Low-dose radiotherapy for COVID-19 pneumonia and cancer: summary of a recent symposium and future perspectives.

The lessons learned from the Coronavirus Disease 2019 (COVID-19) pandemic are numerous. Low dose radiotherapy (LDRT) was used in the pre-antibiotic era as treatment for bacterially/virally associated pneumonia. Motivated in part by these historic clinical and radiobiological data, LDRT for treatment of COVID-19-associated pneumonia was proposed in early 2020. Although there is a large body of epidemiological and experimental data pointing to effects such as cancer at low doses, there is some evidence of beneficial health effects at low doses. It has been hypothesized that low dose radiation could be combined with immune checkpoint therapy to treat cancer. We shall review here some of these old radiobiological and epidemiological data, as well as the newer data on low dose radiation and stimulated immune response and other relevant emerging data. The paper includes a summary of several oral presentations given in a Symposium on "Low dose RT for COVID and other inflammatory diseases" as part of the 67th Annual Meeting of the Radiation Research Society, held virtually 3-6 October 2021.

Preparedness for a 'no-notice' mass-casualty incident: a nuclear detonation scenario.

PURPOSE: An effective response for a mass-casualty incident requires understanding the relevant basic science and physical impact; detailed preparedness among jurisdictions; and clear, sequential response planning, including formal operational exercises, logistics, interagency, and public-private coordination, rapid activation of resilience, and continual improvement from lessons learned and new knowledge. This ConRad 2021 meeting report describes steps for civilian medical and public health response planning for a nuclear detonation; the utility of this type of planning for broader application; and extension of this planning to the international community. CONCLUSION: A nuclear detonation requires a response within minutes to what will be a large-scale disaster complicated by radiation, including some elements that are similar to a broad range of incidents. The response could be further complicated if multiple incidents occur simultaneously. Required are detailed planning, preparedness and scripting for an immediate operational response, addressing clinical manifestations of evolving radiation illness, and flexibility to adapt to a rapidly changing situation. This need translates into the use of just-in-time information; effective, credible communication; situational awareness on a global scale; and a template upon which to apply capabilities in a multi-sector response. This effort is greatly facilitated using a 'playbook' approach, the basics of which are presented.

United States medical preparedness for nuclear and radiological emergencies.

With the end of the Cold War in 1991, U.S. Government (USG) investments in radiation science and medical preparedness were phased out; however, the events of 11 September, which involved a terroristic attack on American soil, led to the re-establishment of funding for both radiation preparedness and development of approaches to address injuries. Similar activities have also been instituted worldwide, as the global threat of a radiological or nuclear incident continues to be a concern. Much of the USG's efforts to plan for the unthinkable have centred on establishing clear lines of communication between agencies with responsibility for triage and medical response, and external stakeholders. There have also been strong connections made between those parts of the government that establish policies, fund research, oversee regulatory approval, and purchase and stockpile necessary medical supplies. Progress made in advancing preparedness has involved a number of subject matter meetings and tabletop exercises, publication of guidance documents, assessment of available resources, clear establishment of anticipated concepts of operation for multiple radiation and nuclear scenarios, and identification/mobilization of resources. From a scientific perspective, there were clear research gaps that needed to be addressed, which included the need to identify accurate biomarkers and design biodosimetry devices to triage large numbers of civilians, develop decorporation agents that are more amenable for mass casualty use, and advance candidate products to address injuries caused by radiation exposure and thereby improve survival. Central to all these activities was the development of several different animal constructs, since efficacy testing of these approaches requires extensive work in research models that accurately simulate what would be expected in humans. Recent experiences with COVID-19 have provided an opportunity to revisit aspects of radiation preparedness, and leverage those lessons learned to enhance readiness for a possible future radiation public health emergency.

Achieving flexible competence: bridging the investment dichotomy between infectious diseases and cancer.

Today's global health challenges in underserved communities include the growing burden of cancer and other non-communicable diseases (NCDs); infectious diseases (IDs) with epidemic and pandemic potential such as COVID-19; and health effects from catastrophic 'all hazards' disasters including natural, industrial or terrorist incidents. Healthcare disparities in low-income and middle-income countries and in some rural areas in developed countries make it a challenge to mitigate these health, socioeconomic and political consequences on our globalised society. As with IDs, cancer requires rapid intervention and its effective medical management and prevention encompasses the other major NCDs. Furthermore, the technology and clinical capability for cancer care enables management of NCDs and IDs. Global health initiatives that call for action to address IDs and cancer often focus on each problem separately, or consider cancer care only a downstream investment to primary care, missing opportunities to leverage investments that could support broader capacity-building. From our experience in health disparities, disaster preparedness, government policy and healthcare systems we have initiated an approach we call flex-competence which emphasises a systems approach from the outset of program building that integrates investment among IDs, cancer, NCDs and disaster preparedness to improve overall healthcare for the local community. This approach builds on trusted partnerships, multi-level strategies and a healthcare infrastructure providing surge capacities to more rapidly respond to and manage a wide range of changing public health threats.

Low-Dose Radiation Therapy (LDRT) for COVID-19: Benefits or Risks?

The limited impact of treatments for COVID-19 has stimulated several phase 1 clinical trials of whole-lung low-dose radiation therapy (LDRT; 0.3-1.5 Gy) that are now progressing to phase 2 randomized trials worldwide. This novel but unconventional use of radiation to treat COVID-19 prompted the National Cancer Institute, National Council on Radiation Protection and Measurements and National Institute of Allergy and Infectious Diseases to convene a workshop involving a diverse group of experts in radiation oncology, radiobiology, virology, immunology, radiation protection and public health policy. The workshop was held to discuss the mechanistic underpinnings, rationale, and preclinical and emerging clinical studies, and to develop a general framework for use in clinical studies. Without refuting or endorsing LDRT as a treatment for COVID-19, the purpose of the workshop and this review is to provide guidance to clinicians and researchers who plan to conduct preclinical and clinical studies, given the limited available evidence on its safety and efficacy.