Omission of Axillary Dissection Following Nodal Downstaging With Neoadjuvant Chemotherapy.

Importance: Data on oncological outcomes after omission of axillary lymph node dissection (ALND) in patients with breast cancer that downstages from node positive to negative with neoadjuvant chemotherapy are sparse. Additionally, the best axillary surgical staging technique in this scenario is unknown. Objective: To investigate oncological outcomes after sentinel lymph node biopsy (SLNB) with dual-tracer mapping or targeted axillary dissection (TAD), which combines SLNB with localization and retrieval of the clipped lymph node. Design, Setting, and Participants: In this multicenter retrospective cohort study that was conducted at 25 centers in 11 countries, 1144 patients with consecutive stage II to III biopsy-proven node-positive breast cancer were included between April 2013 and December 2020. The cumulative incidence rates of axillary, locoregional, and any invasive (locoregional or distant) recurrence were determined by competing risk analysis. Exposure: Omission of ALND after SLNB or TAD. Main Outcomes and Measures: The primary end points were the 3-year and 5-year rates of any axillary recurrence. Secondary end points included locoregional recurrence, any invasive (locoregional and distant) recurrence, and the number of lymph nodes removed. Results: A total of 1144 patients (median [IQR] age, 50 [41-59] years; 78 [6.8%] Asian, 105 [9.2%] Black, 102 [8.9%] Hispanic, and 816 [71.0%] White individuals; 666 SLNB [58.2%] and 478 TAD [41.8%]) were included. A total of 1060 patients (93%) had N1 disease, 619 (54%) had ERBB2 (formerly HER2)-positive illness, and 758 (66%) had a breast pathologic complete response. TAD patients were more likely to receive nodal radiation therapy (85% vs 78%; P = .01). The clipped node was successfully retrieved in 97% of TAD cases and 86% of SLNB cases (without localization). The mean (SD) number of sentinel lymph nodes retrieved was 3 (2) vs 4 (2) (P < .001), and the mean (SD) number of total lymph nodes removed was 3.95 (1.97) vs 4.44 (2.04) (P < .001) in the TAD and SLNB groups, respectively. The 5-year rates of any axillary, locoregional, and any invasive recurrence in the entire cohort were 1.0% (95% CI, 0.49%-2.0%), 2.7% (95% CI, 1.6%-4.1%), and 10% (95% CI, 8.3%-13%), respectively. The 3-year cumulative incidence of axillary recurrence did not differ between TAD and SLNB (0.5% vs 0.8%; P = .55). Conclusions and Relevance: The results of this cohort study showed that axillary recurrence was rare in this setting and was not significantly lower after TAD vs SLNB. These results support omission of ALND in this population.

Optimización de la protección en radiología y cardiología intervencionista pediatrica en América Latina y el Caribe (OPRIPALC) / Optimization of protection in pediatric interventional cardiology and radiology in Latin America and the Caribbean (OPRIPALC)

El objetivo del presente artículo ha sido describir el programa "Optimización de la Protección en Radiología Intervencionista Pediátrica en América Latina y el Caribe" (OPRIPALC) que nace el año 2018 como respuesta conjunta de la Organización Panamericana de la Salud y la Organización Mundial de la Salud, en cooperación con el Organismo Internacional de Energía Atómica, para colaborar con sus Estados miembros en asegurar que las exposiciones a la radiación de los pacientes pediátricos sean las mínimas necesarias durante los procedimientos intervencionistas. Actualmente, hay 18 centros de los siguientes 10 países que participan: Argentina, Brasil, Chile, Colombia, Costa Rica, Cuba, Ecuador, México, Perú y Uruguay. Para el desarrollo del programa se plantean una serie de objetivos, productos, actividades y resultados esperados. La puesta en marcha de la WEB de OPRIPALC ha significado un instrumento muy válido para seguir la información actualizada del programa. Un programa actualizado de formación en radioprotección para los profesionales implicados en el programa, se está realizando por medio de "webinars". Se deberá seguir actuando en la aplicación del programa de control de calidad básico para los equipos de rayos X participantes y validar los valores de los Niveles de Referencia para Diagnóstico (NRDs). Se propone formar un equipo de trabajo entre los Físicos Médicos y Tecnólogos Médicos participantes de OPRIPALC para implicarse en las pruebas de control básicas que todos los centros debieran realizar. Se han presentado algunos resultados iniciales de OPRIPALC en eventos científicos internacionales. Se está avanzando en proponer unos primeros valores sobre NRDs en procedimientos de intervencionismo cardiológico pediátrico por bandas de edad y peso. OPRIPALC es una de las pocas iniciativas de carácter regional para obtener valores de NRDs en procedimientos intervencionistas pediátricos. Se espera que tanto los valores de referencia como la metodología empleada en OPRIPALC, puedan ser utilizados en otras regiones del mundo.

The objective of this article has been to describe the program "Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean" (OPRIPALC) that was born in 2018 as a joint response of the Pan American Health Organization and the World Organization of the Health, in cooperation with the International Atomic Energy Agency, to collaborate with its member states in ensuring that radiation exposures of pediatric patients are the minimum necessary during interventional procedures. Currently, there are 18 centers from the following 10 countries participating: Argentina, Brazil, Chile, Colombia, Costa Rica, Cuba, Ecuador, Mexico, Peru and Uruguay. For the development of the program, a series of objectives, products, activities and expected results are proposed. The launch of the OPRIPALC WEBSITE has been a very valid instrument for following up-to-date information on the program. An updated training program in radiation protection for the professionals involved in the program is being carried out through webinars. It should continue acting in the application of the basic quality control program for the participating X-ray equipment and validate the values of the Diagnostic Reference Levels (DRLs). It is proposed to form a work team among the OPRIPALC participating medical physicists to get involved in the basic control tests that all centers should carry out. Some initial results of OPRIPALC have been presented at international scientific events. Progress is being made in proposing first values on DRLs in pediatric cardiac intervention procedures by age and weight bands. OPRIPALC is one of the few regional initiatives to obtain DRLs values in pediatric interventional procedures. It is expected that both the reference values and the methodology used in OPRIPALC can be used in other regions of the world.

The Inter-Agency Committee on Radiation Safety-30 years of international coordination of radiation protection and safety matters.

The Inter-Agency Committee on Radiation Safety (IACRS) was constituted in 1990, as a forum for collaboration and coordination between international bodies with regards to radiation safety. It consists today of representatives of eight intergovernmental member organizations (the European Commision, Food and Agriculture Organization, International Atomic Energy Agency (IAEA), International Labour Office, Organisation for Economic Co-operation and Development/ Nuclear Energy Agency (OECD/NEA), Pan American Health Organization, United Nations Scientific Committee on the Effects of Atomic Radiation and the World Health Organization) and five observer non-governmental organizations (International Commission on Radiological Protection, International Commission on Radiation Units & Measurements, International Electrotechnical Commission, International Radiation Protection Association and International Organization for Standardization). The IACRS provides a platform for interaction between these relevant international bodies to contribute to a common understanding of the scientific basis and legal framework for the application of the system of radiation protection, towards global harmonisation of radiation safety standards. The IACRS played a key role in the development of the International Basic Safety Standards (BSS) in 1996 and in its revision in 2014. Further, an IACRS specific Task Group-chaired by the IAEA-fosters the implementation of the BSS in a consistent and coherent manner in all Member States of the United Nations. The IACRS operates via a standing secretariat jointly provided by the IAEA and OECD/NEA and is chaired by one of its member organizations on a rotating basis for periods of about 18 months. This approach has proved to be effective and was the foundation for ensuring continuity of the work of the committee and at the same time allowing a rotating leadership for all member organizations. Currently, the IACRS is chaired by the WHO. The International Radiation Safety Framework under which the IACRS works is structured around four main areas: (a) science; (b) principles; (c) standards; and (d) practice. This paper presents briefly the mandates, roles and functions of the various international bodies that are relevant to the four above mentioned areas of work, discusses how these bodies coordinate their actions and complement each other to enhance radiation protection and safety worldwide and describes their contribution to the achievement of the Sustainable Development Goals. The paper also provides an overview of the main accomplishments of the IACRS since its inception 30 years ago, and an outlook on key challenges for its future activities.

Children, medical radiation and the environment: An important dialogue.

There are unique considerations in the medical care of children, which includes the use of medical imaging. Medical imaging is frequently necessary and is essential in diagnosis and management of children with illness and injury. Much of medical imaging requires ionizing radiation. While virtually all diagnostic imaging radiation is considered low-dose level, there is still a broad misperception about what modalities use ionizing radiation and how much radiation risk exists in the medical environment. A discussion of radiation exposure is especially relevant in children due to their increased vulnerability, including to radiation-induced cancer. Ionizing radiation is both naturally occurring and man-made, including medical sources that have been increasing over the past few decades and can vary in radiation dose both between different modalities and for similar examinations. Perspectives vary regarding cancer risk and levels of radiation resulting from diagnostic imaging, however most medical and scientific organization support the perspective that the risk of cancer at these levels is uncertain. It is important to have balanced and informed resources for the use of ionizing radiation in the care of children, and it is equally important to assure that the delivery of this content is appropriate to the audience to which it is intended. For these reasons, it is valuable to review the issues related to use of ionizing radiation in medical imaging in children.

The role of fathers in the postpartum period: experiences with skin to skin method / O papel do pai no período pós-parto: experiências com o método pele a pele / El papel del padre en el período del postparto: experiencias con el método piel a piel

OBJECTIVE: This study aimed at investigating the significance of the skin-to-skin contact method with fathers, looking at their own experiences with their newborns. METHODS: The information was collected through in-depth interviews with 14 fathers who had used the skin-to-skin contact method with their newborns, after a cesarean delivery. The technique utilized for data analysis was the qualitative method of content analysis. RESULTS: Four principal themes emerged from the data: the preparation for the skin-to-skin method, the experiences of the fathers, the father's role, and effects of the method on the baby. CONCLUSIONS: The investigations performed highlighted the importance of the involvement of health professionals in the use of this method, which leads to a series of positive results for the organization related to satisfaction. We conclude that the skin-to-skin method is a simple technique, recommended for positive results for fathers and their babies.

OBJETIVO: Este estudo tem como objetivo investigar o significado do método "pele a pele" com pais, olhando para as suas próprias experiências com seus recém-nascidos. MÉTODOS: A informação foi coletada a través de "entrevistas em profundidade" em 14 pais que tinham usado o método de "pele a pele", com seus recém-nascidos após um parto por cesariana. A técnica utilizada no análise dos dados foi o método qualitativo de "análise de conteúdo". RESULTADOS: Quatro temas principais emergiram a partir dos dados: a preparação para o método "pele a pele", as experiências dos pais, o papel do pai e os efeitos do método no bebê. CONCLUSÕES: As investigações feitas destacam a importância do envolvimento dos profissionais da saúde na utilização deste método, o qual leva a uma série de resultados positivos para a organização relacionados com a satisfação. Concluímos que o método de "pele a pele" é uma técnica simples e recomendada com resultados positivos também para os pais e os seus bebês.

OBJETIVO: En este estudio se tuvo como objetivo investigar el significado del método "piel a piel" con padres, mirando hacia sus propias experiencias con sus recién nacidos. MÉTODOS: La información fue recolectada por medio de "entrevistas en profundidad" realizada a 14 padres que habían usado el método de "piel a piel", con sus recién nacidos después de un parto por cesárea. La técnica utilizada en el análisis de los datos fue el método cualitativo de "análisis de contenido". RESULTADOS: Emergieron cuatro temas principales a partir de los datos: la preparación para el método "piel a piel", las experiencias de los padres, el papel del padre los efectos del método en el bebé. CONCLUSIONES: Las investigaciones realizadas destacan la importancia del involucramiento de los profesionales de la salud en la utilización de este método, lo cual lleva a una serie de resultados positivos para la organización relacionados con la satisfacción. Concluimos que el método de "piel a piel" es una técnica simple y recomendada con resultados positivos también para los padres y sus bebés.

WHO 1st consultation on the development of a global biodosimetry laboratories network for radiation emergencies (BioDoseNet).

The World Health Organization (WHO) held a consultation meeting at WHO Headquarters, Geneva, Switzerland, December 17-18, 2007, to develop the framework for a global biodosimetry network. The WHO network is envisioned to enable dose assessment using multiple methods [cytogenetics, electron paramagnetic resonance (EPR), radionuclide bioassays, etc.]; however, the initial discussion focused on the cytogenetic bioassay (i.e., metaphase-spread dicentric assay). Few regional cytogenetic biodosimetry networks have been established so far. The roles and resources available from United Nations (UN) agencies that provide international cooperation in biological dosimetry after radiological emergencies were reviewed. In addition, extensive reliance on the use of the relevant International Standards Organization (ISO) standards was emphasized. The results of a WHO survey of global cytogenetic biological dosimetry capability were reported, and while the survey indicates robust global capability, there was also a clear lack of global leadership and coordination. The expert group, which had a concentrated focus on cytogenetic biodosimetry, formulated the general scope and concept of operations for the development of a WHO global biodosimetry laboratory network for radiation emergencies (BioDoseNet). Follow-on meetings are planned to further develop technical details for this network.

[Telomeres and genomic damage repair. Their implication in human pathology]. / Telómeros y reparación de daño genómico. Su implicancia en patología humana.

Telomeres, functional complexes that protect eukaryotic chromosome ends, participate in the regulation of cell proliferation and could play a role in the stabilization of genomic regions in response to genotoxic stress. Their significance in human pathology becomes evident in several diseases sharing genomic instability as a common trait, in which alterations of the telomere metabolism have been demonstrated. Many of them are also associated with hypersensitivity to ionizing radiation and cancer susceptibility. Besides the specific proteins belonging to the telomeric complex, other proteins involved in the DNA repair machinery, such as ATM, BRCA1, BRCA2, PARP/tankyrase system, DNA-PK and RAD50-MRE11-NBS1 complexes, are closely related with the telomere. This suggests that the telomere sequesters DNA repair proteins for its own structure maintenance, which could also be released toward damaged sites in the genomic DNA. This communication describes essential aspects of telomere structure and function and their links with homologous recombination, non-homologous end-joining (NHEJ), V(D)J system and mismatch-repair (MMR). Several pathological conditions exhibiting alterations in some of these mechanisms are also considered. The cell response to ionizing radiation and its relationship with the telomeric metabolism is particularly taken into account as a model for studying genotoxicity.