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1.
Dent Med Probl ; 61(4): 479-480, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39150238

RESUMO

The International Agency for Research on Cancer (IARC) "Handbook of Oral Cancer Prevention", vol. 19, provides a thorough and comprehensive evidence-based evaluation of primary and secondary prevention interventions for oral cancer.


Assuntos
Neoplasias Bucais , Humanos , Neoplasias Bucais/prevenção & controle , Agências Internacionais , Prevenção Primária , Prevenção Secundária
2.
Phys Med ; 124: 103431, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39059250

RESUMO

PURPOSE: The objective of our IAEA-coordinated international study was to assess CT practices and radiation doses from multiple hospitals across several African countries. METHODS: The study included 13 hospitals from Africa which contributed information on minimum of 20 consecutive patients who underwent head, chest, and/or abdomen-pelvis CT. Prior to the data recording step, all hospitals had a mandatory one-hour training on the best practices in recording the relevant data elements. The recorded data elements included patient age, weight, protocol name, scanner information, acquisition parameters, and radiation dose descriptors including phase-specific CT dose index volume (CTDIvol in mGy) and dose length product (DLP in mGy.cm). We estimated the median and interquartile range of body-region specific CTDIvol and DLP and compared data across sites and countries using the Kruskal-Wallis H Test for non-normal distribution, analysis of variance. RESULTS: A total of 1061 patients (mean age 50 ± 19 years) were included in the study. 16 % of CT exams had no stated clinical indications for CT examinations of the head (32/343, 9 %), chest (50/281, 18 %), abdomen-pelvis (67/243, 28 %), and/or chest-abdomen-pelvis CT (24/194, 12 %). Most hospitals used multiphase CT protocols for abdomen-pelvis (9/11 hospitals) and chest CT (10/12 hospitals), regardless of clinical indications. Total median DLP values for head (953 mGy.cm), chest (405 mGy.cm), and abdomen-pelvis (1195 mGy.cm) CT were above the UK, German, and American College of Radiology Diagnostic Reference Levels (DRLs). CONCLUSIONS: Concerning variations in CT practices and protocols across several hospitals in Africa were demonstrated, emphasizing the need for better protocol optimization to improve patient safety.


Assuntos
Agências Internacionais , Doses de Radiação , Tomografia Computadorizada por Raios X , Humanos , África , Pessoa de Meia-Idade , Masculino , Feminino , Adulto , Energia Nuclear , Idoso
3.
Clin Chem Lab Med ; 62(10): 1928-1937, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39044459

RESUMO

The Health Technology Assessment (HTA) Working Group of the Emerging Technology Division of International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) aims to develop a methodological approach for producing structured HTA information for laboratory medicine technologies. This approach seeks to support decision-making processes at the country, regional, and/or hospital levels regarding the introduction of specific technologies. The focus of this model will primarily be on defining assessment elements within the domains of 'organizational aspects' and 'costs and economic evaluations', potentially differentiated by the type of diagnostic technology (e.g., genetic tests, molecular tests). To achieve this project's goal, a literature review and examination of websites of international HTA agencies have been conducted. The research aims to identify multidisciplinary methodological approaches used to assess laboratory diagnostic technologies and to pinpoint the domains and assessment elements utilized. We found 7 methodological articles describing methodological approaches adopted to assess laboratory diagnostic technologies. Among the HTA organizations considered, 23 reports were found, of which 7 were produced by the European Network of HTA (EUnetHTA), 4 by the National Institute for Health and Care Excellence Diagnostic Assessment Program (NICE DAP), and 12 by other HTA agencies. The EUnetHTA reports were rapid collaborative assessments covering various domains, while the NICE DAP reports focused on diagnostic guidances, including descriptions of technologies, clinical need and practice, diagnostic tests, accuracy, effectiveness, and cost-effectiveness. Finally, a survey targeting laboratory professionals will be conducted to introduce assessment elements, differentiated by the type of diagnostic technology, primarily for organizational and economic domains.


Assuntos
Agências Internacionais , Avaliação da Tecnologia Biomédica , Humanos , Técnicas de Laboratório Clínico , Laboratórios Clínicos
4.
Occup Environ Med ; 81(7): 366-372, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39033030

RESUMO

OBJECTIVES: To summarise the rationale, workflow and recommendations for the conduct of exposure assessment critiques in key human studies evaluated for International Agency for Research on Cancer (IARC) Monographs on the Identification of Carcinogenic Hazards. METHODS: Approaches to evaluating exposure assessment quality in human cancer and mechanistic studies were reviewed according to the precepts outlined in the IARC Monographs Preamble, using two agents as case studies. Exposure assessment 'domains', that is, salient aspects of exposure assessment for the agent under evaluation, were selected for review across the key human studies. RESULTS: The case studies of night shift work (volume 124) and 1,1,1-trichloroethane (volume 130) used a common approach, tailored to the agents' specific exposure scenarios, to evaluate exposure assessment quality. Based on the experiences of IARC Working Groups to date, the implementation of exposure assessment critique requires the need for agent-specific knowledge, consideration of the validity of time-varying exposure metrics related to duration and intensity, and transparent, concise reviews that prioritise the most important strengths and limitations of exposure assessment methods used in human studies. CONCLUSIONS: Exposure assessment has not historically been a fully appreciated component for evaluating the quality of epidemiological studies in cancer hazard identification. Exposure assessment critique in key human cancer and mechanistic studies is now an integral part of IARC Monographs evaluations and its conduct will continue to evolve as new agents are evaluated. The approaches identified here should be considered as a potential framework by others when evaluating the exposure assessment component of epidemiological studies for systematic reviews.


Assuntos
Carcinógenos , Exposição Ocupacional , Humanos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Carcinógenos/toxicidade , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Medição de Risco/métodos , Jornada de Trabalho em Turnos/efeitos adversos , Agências Internacionais
5.
J Radiol Prot ; 44(3)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39019049

RESUMO

This paper presents a proposed revision of the International Atomic Energy Agency transport regulations, related to theA1andA2limit values used to determine the radioactive transport classification. Based on the 'Qsystem', a novel methodology was introduced to deriveQAandQBvalues related to scenarios involving external exposure from a distant source. These values are key parameters that respectively represent the total effective dose and total equivalent dose to the skin, from all primary and secondary particles contributing to radiation exposure. The International Working Group (WGA1/A2) is established and associated with the TRANSSC Technical Expert Group on Radiation Protection. A review of theA1andA2values is performed in response to identified limitations within the existingQsystem. The followed approach is based on Monte Carlo simulations that enabled the development of transfer functions aimed at reducing computational time and increasing the flexibility of dose evaluations for any radionuclide with known particle emission spectra. This method allows updating theQAandQBvalues to account for future data evolutions (decay data, fluence-to-dose conversion coefficients) and standardizing the calculation of regulation limits across all referenced radionuclides and scenarios related to external exposure. The transfer functions are established using three Monte Carlo simulation codes-FLUKA, Geant4, and MCNP-and address the previous limitations of the 'Qsystem', reflecting the latest International Commission for Radiation Protection recommendations and improvements in calculation techniques. The results of the WG show consistent agreement across the codes, with minor discrepancies observed at low primary energies due to statistical uncertainties and different handling of stopping power for electrons/positrons in the codes. This revised approach aligns with current standards and recommendations, ensuring that the radiological consequences of transport accidents are acceptable for the newA1andA2limits from a radiological protection perspective.


Assuntos
Método de Monte Carlo , Proteção Radiológica , Proteção Radiológica/normas , Humanos , Doses de Radiação , Meios de Transporte , Agências Internacionais , Monitoramento de Radiação/métodos , Simulação por Computador
6.
J Radiol Prot ; 44(3)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38991515

RESUMO

In 2018, the International Commission on Radiological Protection (ICRP) released Publication 138, which highlights the ethical values foundational to the system of radiological protection. Additional work, both within and beyond the ICRP, has proposed or recommended ethical values associated with applications of the system in different areas, perhaps most notably in medical, veterinary, and environmental radiological protection. There are also existing ethical frameworks not specifically related to radiological protection that are nonetheless relevant to its practice; for example, the Beauchamp and Childress principles of biomedical ethics are of particular significance when it comes to medical uses of radiation and radioactivity. At first glance, it may seem as if there are unique or isolated sets of ethical values that need to be applied depending on the circumstance. Yet while each area of application will indeed have its own unique aspects and associated value judgements, there are consistent and complementary relationships between these ethical values. This paper reviews the work of the ICRP related to ethics, including brief historical context, and highlights the similarities and differences between sets of ethical values with emphasis on medical, veterinary, and environmental applications of radiological protection.


Assuntos
Agências Internacionais , Proteção Radiológica , Humanos , Agências Internacionais/ética
7.
Phys Med ; 124: 103392, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38862325

RESUMO

The International Commission on Radiological Protection (ICRP), recently expressed concern that "a shortage of investment in training, education, research, and infrastructure seen in many sectors and countries may compromise society's ability to properly manage radiation risks" and in 2022 announced the "Vancouver call for action to strengthen expertise in radiological protection worldwide". As representatives of organisations in formal relations with ICRP, we decided to promote this position paper to declare and emphasise that strengthening the expertise in radiological protection is a collective priority for all of us.


Assuntos
Agências Internacionais , Proteção Radiológica , Humanos
8.
Med Phys ; 51(8): 5632-5644, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38700987

RESUMO

BACKGROUND: The TRS­483, an IAEA/AAPM International Code of Practice on dosimetry of small static photon fields, underwent testing via an IAEA coordinated research project (CRP). Alongside small field output factors (OFs) measurements using active dosimeters by CRP participants, the IAEA Dosimetry Laboratory received a mandate to formulate a remote small field dosimetry audit method using its passive dosimetry systems. PURPOSE: This work aimed to develop a small field dosimetry audit methodology employing radiophotoluminescent dosimeters (RPLDs) and radiochromic films. The methodology was subsequently evaluated through a multicenter pilot study with CRP participants. METHODS: The developments included designing and manufacturing a dosimeter holder set and the characterization of an RPLD system for measurements in small photon fields using the new holder. The audit included verification of small field OFs and lateral beam profiles for small fields. At first, treatment planning system (TPS) calculated OFs were checked against a reference data set that was available for conventional linacs. Second, calculated OFs were verified through the RPLD measurement of point doses in a machine-specific reference field, 4 cm × 4 cm, 2 cm × 2 cm, and 1 cm × 1 cm, corresponding size circular fields or nearest achievable field sizes. Lastly, profile checks in in-plane and cross-plane directions were done for the two smallest fields by comparing film measurements with TPS calculations at 20%, 50%, and 80% isodose levels. RESULTS: RPLD correction factors for small field measurements were approximately unity. However, they influenced the dose determination's overall uncertainty in small fields, estimated at 2.30% (k = 1 level). Considering the previous experience in auditing reference beam output following the TRS-398 Code of Practice, the acceptance limit of 5% for the ratio of the dose determined by RPLD to the dose calculated by TPS, DRPLD/DTPS, was considered adequate. The multicenter pilot study included 15 participants from 14 countries (39 beams). Consistent with the previous findings, the results of the OF check against the reference data confirmed that TPSs tend to overestimate OFs for the smallest fields included in this exercise. All except three RPLD measurement results were within the acceptance limit, and the spread of results increased for smaller field sizes. The differences between the film measured and TPS calculated dose profiles were within 3 mm for most of the beams checked; deviated results revealed problems with TPS commissioning and calibration of the treatment unit collimation systems. CONCLUSION: The newly developed small field dosimetry audit methodology proved effective and successfully complemented the CRP OF measurements by participants with RPLD audit results.


Assuntos
Radiometria , Radiometria/instrumentação , Agências Internacionais , Projetos Piloto , Humanos , Fótons , Planejamento da Radioterapia Assistida por Computador/métodos , Aceleradores de Partículas
12.
Int J Radiat Biol ; 100(9): 1382-1392, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38284800

RESUMO

PURPOSE: Task Group 121 - Effects of ionizing radiation exposure in offspring and next generations - is a task group under the Committee 1 of the International Commission on Radiological Protection (ICRP), approved by the Main Commission on 18th November 2021. The main goals of Task Group 121 are to (1) review and update the scientific literature of relevance to radiation-related effects in the offspring of parent(s) exposed to ionizing radiation in both human and non-human biota; (2) to assess preconceptional and intrauterine effects of radiation exposure and related morbidity and mortality; and, (3) to provide advice about the level of evidence and how to consider these preconceptional and postconceptional effects in the system of radiological protection for humans and non-human biota. METHODS: The Task Group is reviewing relevant literature since Publication 90 'Biological effects after prenatal irradiation (embryo and fetus)' (2003) and will include radiation-related effects on future generations in humans, animals, and plants. This review will be conducted to account for the health effects on offspring and subsequent generations in the current system of radiological protection. Radiation detriment calculation will also be reviewed. Finally, preliminary recommendations will be made to update the integration of health effects in offspring and next generations in the system of radiological protection. RESULTS: A Workshop, jointly organized by ICRP Task Group 121 and European Radiation Protection Research Platforms MELODI and ALLIANCE was held in Budapest, Hungary, from 31st May to 2nd June 2022. Participants discussed four important topics: (1) hereditary and epigenetic effects due to exposure of the germ cell line (preconceptional exposure), (2) effects arising from exposure of the embryo and fetus (intrauterine exposure), (3) transgenerational effects on biota, and (4) its potential impact on the system of radiological protection. CONCLUSIONS: Based on the discussions and presentations during the breakout sessions, newer publications, and gaps on the current scientific literature were identified. For instance, there are some ongoing systematic reviews and radiation epidemiology reviews of intrauterine effects. There are newer methods of Monte Carlo simulation for fetal dosimetry, and advances in radiation genetics, epigenetics, and radiobiology studies. While the current impact of hereditary effects on the global detriment was reported as small, the questions surrounding the effects of radiation exposure on offspring and the next generation are crucial, recurring, and with a major focus on exposed populations. This article summarizes the workshop discussions, presentations, and conclusions of each topic and introduces the special issue of the International Journal of Radiation Biology resulting from the discussions of the meeting.


Assuntos
Proteção Radiológica , Radiação Ionizante , Humanos , Animais , Feminino , Exposição à Radiação/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/etiologia , Gravidez , Agências Internacionais
13.
Diabetes Metab Res Rev ; 40(3): e3656, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37179482

RESUMO

AIMS: Diabetes-related foot disease is a major source of patient burden and societal costs. Investing in evidence-based international guidelines on diabetes-related foot disease is important to reduce this burden and costs, provided the guidelines are focused on outcomes important to key stakeholders and are evidence-based and properly implemented. MATERIALS AND METHODS: The International Working Group on the Diabetic Foot (IWGDF) has published and updated international guidelines since 1999. The 2023 updates were made using the Grading of Recommendations Assessment Development and Evaluation evidence-to-decision framework. This concerns formulating relevant clinical questions and important outcomes, conducting systematic reviews of the literature and meta-analyses where appropriate, completing summary of judgement tables, and writing recommendations that are specific, unambiguous and actionable, along with their transparent rationale. RESULTS: We herein describe the development of the 2023 IWGDF Guidelines on the prevention and management of diabetes-related foot disease, which consists of seven chapters, each prepared by a separate working group of international experts. These chapters provide guidelines related to diabetes-related foot disease on prevention; classification of diabetes-related foot ulcer, offloading, peripheral artery disease, infection, wound healing interventions, and active Charcot neuro-osteoarthropathy. Based on these seven guidelines, the IWGDF Editorial Board also produced a set of practical guidelines. Each guideline underwent extensive review by the members of the IWGDF Editorial Board as well as independent international experts in each field. CONCLUSIONS: We believe that the adoption and implementation of the 2023 IWGDF guidelines by healthcare providers, public health agencies, and policymakers will improve the prevention and management of diabetes-related foot disease, and subsequently reduce the worldwide patient and societal burden caused by this disease.


Assuntos
Pé Diabético , Doenças do Pé , Doença Arterial Periférica , Humanos , Pé Diabético/etiologia , Pé Diabético/prevenção & controle , Cicatrização , Agências Internacionais
14.
Diabetes Metab Res Rev ; 40(3): e3657, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37243927

RESUMO

Diabetes-related foot disease results in a major global burden for patients and the healthcare system. The International Working Group on the Diabetic Foot (IWGDF) has been producing evidence-based guidelines on the prevention and management of diabetes-related foot disease since 1999. In 2023, all IWGDF Guidelines have been updated based on systematic reviews of the literature and formulation of recommendations by multidisciplinary experts from all over the world. In addition, a new guideline on acute Charcot neuro-osteoarthropathy was created. In this document, the IWGDF Practical Guidelines, we describe the basic principles of prevention, classification and management of diabetes-related foot disease based on the seven IWGDF Guidelines. We also describe the organisational levels to successfully prevent and treat diabetes-related foot disease according to these principles and provide addenda to assist with foot screening. The information in these practical guidelines is aimed at the global community of healthcare professionals who are involved in the care of persons with diabetes. Many studies around the world support our belief that implementing these prevention and management principles is associated with a decrease in the frequency of diabetes-related lower-extremity amputations. The burden of foot disease and amputations is increasing at a rapid rate, and comparatively more so in middle to lower income countries. These guidelines also assist in defining standards of prevention and care in these countries. In conclusion, we hope that these updated practical guidelines continue to serve as a reference document to aid healthcare providers in reducing the global burden of diabetes-related foot disease.


Assuntos
Diabetes Mellitus , Pé Diabético , Doenças do Pé , Humanos , Pé Diabético/etiologia , Pé Diabético/prevenção & controle , Agências Internacionais , Amputação Cirúrgica , Diabetes Mellitus/prevenção & controle
16.
Toxicol Sci ; 198(1): 141-154, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38141214

RESUMO

Systematic review and evaluation of mechanistic evidence using the Key Characteristics approach was proposed by the International Agency for Research on Cancer (IARC) in 2012 and used by the IARC Monographs Working Groups since 2015. Key Characteristics are 10 features of agents known to cause cancer in humans. From 2015 to 2022, a total of 19 Monographs (73 agents combined) used Key Characteristics for cancer hazard classification. We hypothesized that a retrospective analysis of applications of the Key Characteristics approach to cancer hazard classification using heterogenous mechanistic data on diverse agents would be informative for systematic reviews in decision-making. We extracted information on the conclusions, data types, and the role mechanistic data played in the cancer hazard classification from each Monograph. Statistical analyses identified patterns in the use of Key Characteristics, as well as trends and correlations among Key Characteristics, data types, and ultimate decisions. Despite gaps in data for many agents and Key Characteristics, several significant results emerged. Mechanistic data from in vivo animal, in vitro animal, and in vitro human studies were most impactful in concluding that an agent could cause cancer via a Key Characteristic. To exclude the involvement of a Key Characteristic, data from large-scale systematic in vitro testing programs such as ToxCast, were most informative. Overall, increased availability of systemized data streams, such as human in vitro data, would provide the basis for more confident and informed conclusions about both positive and negative associations and inform expert judgments on cancer hazard.


Assuntos
Carcinógenos , Neoplasias , Humanos , Carcinógenos/toxicidade , Animais , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Testes de Carcinogenicidade , Medição de Risco , Agências Internacionais
19.
J Radiol Prot ; 43(4)2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37857271

RESUMO

The benefits of biomedical research involving humans are well recognised, along with the need for conformity to international standards of science and ethics. When human research involves radiation imaging procedures or radiotherapy, an extra level of expert review should be provided from the point of view of radiological protection. The relevant publication of the International Commission for Radiological Protection (ICRP) is now three decades old and is currently undergoing an update. This paper aims to provoke discussions on how the risks of radiation dose and the benefits of research should be assessed, using a case study of diagnostic radiology involving volunteers for whom there is no direct benefit. Further, the paper provides the current understanding of key concepts being considered for review and revision-such as the dose constraint and the novel research methods on the horizon, including radiation biology and epidemiology. The analysis revisits the perspectives described in the ICRP Publication 62, and considers the recent progress in both radiological protection ethics and medical research ethics.


Assuntos
Proteção Radiológica , Radiologia , Humanos , Proteção Radiológica/métodos , Ética em Pesquisa , Agências Internacionais
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