitoi, M.; Ivanov, I.; Bogdanov, D.; Hashimoto, K.; Hirata, K.; La Rovere, S.; Sevbo, O.; Vitazkova, J.; Hustak, S.; Wielenberg, A.; Raimond, E.

2016-01-01

The objective of this document is to identify some lessons learned from the Fukushima Dai-ichi accident for PSA. Based on the public information on the causes that have led to major radioactive release during the Fukushima Dai-ichi accident (initiating events, material and human response), the authors, ASAMPSA-E WP30 members have performed a review to examine the gaps/insufficiencies/incompleteness in the existing Level 1 and Level 2 PSAs. This is the aim of this report which is one of WP30 deliverables i.e. D30.2. The consideration of external initiating events for the different levels of defense-in-depth is one of the focal points in this review. Recommendations in the way of developing the different elements of PSAs have been proposed by the authors and were completed later during the ASAMPSA-E project. Moreover, first recommendations on the use of PSA information in decision making have been included as well. (authors)

Reviewing PSA-based analyses to modify technical specifications at nuclear power plants

International Nuclear Information System (INIS)

Samanta, P.K.; Martinez-Guridi, G.; Vesely, W.E.

1995-12-01

Changes to Technical Specifications (TSs) at nuclear power plants (NPPs) require review and approval by the United States Nuclear Regulatory Commission (USNRC). Currently, many requests for changes to TSs use analyses that are based on a plant's probabilistic safety assessment (PSA). This report presents an approach to reviewing such PSA-based submittals for changes to TSs. We discuss the basic objectives of reviewing a PSA-based submittal to modify NPP TSs; the methodology of reviewing a TS submittal, and the differing roles of a PSA review, a PSA Computer Code review, and a review of a TS submittal. To illustrate this approach, we discuss our review of changes to allowed outage time (AOT) and surveillance test interval (STI) in the TS for the South Texas Project Nuclear Generating Station. Based on this experience gained, a check-list of items is given for future reviewers; it can be used to verify that the submittal contains sufficient information, and also that the review has addressed the relevant issues. Finally, recommended steps in the review process and the expected findings of each step are discussed

Challenges and status of multi-unit PSA development in Canada

International Nuclear Information System (INIS)

Yalaoui, Smain

2015-01-01

Firstly, this paper discusses the issues and challenges related to the development of a Multi-Unit PSA (MU-PSA) and the general recommendations and conclusions from the MU-PSA Workshop organized by the CNSC in Ottawa, November 2014. This includes a discussion regarding the issue related to the methodological challenges in performing MU-PSA, the site-based risk metrics to be adopted, and the issue of risk aggregation across all hazards and all units. The paper also addresses the challenges for establishing site-based safety goals as the current safety goals were established on a per-unit basis. CNSC Staff efforts, both at the national and international level, on developing whole-site safety goals and guidance on MU-PSA and risk aggregation methodologies will also be discussed. Finally, the paper will provide a summary of the industry effort and road map for completing the pilot Whole-site PSA project for the Pickering Nuclear Generating Station, as requested by the Commission following to the public hearing for licence renewal in February 20 and May 29-31, 2013. (author)

Reactor cooling systems thermal-hydraulic assessment of the ASTEC V1.3 code in support of the French IRSN PSA-2 on the 1300 MWe PWRs

International Nuclear Information System (INIS)

Tregoures, Nicolas; Philippot, Marc; Foucher, Laurent; Guillard, Gaetan; Fleurot, Joelle

2010-01-01

The French Institut de Radioprotection et de Surete Nucleaire (IRSN) is performing a level 2 Probabilistic Safety Assessment (PSA-2) on the French 1300 MWe PWRs. This PSA-2 study is relying on the ASTEC integral computer code, jointly developed by IRSN and GRS (Germany). In order to assess the reliability and the quality of physical results of the ASTEC V1.3 code as well as the PWR 1300 MWe reference input deck, a wide-ranging series of comparisons with the French best-estimate thermal-hydraulic code CATHARE 2 V2.5 has been performed on 14 different severe-accident scenarios. The present paper details 4 out of the 14 studied scenarios: a 12-in. cold leg Loss of Coolant Accident (LOCA), a 2-tube Steam Generator Tube Rupture (SGTR), a 12-in. Steam Line Break (SLB) and a total Loss of Feed Water scenario (LFW). The thermal-hydraulic behavior of the primary and secondary circuits is thoroughly investigated and compared to the CATAHRE 2 V2.5 results. The ASTEC results of the core degradation phase are also presented. Overall, the thermal-hydraulic behavior given by the ASTEC V1.3 is in very good agreement with the CATHARE 2 V2.5 results.

Methodology for seismic PSA of NPPs

International Nuclear Information System (INIS)

Jirsa, P.

1999-09-01

A general methodology is outlined for seismic PSA (probabilistic safety assessment). The main objectives of seismic PSA include: description of the course of an event; understanding the most probable failure sequences; gaining insight into the overall probability of reactor core damage; identification of the main seismic risk contributors; identification of the range of peak ground accelerations contributing significantly to the plant risk; and comparison of the seismic risk with risks from other events. The results of seismic PSA are typically compared with those of internal PSA and of PSA of other external events. If the results of internal and external PSA are available, sensitivity studies and cost benefit analyses are performed prior to any decision regarding corrective actions. If the seismic PSA involves analysis of the containment, useful information can be gained regarding potential seismic damage of the containment. (P.A.)

PSA applications. Good practices and documentation

International Nuclear Information System (INIS)

Dewailly, J.; Magne, L.

1997-10-01

In this paper, it is shown what the condensed documentation of the main strategic choices and technical assumptions related to a PSA could contain: how to select the internal and external initiating events, how the detail the plant configuration and the general organization of the plant and operating staff, how to highlight the assumptions related to physical models, etc. The proposals in this documentation are based on the R and D D's experience with PSA (construction of PSA models, use of PSA models for operation or maintenance, PSA tools). This document also presents different types of rules or recommendations related to PSA modelling for various applications involved in nuclear power plant operating. Finally, the paper stresses the main difficulties encountered (appropriate use of uncertainties, communication of PSA results to non-specialist users) and it also outlines some prospects for the future. (author)

Measurement of serum isoform [-2]proPSA derivatives shows superior accuracy to magnetic resonance imaging in the diagnosis of prostate cancer in patients with a total prostate-specific antigen level of 2-10 ng/ml.

Science.gov (United States)

Furuya, Kazuhiro; Kawahara, Takashi; Narahara, Masaki; Tokita, Takashi; Fukui, Sachi; Imano, Masashi; Mitome, Taku; Ito, Yusuke; Izumi, Koji; Osaka, Kimito; Yokomizo, Yumiko; Hayashi, Narihiko; Hasumi, Hisashi; Nawata, Shintaro; Kawano, Tsuyoshi; Yao, Masahiro; Uemura, Hiroji

2017-08-01

More accurate diagnostic procedures for prostate cancer are needed to avoid unnecessary biopsy due to the low specificity of prostate-specific antigen (PSA). Recent studies showed that the percentage of serum isoform [-2]proPSA (p2PSA) to free PSA (%p2PSA), the Prostate Health Index (PHI) and magnetic resonance imaging (MRI) were more accurate than PSA. The aim of this study was to test the accuracy of %p2PSA, PHI and MRI in discriminating patients with and without prostate cancer. The subjects were 50 consecutive men with a PSA level of 2.0-10.0 ng/ml, who underwent prostate biopsy from October 2012 to July 2014. These patients underwent multiparametric MRI before biopsy, and their serum samples were measured for PSA, free PSA and p2PSA. The sensitivity, specificity and accuracy of PHI, %p2PSA and MRI were compared with PSA in the diagnosis of biopsy-confirmed prostate cancer. In a univariate analysis, %p2PSA [area under the curve (AUC): 0.811] and PHI (AUC 0.795) were more accurate than MRI (AUC: 0.583) and PSA (AUC: 0.554) for prostate cancer detection. At 60% sensitivity, the specificity of PHI (76.5%) was higher than that of MRI (52.9%). For significant cancer detection, %p2PSA (AUC: 0.745), PHI (AUC: 0.791) and MRI (AUC: 0.739) were marginally more accurate than PSA (AUC: 0.696). At 85% sensitivity, the specificity of MRI (62.1%) was higher than that of PHI (34.5%). PHI and %p2PSA can be used for screening the general population and MRI can be used for detection of significant cancer in patients suspected, from screening tests, of having prostate cancer.

[PSA interest and prostatitis: literature review].

Science.gov (United States)

Bruyère, F; Amine Lakmichi, M

2013-12-01

Prostatitis is easily diagnosed but sometimes associated with PSA measurement. An increased PSA in an asymptomatic patient may be associated with antibiotic use to eliminate the inflammatory part and to confirm prostate biopsy. It seems interesting to confirm or infirm these attitudes with a systematic review of the literature We performed a literature review using the words [prostatitis], [acute prostatitis], [prostate specific antigen], [PSA], in the MEDLINE, Pubmed and AMBASE database searching for articles in French or English published in the past 20 years. PSA is not always increased during an acute prostatitis episode. An increased PSA in an asymptomatic man does not seem to be systematically correlated to prostate inflammation. Analyzing the studies, it seems inaccurate to measure PSA value during a febrile urinary infection episode in men. Systematic use of antibiotic to decrease PSA and not performing prostate biopsy is not relevant and may induce resistance to antibiotic and doesn't induce a reduction risk of having prostate biopsy. PSA is unnecessary in case of febrile urinary tract infection in men. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

The PSA assessment of Defense in Depth Memorandum and proposals

International Nuclear Information System (INIS)

Fiorini, Gian-Luigi; La Rovere, Stefano

2016-01-01

This report concerns the peculiar roles of the Defence-in-Depth (DiD) concept and the Probabilistic Safety Assessment (PSA) approach for the optimization of the safety performances of the nuclear installation. It proposes a conceptual framework and related process for the assessment of the 'safety architecture' implementing DiD, which is articulated in four main steps devoted to (1) the formulation of the safety objectives, (2) the identification of loads and environmental conditions, (3) the representation of the safety architecture and (4) the evaluation of the physical performance and reliability of the levels of DiD. A final additional step achieves the practical assessment of the safety architecture and the corresponding DiD with the support of the PSA. The comprehensive safety assessment of the implemented architecture needs its multi-dimensional representation, i.e. for given initiating event, sequence of possible failures, affected safety function and level of DiD. The risk space (frequency/probability of occurrence, versus consequences) is the framework for the integration between the DiD concept and the PSA approach. Additional qualitative key-notions are introduced in order to address the compliance of the safety architecture with a number of international safety requirements. In this context, the role of the PSA is no longer limited to the verification of the fulfilment of probabilistic targets but includes different contributions to the assessment of the DiD identified in this report. (authors)

External Events PSA for the Paks NPP

International Nuclear Information System (INIS)

Bareith, Attila; Karsa, Zoltan; Siklossy, Tamas; Vida, Zoltan

2014-01-01

Initially, probabilistic safety assessment of external events was limited to the analysis of earthquakes for the Paks Nuclear Power Plant in Hungary. The level 1 seismic PSA was completed in 2002 showing a significant contribution of seismic failures to core damage risk. Although other external events of natural origin had previously been screened out from detailed plant PSA mostly on the basis of event frequencies, a review of recent experience on extreme weather phenomena made during the periodic safety review of the plant led to the initiation of PSA for external events other than earthquakes in 2009. In the meantime, the accident of the Fukushima Dai-ichi Nuclear Power Plant confirmed further the importance of such an analysis. The external event PSA for the Paks plant followed the commonly known steps: selection and screening of external hazards, hazard assessment for screened-in external events, analysis of plant response and fragility, PSA model development, and risk quantification and interpretation of results. As a result of event selection and screening the following weather related external hazards were subject to detailed analysis: extreme wind, extreme rainfall (precipitation), extreme snow, extremely high and extremely low temperatures, lightning, frost and ice formation. The analysis proved to be a significant challenge due to scarcity of data, lack of knowledge, as well as limitations of existing PSA methodologies. This paper presents an overview of the external events PSA performed for the Paks NPP. Important methodological aspects are summarised. Key analysis findings and unresolved issues that need further elaboration are highlighted. Development of external events PSA for the Paks NPP was completed by the end of 2012. The analysis followed the commonly known steps: selection and screening of external hazards, hazard assessment for screened-in external events, analysis of plant response and fragility, PSA model development, and risk

Time from first detectable PSA following radical prostatectomy to biochemical recurrence: A competing risk analysis

Science.gov (United States)

de Boo, Leonora; Pintilie, Melania; Yip, Paul; Baniel, Jack; Fleshner, Neil; Margel, David

2015-01-01

Introduction: In this study, we estimated the time from first detectable prostate-specific antigen (PSA) following radical prostatectomy (RP) to commonly used definitions of biochemical recurrence (BCR). We also identified the predictors of time to BCR. Methods: We identified subjects who underwent a RP and had an undetectable PSA after surgery followed by at least 1 detectable PSA between 2000 and 2011. The primary outcome was time to BCR (PSA ≥0.2 and successive PSA ≥0.2) and prediction of the rate of PSA rise. Outcomes were calculated using a competing risk analysis, with univariable and multivariable Fine and Grey models. We employed a mixed effect model to test clinical predictors that are associated with the rate of PSA rise. Results: The cohort included 376 patients. The median follow-up from surgery was 60.5 months (interquartile range [IQR] 40.8–91.5) and from detectable PSA was 18 months (IQR 11–32). Only 45.74% (n = 172) had PSA values ≥0.2 ng/mL, while 15.16% (n = 57) reached the PSA level of ≥0.4 ng/mL and rising. On multivariable analysis, the values of the first detectable PSA and pathologic Gleason grade 8 or higher were consistently independent predictors of time to BCR. In the mixed effect model rate, the PSA rise was associated with time from surgery to first detectable PSA, Gleason score, and prostate volume. The main limitation of this study is the large proportion of patients that received treatment without reaching BCR. It is plausible that shorter estimated median times would occur at a centre that does not use salvage therapy at such an early state. Conclusion: The time from first detectable PSA to BCR may be lengthy. Our analyses of the predictors of the rate of PSA rise can help determine a personalized approach for patients with a detectable PSA after surgery. PMID:25624961

A methodology for PSA model validation

International Nuclear Information System (INIS)

Unwin, S.D.

1995-09-01

This document reports Phase 2 of work undertaken by Science Applications International Corporation (SAIC) in support of the Atomic Energy Control Board's Probabilistic Safety Assessment (PSA) review. A methodology is presented for the systematic review and evaluation of a PSA model. These methods are intended to support consideration of the following question: To within the scope and depth of modeling resolution of a PSA study, is the resultant model a complete and accurate representation of the subject plant? This question was identified as a key PSA validation issue in SAIC's Phase 1 project. The validation methods are based on a model transformation process devised to enhance the transparency of the modeling assumptions. Through conversion to a 'success-oriented' framework, a closer correspondence to plant design and operational specifications is achieved. This can both enhance the scrutability of the model by plant personnel, and provide an alternative perspective on the model that may assist in the identification of deficiencies. The model transformation process is defined and applied to fault trees documented in the Darlington Probabilistic Safety Evaluation. A tentative real-time process is outlined for implementation and documentation of a PSA review based on the proposed methods. (author). 11 refs., 9 tabs., 30 refs

Report 2: Guidance document on practices to model and implement external flooding hazards in extended PSA

International Nuclear Information System (INIS)

Rebour, V.; Georgescu, G.; Leteinturier, D.; Raimond, E.; La Rovere, S.; Bernadara, P.; Vasseur, D.; Brinkman, H.; Groudev, P.; Ivanov, I.; Turschmann, M.; Sperbeck, S.; Potempski, S.; Hirata, K.; Kumar, Manorma

2016-01-01

This report provides a review of existing practices to model and implement external flooding hazards in existing level 1 PSA. The objective is to identify good practices on the modelling of initiating events (internal and external hazards) with a perspective of development of extended PSA and implementation of external events modelling in extended L1 PSA, its limitations/difficulties as far as possible. The views presented in this report are based on the ASAMPSA-E partners' experience and available publications. The report includes discussions on the following issues: - how to structure a L1 PSA for external flooding events, - information needed from geosciences in terms of hazards modelling and to build relevant modelling for PSA, - how to define and model the impact of each flooding event on SSCs with distinction between the flooding protective structures and devices and the effect of protection failures on other SSCs, - how to identify and model the common cause failures in one reactor or between several reactors, - how to apply HRA methodology for external flooding events, - how to credit additional emergency response (post-Fukushima measures like mobile equipment), - how to address the specific issues of L2 PSA, - how to perform and present risk quantification. (authors)

Association of GPs' risk attitudes, level of empathy, and burnout status with PSA testing in primary care

DEFF Research Database (Denmark)

Pedersen, Anette F; Carlsen, Anders H; Vedsted, Peter

2015-01-01

Denne artikel undersøger, om variationen i raten af PSA-tests mellem alment praktiserende læger kan forklares af psykologiske faktorer som f.eks. lægens risikovillighed. Resultaterne viser, at lægens risikovillighed influerer på raten af PSA-tests. Forfatterne finder blandt andet, at patienter, som...... er registreret hos en læge med mange bekymringer for fejlbehandlinger, har større sandsynlighed for at få taget en PSA-test. Patienter, som er registreret hos en læge, som har en høj tolerance for flertydighed i lægearbejdet, har derimod mindre sandsynlighed for at få foretaget en PSA-test. Patienter......, som er registreret hos en læge med høj tolerance for flertydighed eller en tilbøjelighed til risikobetonet adfærd, har en mindre sandsynlighed for at få gentaget en tidligere normal PSA-test. Undersøgelsen bygger på spørgeskemabesvarelser fra 129 alment solo-praktiserende læger i Region Midtjylland...

PSA use in accident management studies in Japan

International Nuclear Information System (INIS)

Hirano, Mitsumasa

1994-01-01

The safety of NPPs in Japan is secured by stringent safety regulations based on the deterministic method, minimizing the possibility a severe accident to a technologically negligible level. PSA is not required in the current regulatory procedures. Accident management based on PSA is a 'knowledge-based' action dependent on utilities' technical knowledge aimed at further reduction of the risk which is kept small enough by existing measures. The paper discusses the following three kinds of PSAs that have been conducted practically and efficiently on NPPs to provide supplemental information about their safety characteristics in addition to the deterministic evaluation used in the regulatory safety review: PSAs on typical NPPs, PSAs on all NPPs to examine candidates for accident management, and PSAs as part of periodic safety review (PSR). 1 fig., 5 tabs

Predictive value of [-2]propsa (p2psa and its derivatives for the prostate cancer detection in the 2.0 to 10.0ng/mL PSA range

Directory of Open Access Journals (Sweden)

I. Vukovic

Full Text Available ABSTRACT Introduction To assess predictive value of new tumor markers, precursor of prostate specific antigen (p2PSA and its derivates-%p2PSA and prostate health index (PHI in detection of patients with indolent and aggressive prostate cancer (PC in a subcohort of man whose total PSA ranged from 2 to 10ng/mL. Materials and Methods This cross-sectional study included 129 consecutive male patients aged over 50 years, with no previous history of PC and with normal digital rectal examination findings, but with serum PSA in interval between 2 and 10ng/mL. All patients underwent standard transrectal ultrasonography guided prostate biopsy for the first time. For all patients, serum PSA, free PSA (fPSA and p2PSA were measured and PHI and %p2PSA were calculated. Results PHI and %p2PSA levels were significanlty higher in patients with PC compared to those without this malignancy. The same findings have been observed in group of patients with Gleason score ≥7 compared to those with Gleason score <7. ROC analysis reveled the highest area under the curve with these two markers. Multivariate logistic regression showed significant improvement in PC detection and its agressive form (assumed as Gleason score ≥7. Conclusions New markers, derivates of p2PSA (especially %p2PSA and PHI, represente potentially very important clinical tool for predicting presence of PC, and even more important, to discriminate patients with Gleason score <7 from those with Gleason score ≥7 with total PSA in range from 2 to 10ng/mL.

Predictive value of [-2]propsa (p2psa) and its derivatives for the prostate cancer detection in the 2.0 to 10.0ng/mL PSA range.

Science.gov (United States)

Vukovic, I; Djordjevic, D; Bojanic, N; Babic, U; Soldatovic, I

2017-01-01

To assess predictive value of new tumor markers, precursor of prostate specific antigen (p2PSA) and its derivates-%p2PSA and prostate health index (PHI) in detection of patients with indolent and aggressive prostate cancer (PC) in a subcohort of man whose total PSA ranged from 2 to 10ng/mL. This cross-sectional study included 129 consecutive male patients aged over 50 years, with no previous history of PC and with normal digital rectal examination findings, but with serum PSA in interval between 2 and 10ng/mL. All patients underwent standard transrectal ultrasonography guided prostate biopsy for the first time. For all patients, serum PSA, free PSA (fPSA) and p2PSA were measured and PHI and %p2PSA were calculated. PHI and %p2PSA levels were significanlty higher in patients with PC compared to those without this malignancy. The same findings have been observed in group of patients with Gleason score ≥7 compared to those with Gleason score <7. ROC analysis reveled the highest area under the curve with these two markers. Multivariate logistic regression showed significant improvement in PC detection and its agressive form (assumed as Gleason score ≥7). New markers, derivates of p2PSA (especially %p2PSA and PHI), represente potentially very important clinical tool for predicting presence of PC, and even more important, to discriminate patients with Gleason score <7 from those with Gleason score ≥7 with total PSA in range from 2 to 10ng/mL. Copyright® by the International Brazilian Journal of Urology.

A preliminary investigation of PSA validation methods

Energy Technology Data Exchange (ETDEWEB)

Unwin, S D [Science Applications International Corp., (United States)

1995-09-01

This document has been prepared to support the initial phase of the Atomic Energy Control Board`s program to review and evaluate Probabilistic Safety Assessment (PSA) studies conducted by nuclear generating station designers and licensees. The document provides (1) a review of current and prospective applications of PSA technology in the Canadian nuclear power industry; (2) an assessment of existing practices and techniques for the review or risk and hazard identification studies in the international nuclear power sector and other technological sectors; and (3) proposed analytical framework in which to develop systematic techniques for the scrutiny and evaluation of a PSA model. These frameworks are based on consideration of the mathematical structure of a PSA model and are intended to facilitate the development of methods to evaluate a model relative to intended end-uses. (author). 34 refs., 10 tabs., 3 figs.

A preliminary investigation of PSA validation methods

International Nuclear Information System (INIS)

Unwin, S.D.

1995-09-01

This document has been prepared to support the initial phase of the Atomic Energy Control Board's program to review and evaluate Probabilistic Safety Assessment (PSA) studies conducted by nuclear generating station designers and licensees. The document provides (1) a review of current and prospective applications of PSA technology in the Canadian nuclear power industry; (2) an assessment of existing practices and techniques for the review or risk and hazard identification studies in the international nuclear power sector and other technological sectors; and (3) proposed analytical framework in which to develop systematic techniques for the scrutiny and evaluation of a PSA model. These frameworks are based on consideration of the mathematical structure of a PSA model and are intended to facilitate the development of methods to evaluate a model relative to intended end-uses. (author). 34 refs., 10 tabs., 3 figs

Status and use of PSA in Sweden

International Nuclear Information System (INIS)

Knochenhauer, M.

1996-05-01

The performance and use of PSA:s in Sweden goes back about two decades. During all of this time, the field of PSA has been developing intensively, both internationally and within Sweden. The latest years have been characterised by an increased use of PSA models and results, and by major extensions of existing PSA models. The aim of this document is to describe PSA in Sweden with respect to development, scope and maturity, as well as to the contents of the analyses and the use of results. PSA activities will be described from the point of view of both the authorities and the utilities. The report gives an overview of the development within the area of PSA in Sweden both its history and current trends. The aim has been to include a reasonable amount of detail, both on the methods and results in PSA:s performed and on the numerous supporting research programs dealing with various aspects of PSA. 39 refs 39 refs

Status and use of PSA in Sweden

Energy Technology Data Exchange (ETDEWEB)

Knochenhauer, M

1996-05-01

The performance and use of PSA:s in Sweden goes back about two decades. During all of this time, the field of PSA has been developing intensively, both internationally and within Sweden. The latest years have been characterised by an increased use of PSA models and results, and by major extensions of existing PSA models. The aim of this document is to describe PSA in Sweden with respect to development, scope and maturity, as well as to the contents of the analyses and the use of results. PSA activities will be described from the point of view of both the authorities and the utilities. The report gives an overview of the development within the area of PSA in Sweden both its history and current trends. The aim has been to include a reasonable amount of detail, both on the methods and results in PSA:s performed and on the numerous supporting research programs dealing with various aspects of PSA. 39 refs 39 refs.

Programmable automation systems in PSA

International Nuclear Information System (INIS)

Pulkkinen, U.

1997-06-01

The Finnish safety authority (STUK) requires plant specific PSAs, and quantitative safety goals are set on different levels. The reliability analysis is more problematic when critical safety functions are realized by applying programmable automation systems. Conventional modeling techniques do not necessarily apply to the analysis of these systems, and the quantification seems to be impossible. However, it is important to analyze contribution of programmable automation systems to the plant safety and PSA is the only method with system analytical view over the safety. This report discusses the applicability of PSA methodology (fault tree analyses, failure modes and effects analyses) in the analysis of programmable automation systems. The problem of how to decompose programmable automation systems for reliability modeling purposes is discussed. In addition to the qualitative analysis and structural reliability modeling issues, the possibility to evaluate failure probabilities of programmable automation systems is considered. One solution to the quantification issue is the use of expert judgements, and the principles to apply expert judgements is discussed in the paper. A framework to apply expert judgements is outlined. Further, the impacts of subjective estimates on the interpretation of PSA results are discussed. (orig.) (13 refs.)

PSA results and trends for Spain's NPPs

International Nuclear Information System (INIS)

Carretero, J.A.

1993-01-01

The Spain regulatory authority CSN demanded performance of PSA for all Spain nuclear power plants. The specific data analysis carried out as a part of the PSA has contributed to the realistic view on the results which could be achieved by the PSA. The main characteristics of the PSA in Spain and PSA trends in the development are presented in the paper

Tools for PSA reviews

International Nuclear Information System (INIS)

Linden, J. von

1998-01-01

It is desirable to have a uniform and competent procedure for the review of PSAs which are performed within the framework of the Periodic Safety Review of German Nuclear Power Plants. Guidelines for the review process should therefore be evaluated within task A. 1 of project SR 2096. The basis for this work is the experience and knowledge within GRS derived from PSA-related work and from several review projects as well as the German PSA Guide with its appendices. Furthermore, the review processes in the USA, Switzerland and Sweden and the Guidelines for the International Peer Review Service (IPERS Guidelines) were utilized. As a result, recommendations are given for the review process, with individual recommendations concerning the organization of the review, task allocation between the reviewers, interface problems, assessment criteria, the scope and depth of the review as well as the supporting documents. An additional result are checklists for the technical elements of the PSA, which are listed to facilicate the review work. It is not the intention of this report to work out complete review guidelines. Its aims is rather more to give recommondations and support for the review in addition to what can be derived from the existing documents that should be used for the review. The recommendations reflect the view of GRS and go beyond the statements given in the German PSA Guide (Leitfaden Probabilistische Sicherheitsanalyse /PSUe97/) in some points. (orig.) [de

Implementation guidelines for seismic PSA

International Nuclear Information System (INIS)

Coman, Ovidiu; Samaddar, Sujit; Hibino, Kenta; )

2014-01-01

The presentation was devoted to development of guidelines for implementation of a seismic PSA. If successful, these guidelines can close an important gap. ASME/ANS PRA standards and the related IAEA Safety Guide (IAEA NS-G-2.13) describe capability requirements for seismic PSA in order to support risk-informed applications. However, practical guidance on how to meet these requirements is limited. Such guidelines could significantly contribute to improving risk-informed safety demonstration, safety management and decision making. Extensions of this effort to further PSA areas, particularly to PSA for other external hazards, can enhance risk-informed applications

UV/EB curable psa's

International Nuclear Information System (INIS)

Glotfelter, C.A.

1995-01-01

The author describe both water-based and 100% solids UV/EB curable PSA's (Pressure Sensitive Adhesives) and their properties. A new acrylate monomer, ethoxylated nonyl phenol acrylate, has great utility in the formulation of water-based PSA's

THE DISCRIMINATIVE ABILITY OF PERCENT FREE PSA IN ...

African Journals Online (AJOL)

Blood samples were collected from all patients, and total PSA, free PSA and % free PSA were calculated in all specimens. Total PSA was measured using the Imx ... Un prélèvement de sang a été réalisé chez tous les patients avec un dosage du PSA total et de la fraction libre de PSA. Le PSA total a été mesuré par un kit ...

PSA time to nadir as a prognostic factor of first-line docetaxel treatment in castration-resistant prostate cancer: evidence from patients in Northwestern China.

Science.gov (United States)

Wu, Kai-Jie; Pei, Xin-Qi; Tian, Ge; Wu, Da-Peng; Fan, Jin-Hai; Jiang, Yu-Mei; He, Da-Lin

2018-01-01

Docetaxel-based chemotherapy remains the first-line treatment for patients with metastatic castration-resistant prostate cancer (mCRPC) in China; however, the prognostic factors associated with effects in these patients are still controversial. In this study, we retrospectively reviewed the data from 71 eligible Chinese patients who received docetaxel chemotherapy from 2009 to 2016 in our hospital and experienced a reduction of prostate-specific antigen (PSA) level ≥50% during the treatment and investigated the potential role of time to nadir (TTN) of PSA. TTN was defined as the time from start of chemotherapy to the nadir of PSA level during the treatment. Multivariable Cox regression models and Kaplan-Meier analysis were used to predict overall survival (OS). In these patients, the median of TTN was 17 weeks. Patients with TTN ≥17 weeks had a longer response time to chemotherapy compared to TTN PSA progression in patients with TTN ≥17 weeks was 11.44 weeks compared to 5.63 weeks when TTN was PSA level at the diagnosis of cancer (HR: 4.337, 95% CI: 1.616-11.645, P = 0.004), duration of initial androgen deprivation therapy (HR: 2.982, 95% CI: 1.104-8.045, P = 0.031), neutrophil-to-lymphocyte ratio (HR: 3.963, 95% CI: 1.380-11.384, P = 0.011), and total PSA response (Class 1 [PSA remains an important prognostic marker in predicting therapeutic outcome in Chinese population who receive chemotherapy for mCRPC and have >50% PSA remission.

Insulin promotes cell migration by regulating PSA-NCAM

Energy Technology Data Exchange (ETDEWEB)

Monzo, Hector J.; Coppieters, Natacha [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Park, Thomas I.H. [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Pharmacology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Dieriks, Birger V.; Faull, Richard L.M. [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Dragunow, Mike [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Pharmacology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Curtis, Maurice A., E-mail: m.curtis@auckland.ac.nz [Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand); Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, 92019, Auckland (New Zealand)

2017-06-01

Cellular interactions with the extracellular environment are modulated by cell surface polysialic acid (PSA) carried by the neural cell adhesion molecule (NCAM). PSA-NCAM is involved in cellular processes such as differentiation, plasticity, and migration, and is elevated in Alzheimer's disease as well as in metastatic tumour cells. Our previous work demonstrated that insulin enhances the abundance of cell surface PSA by inhibiting PSA-NCAM endocytosis. In the present study we have identified a mechanism for insulin-dependent inhibition of PSA-NCAM turnover affecting cell migration. Insulin enhanced the phosphorylation of the focal adhesion kinase leading to dissociation of αv-integrin/PSA-NCAM clusters, and promoted cell migration. Our results show that αv-integrin plays a key role in the PSA-NCAM turnover process. αv-integrin knockdown stopped PSA-NCAM from being endocytosed, and αv-integrin/PSA-NCAM clusters co-labelled intracellularly with Rab5, altogether indicating a role for αv-integrin as a carrier for PSA-NCAM during internalisation. Furthermore, inhibition of p-FAK caused dissociation of αv-integrin/PSA-NCAM clusters and counteracted the insulin-induced accumulation of PSA at the cell surface and cell migration was impaired. Our data reveal a functional association between the insulin/p-FAK-dependent regulation of PSA-NCAM turnover and cell migration through the extracellular matrix. Most importantly, they identify a novel mechanism for insulin-stimulated cell migration. - Highlights: • Insulin modulates PSA-NCAM turnover through upregulation of p-FAK. • P-FAK modulates αv-integrin/PSA-NCAM clustering. • αv-integrin acts as a carrier for PSA-NCAM endocytosis. • Cell migration is promoted by cell surface PSA. • Insulin promotes PSA-dependent migration in vitro.

Insulin promotes cell migration by regulating PSA-NCAM

International Nuclear Information System (INIS)

Monzo, Hector J.; Coppieters, Natacha; Park, Thomas I.H.; Dieriks, Birger V.; Faull, Richard L.M.; Dragunow, Mike; Curtis, Maurice A.

2017-01-01

Cellular interactions with the extracellular environment are modulated by cell surface polysialic acid (PSA) carried by the neural cell adhesion molecule (NCAM). PSA-NCAM is involved in cellular processes such as differentiation, plasticity, and migration, and is elevated in Alzheimer's disease as well as in metastatic tumour cells. Our previous work demonstrated that insulin enhances the abundance of cell surface PSA by inhibiting PSA-NCAM endocytosis. In the present study we have identified a mechanism for insulin-dependent inhibition of PSA-NCAM turnover affecting cell migration. Insulin enhanced the phosphorylation of the focal adhesion kinase leading to dissociation of αv-integrin/PSA-NCAM clusters, and promoted cell migration. Our results show that αv-integrin plays a key role in the PSA-NCAM turnover process. αv-integrin knockdown stopped PSA-NCAM from being endocytosed, and αv-integrin/PSA-NCAM clusters co-labelled intracellularly with Rab5, altogether indicating a role for αv-integrin as a carrier for PSA-NCAM during internalisation. Furthermore, inhibition of p-FAK caused dissociation of αv-integrin/PSA-NCAM clusters and counteracted the insulin-induced accumulation of PSA at the cell surface and cell migration was impaired. Our data reveal a functional association between the insulin/p-FAK-dependent regulation of PSA-NCAM turnover and cell migration through the extracellular matrix. Most importantly, they identify a novel mechanism for insulin-stimulated cell migration. - Highlights: • Insulin modulates PSA-NCAM turnover through upregulation of p-FAK. • P-FAK modulates αv-integrin/PSA-NCAM clustering. • αv-integrin acts as a carrier for PSA-NCAM endocytosis. • Cell migration is promoted by cell surface PSA. • Insulin promotes PSA-dependent migration in vitro.

Prevalence and causes of abnormal PSA recovery.

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Lautenbach, Noémie; Müntener, Michael; Zanoni, Paolo; Saleh, Lanja; Saba, Karim; Umbehr, Martin; Velagapudi, Srividya; Hof, Danielle; Sulser, Tullio; Wild, Peter J; von Eckardstein, Arnold; Poyet, Cédric

2018-01-26

Prostate-specific antigen (PSA) test is of paramount importance as a diagnostic tool for the detection and monitoring of patients with prostate cancer. In the presence of interfering factors such as heterophilic antibodies or anti-PSA antibodies the PSA test can yield significantly falsified results. The prevalence of these factors is unknown. We determined the recovery of PSA concentrations diluting patient samples with a standard serum of known PSA concentration. Based on the frequency distribution of recoveries in a pre-study on 268 samples, samples with recoveries 120% were defined as suspect, re-tested and further characterized to identify the cause of interference. A total of 1158 consecutive serum samples were analyzed. Four samples (0.3%) showed reproducibly disturbed recoveries of 10%, 68%, 166% and 4441%. In three samples heterophilic antibodies were identified as the probable cause, in the fourth anti-PSA-autoantibodies. The very low recovery caused by the latter interference was confirmed in serum, as well as heparin- and EDTA plasma of blood samples obtained 6 months later. Analysis by eight different immunoassays showed recoveries ranging between PSA which however did not show any disturbed PSA recovery. About 0.3% of PSA determinations by the electrochemiluminescence assay (ECLIA) of Roche diagnostics are disturbed by heterophilic or anti-PSA autoantibodies. Although they are rare, these interferences can cause relevant misinterpretations of a PSA test result.

Image Guided Hypofractionated Radiotherapy by Helical Tomotherapy for Prostate Carcinoma: Toxicity and Impact on Nadir PSA

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Salvina Barra

2014-01-01

Full Text Available Aim. To evaluate the toxicity of a hypofractionated schedule for primary radiotherapy (RT of prostate cancer as well as the value of the nadir PSA (nPSA and time to nadir PSA (tnPSA as surrogate efficacy of treatment. Material and Methods. Eighty patients underwent hypofractionated schedule by Helical Tomotherapy (HT. A dose of 70.2 Gy was administered in 27 daily fractions of 2.6 Gy. Acute and late toxicities were graded on the RTOG/EORTC scales. The nPSA and the tnPSA for patients treated with exclusive RT were compared to an equal cohort of 20 patients treated with conventional fractionation and standard conformal radiotherapy. Results. Most of patients (83% did not develop acute gastrointestinal (GI toxicity and 50% did not present genitourinary (GU toxicity. After a median follow-up of 36 months only grade 1 of GU and GI was reported in 6 and 3 patients as late toxicity. Average tnPSA was 30 months. The median value of nPSA after exclusive RT with HT was 0.28 ng/mL and was significantly lower than the median nPSA (0.67 ng/mL of the conventionally treated cohort (P=0.02. Conclusions. Hypofractionated RT schedule with HT for prostate cancer treatment reports very low toxicity and reaches a low level of nPSA that might correlate with good outcomes.

Report 5: Guidance document. Implementation of biological infestation hazards in extended PSA

International Nuclear Information System (INIS)

Hasnaoui, C.; Georgescu, G.; Joel, P.; Sperbeck, S.; Kollasko, H.; Kumar, M.

2016-01-01

This report covers the assessment of biological hazards with PSA. It provides an overview of the available data and available practices in modelling this type of hazard. First researches in the national and international literature regarding PSA for external and internal hazards shows that probabilistic analyses were very rarely carried out in order to quantify the risk induced by biological hazards. Nevertheless, Section 3 provides some data from some countries. History has shown that this hazard can happened and can be highly safety significant. Screening out this event must be done with great care. The overall analysis approach for Level 1 PSA for internal events can be used for the biological hazards with some care to take into impact the nature of the hazard as it impacts many systems at different times and duration. A proposed detailed methodology is described in Section 4. Still some open issues remain: the methodology must also consider event combination of biological infestation with other external hazards wind or flooding or rainfall and multi-units impact. These aspects present still a lot of challenges to PSA developers. The ASAMPSA-E report recommends that further emphasis shall be put on these two aspects of PSA modelling: multi-units site impact and hazards combinations. (authors)

Pretreatment PSA predicts for biochemical disease free survival in patients treated with post-prostatectomy external beam irradiation

International Nuclear Information System (INIS)

Crane, C.H.; Kelly, M.; Rich, T.A.

1996-01-01

Objective: To assess the outcome and determine prognostic factors for patients treated with external beam radiotherapy following radical prostatectomy. Methods and Materials: Forty-four patients were treated after prostatectomy with radiotherapy between March 1988 and October 1993. All patients were free from clinically or radiographically suspicious local or distant disease. One patient underwent neoadjuvant hormonal therapy, but no other patients received hormonal therapy prior to radiation. Pre-radiotherapy PSA and follow-up PSA data were available in all patients. Four patients had undetectable PSA ( 7, and 11% had nodal involvement. Survival was analyzed using the life table method. Actuarial freedom from biochemical (BCM) failure, defined as a rise of greater than 10% or an undetectable PSA becoming detectable, was the primary endpoint studied. Results: Fifty-nine percent of patients had a detectable PSA return to undetectable levels after XRT. The actuarial five year freedom from biochemical failure for all patients was 24%. A significant difference in BCM disease free survival was seen for patients irradiated with a pre-XRT PSA ≤2.7 versus a pre-XRT PSA >2.7 (p=0.0001). Sixty percent of the former group were BCM disease free versus 0% in the latter. Biochemical disease free survival was not affected by preoperative PSA level, presence of undetectable PSA after surgery, surgery to radiation interval, seminal vesicle invasion, clinical stage, pathologic stage, Gleasons grade, or total dose. There were no symptomatic or clinically suspicious local failures, and there were no grade 3, 4, or 5 acute or late complications. There were 69% grade 1 and 2 acute reactions and one grade 2 late complication. Conclusions: Pelvic radiotherapy for patients with a PSA of ≤2.7 after prostatectomy was effective in biochemically controlling 60% of the patients with four years median follow up. To our knowledge these data represent the longest follow-up for this patient

How much does PSA matter after 10 years? Outcomes in 10-year clinical NED survivors after definitive radiotherapy for T1-3N0M0 prostate cancer

International Nuclear Information System (INIS)

Johnstone, Peter A. S.; Powell, Curt; Riffenburgh, Robert; Saunders, Eric L.; Bethel, Kelly J.; Huisman, Thomas

1996-01-01

Objective: Institutional policy in the 1970's and 80's dictated that patients with potentially curable prostate cancer undergo PLND prior to definitive XRT. Our group has reported 80% 15-year actuarial cause-specific survival for the 147 patients so treated. Analysis was made of PSA values and clinical outcomes of patients who were clinically without evidence of disease (NED) 10 years after a negative staging pelvic lymphadenectomy and definitive radiation therapy (XRT) for prostate cancer. Materials and Methods: One hundred patients underwent staging pelvic lymphadenectomy between 11/1/74 and 1/1/86, of which 98 had pathologically negative lymph nodes (N 0 ). These patients subsequently underwent definitive radiotherapy; a median dose of 66.6 Gy (range 63-70.2 Gy) was delivered. Forty-two N 0 patients with sufficient follow-up were alive and clinically NED 10 years post-operatively. None of these patients had ever received hormonal therapy. Distribution by disease stage at diagnosis was: Stage A2: 12 pts; Stage B: 19 pts; Stage B2/ C: 6 pts; Stage C: 5 pts. Median follow-up was 12 years 4 months, with a minimum follow-up of 10 years. Results: Of the 42 NED survivors at 10 years, 5 pts died subsequently without PSA data, remaining clinically NED (median 13y 3m post-operatively); 37 patients were alive and without evidence of disease off all therapy at 10 years post-operatively. Most recent PSA data reveal: Bone scans were performed on the 8 patients with elevated PSA. These revealed a single patient with diffuse but asymptomatic bone metastases. Ultrasound-guided sextant biopsies were performed on one 78-year-old patient with elevated PSA 19 years post-operatively, revealing an asymptomatic local recurrence. Conclusions: Radiation therapy delivered to a surgically staged population of prostate cancer patients contributes to normalization of PSA in 78% ((29(37))) of patients with ≥10 year follow-up. Most of these patients will have PSA levels ≤ 1.5 ng/ml. More

The Role of Level-3 PSA in the Regulatory Structure for the Licensing of Future NPPs

International Nuclear Information System (INIS)

Jeong, Jong Tae; Han, Sang Hoon

2008-01-01

accomplished. Therefore, the role of Level-3 PSA for the evaluation of dose consequences will be examined in this study

The development of integrated safety assessment technology

International Nuclear Information System (INIS)

Yoo, Keon Joong; Park, Chang Kyu; Kim, Tae Un; Han, Sang Hoon; Yang, Joon Eon; Lim, Tae Jin; Han, Jae Joo; Je, Moo Seong; An, Kwang Il; Kim, Shi Dal; Jeong, Jong Tae; Jeong, Kwang Seop; Jin, Yeong Ho; Kim, Dong Ha; Kim, Kil Yoo; Cho, Yeong Kyoon; Jeong, Won Dae; Jang, Seung Cheol; Choi, Yeong; Park, Soo Yong; Seong, Tae Yong; Song, Yong Man; Kang, Dae Il; Park, Jin Hee; Jang, Seon Joo; Hwang, Mi Jeong; Choi, Seon Yeong

1993-05-01

For the purpose of developing the integrated PSA methodology and computer codes, Level-1 and Level-2 PSA methodology and tools were reviewed and improved. The Level-1 PSA computer code package KIRAP was improved and released by the name of KIRAP Release 2.0 Several Human reliability analysis and common cause failure analysis methods was reviewed and compared. For the development of Level-2 PSA computer code, several level-1 and Level-2 interface methods and containment event tree development methods were reviewed and compared. And the new technology such as artificial intelligence was reviewed if the technology can be applied to the development of PSA methodology.(Author)

PSA modeling of long-term accident sequences

International Nuclear Information System (INIS)

Georgescu, Gabriel; Corenwinder, Francois; Lanore, Jeanne-Marie

2014-01-01

In the context of the extension of PSA scope to include external hazards, in France, both operator (EDF) and IRSN work for the improvement of methods to better take into account in the PSA the accident sequences induced by initiators which affect a whole site containing several nuclear units (reactors, fuel pools,...). These methodological improvements represent an essential prerequisite for the development of external hazards PSA. However, it has to be noted that in French PSA, even before Fukushima, long term accident sequences were taken into account: many insight were therefore used, as complementary information, to enhance the safety level of the plants. IRSN proposed an external events PSA development program. One of the first steps of the program is the development of methods to model in the PSA the long term accident sequences, based on the experience gained. At short term IRSN intends to enhance the modeling of the 'long term' accident sequences induced by the loss of the heat sink or/and the loss of external power supply. The experience gained by IRSN and EDF from the development of several probabilistic studies treating long term accident sequences shows that the simple extension of the mission time of the mitigation systems from 24 hours to longer times is not sufficient to realistically quantify the risk and to obtain a correct ranking of the risk contributions and that treatment of recoveries is also necessary. IRSN intends to develop a generic study which can be used as a general methodology for the assessment of the long term accident sequences, mainly generated by external hazards and their combinations. This first attempt to develop this generic study allowed identifying some aspects, which may be hazard (or combinations of hazards) or related to initial boundary conditions, which should be taken into account for further developments. (authors)

[Rates of total and free PSA prescriptions in France (2012-2014)].

Science.gov (United States)

Tuppin, Philippe; Leboucher, Claire; Peyre-Lanquar, Gabrielle; Lamy, Pierre-Jean; Gabach, Pierre; Rébillard, Xavier

2017-10-01

In 2010, the French Haute Autorité de santé (National Health Authority) confirmed the limited value of prostate cancer (PCa) screening by total prostate-specific antigen (PSA) assay. This study was designed to determine the modalities of ordering total PSA or free PSA assays (in the absence of PCa) according to various parameters and the corresponding sums reimbursed. Men aged 40 years and older covered by the national health insurance general scheme (73% of the French population) between 2012 and 2014 were selected. Data were derived from the Système national d'information inter-régimes de l'assurance maladie (Sniiram) (National health insurance information system) database. In 2014, 27% of the 11.6 million men 40 years and older underwent at least one total PSA assay and 5.6% underwent at least one free PSA assay, with marked variations according to the presence or absence of treated lower urinary tract symptoms (LUTS) (53% and 15% vs 24% and 5%) and from one administrative department to another. The peak total PSA assay rate was observed between the ages of 65 and 74 years: 64% of men with LUTS, 46% without LUTS. Between 2012 and 2014, men in whom at least one PSA assay had been performed underwent a mean of 1.8 total PSA assays and 1.7 free PSA assays, with means of 2.3 and 2, respectively, in the presence of LUTS. General practice specialists ordered 91% of the PSA tests reimbursed in 2014 (92% for total PSA and 87% for free PSA) and urologists ordered 4% of reimbursed tests. The total sum reimbursed was €28.5 million, comprising €8.7 million for free PSA. An average of 10 laboratory tests was performed at the same time as the PSA assay in the absence of treated LUTS. Total PSA and free PSA assays are performed in a large number of men, although the value of these tests as first-line test before biopsy remains controversial. These PSA assays are associated with many other laboratory tests looking for possible abnormalities, especially in younger

Regulatory approaches to, and practice of, PSA in Finland, France, Spain, Sweden, Switzerland, the United Kingdom, and the United States of America

International Nuclear Information System (INIS)

Baier, M.; Schaefer, A.

2005-01-01

Performing level-1 probabilistic safety analyses (PSA) is the established standard in most countries using nuclear power. In addition, level-2 PSA has become more and more widespread over the past few years. However, regulatory requirements and practice differ from country to country, especially with respect to level-2 analyses. In an effort to determine these differences more precisely, the ISaR Institute for Safety and Reliability, on behalf of VGB PowerTech Service GmbH, conducted a study of these seven countries: Finland, France, Spain, Sweden, Switzerland, the United Kingdom, and the United States. The study focused on level-2 PSA carried out by plant operators within the framework of periodic safety reviews. The findings of the study are based on extensive interviews of at least one expert each on the operators' and the authorities' side for each of the seven countries. Points taken into account in particular included the criteria imposed by regulators on PSA carried out by operators; the rank of PSA within the regulatory framework; the required versus the actual scopes of analysis; the objectives and uses of PSA; reviews of the analyses; the methods employed. (orig.)

PSA response signatures - a powerful new prognostic indicator after radiation for prostate cancer?

International Nuclear Information System (INIS)

Denham, James W.; Lamb, David S.; Joseph, David; Matthews, John; Atkinson, Chris; Spry, Nigel A.; Duchesne, Gillian; Ebert, Martin; Steigler, Allison; D'Este, Catherine

2009-01-01

Background: We sought to determine whether inter-patient variations in pattern of PSA changes after radiation exist and, if so, are they prognostically significant. Methods: In the Trans-Tasman Radiation Oncology Group (TROG) 96.01 randomized controlled trial, patients with T2b,c,3,4 N0 prostate cancer (PC) were randomised to 0, 3 or 6 months maximal androgen deprivation prior to 66 Gy to the prostate and seminal vesicles (XRT). Patterns of anatomical site of failure were one of the trial endpoints. Serial serum PSA's were mandated at all follow-up visits. Pattern recognition software was developed to characterize PSA response 'signatures' (PRS) after therapy in individual patients. Results: By 2000, 270 eligible patients were randomised to radiation alone. Individual patient PSA values were observed to descend after radiation according to one of two characteristic 'signatures': single exponential (PRS Type 1), non-exponential (PRS Type 2). Compared to PRS Type 1, men with PRS Type 2 (50% of the group) had lower PSA nadir (nPSA) levels (p < .0001), longer doubling times on relapse (p = .006) and significantly lower rates of local (hazard ratio [HR]: 0.47, 95% confidence interval [0.30-0.75], p = .0014) and distant failure (HR: 0.25[0.13-0.46], p < .0001), death due to PC (HR: 0.20[0.10-0.42], p < .0001) and death due to any cause (HR: 0.37 [0.23-0.60], p < .0001). PRS retained its powerful prognostic significance in Cox models that incorporated all key pre-treatment covariates and nPSA. Conclusions: PRS reflect the presence of tumor phenotypes that vary substantially in their clinical behavior and response to XRT. Molecular characterization is now necessary

Metastatic prostate cancer in the modern era of PSA screening

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Philip A. Fontenot Jr

Full Text Available ABSTRACT Introduction To characterize initial presentation and PSA screening status in a contemporary cohort of men treated for metastatic prostate cancer at our institution. Materials and methods We reviewed records of 160 men treated for metastatic prostate cancer between 2008-2014 and assessed initial presentation, categorizing patients into four groups. Groups 1 and 2 presented with localized disease and received treatment. These men suffered biochemical recurrence late (>1 year or earlier (<1 year, respectively, and developed metastases. Groups 3 and 4 had asymptomatic and symptomatic metastases at the outset of their diagnosis. Patients with a first PSA at age 55 or younger were considered to have guideline-directed screening. Results Complete records were available on 157 men for initial presentation and 155 men for PSA screening. Groups 1, 2, 3 and 4 included 27 (17%, 7 (5%, 69 (44% and 54 (34% patients, respectively. Twenty (13% patients received guideline-directed PSA screening, 5/155 (3% patients presented with metastases prior to age 55 with their first PSA, and 130/155 (84% had their first PSA after age 55, of which 122/130 (94% had metastasis at the time of diagnosis. Conclusion Despite widespread screening, most men treated for metastatic prostate cancer at our institution presented with metastases rather than progressed after definitive treatment. Furthermore, 25 (16% patients received guideline-directed PSA screening at or before age 55. These data highlight that, despite mass screening efforts, patients treated for incurable disease at our institution may not have been a result of a failed screening test, but a failure to be screened.

Metastatic prostate cancer in the modern era of PSA screening

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Fontenot, Philip A.; Nehra, Avinash; Parker, William; Wyre, Hadley; Mirza, Moben; Duchene, David A.; Holzbeierlein, Jeffrey; Thrasher, James Brantley; Veldhuizen, Peter Van; Lee, Eugene K.

2017-01-01

ABSTRACT Introduction To characterize initial presentation and PSA screening status in a contemporary cohort of men treated for metastatic prostate cancer at our institution. Materials and methods We reviewed records of 160 men treated for metastatic prostate cancer between 2008-2014 and assessed initial presentation, categorizing patients into four groups. Groups 1 and 2 presented with localized disease and received treatment. These men suffered biochemical recurrence late (>1 year) or earlier (<1 year), respectively, and developed metastases. Groups 3 and 4 had asymptomatic and symptomatic metastases at the outset of their diagnosis. Patients with a first PSA at age 55 or younger were considered to have guideline-directed screening. Results Complete records were available on 157 men for initial presentation and 155 men for PSA screening. Groups 1, 2, 3 and 4 included 27 (17%), 7 (5%), 69 (44%) and 54 (34%) patients, respectively. Twenty (13%) patients received guideline-directed PSA screening, 5/155 (3%) patients presented with metastases prior to age 55 with their first PSA, and 130/155 (84%) had their first PSA after age 55, of which 122/130 (94%) had metastasis at the time of diagnosis. Conclusion Despite widespread screening, most men treated for metastatic prostate cancer at our institution presented with metastases rather than progressed after definitive treatment. Furthermore, 25 (16%) patients received guideline-directed PSA screening at or before age 55. These data highlight that, despite mass screening efforts, patients treated for incurable disease at our institution may not have been a result of a failed screening test, but a failure to be screened. PMID:28338310

Hand Hygiene in Healthcare Settings 1 PSA (:30)