Trans-Atlantic Consensus on the Medical Management of Radiation Accident Victims
Authors: Sirohi Bhawna , Powles Raymond , Niederweiser Dietger , Coleman Norm , Chao Nelson J. , Bader Judith , Case Cullen , Chute John , Confer Dennis L. , Gourmelon Patrick , Gorin Norbert C , Ganser Arnold , Port Matthias , Meineke Viktor , Krawisz Robert , Weinstock David M , Wiley Albert , Fliedner Ted 
Published: April 2020

Hematologists will play an important role in the management of radiation accident victims. In 2005, an EBMT (European group for Blood and Marrow Transplantation) International Consensus Meeting defined a unified basis for the medical management of radiation accident victims (Gorin NC et al, Ann Hematol.2006;85(10):671–9). The core of this consensus was the 2001 “METREPOL” (Medical Treatment Protocols for Radiation Accident) clinical grading of irradiated victims, based on data from 800 victims in 70 previous accidents. The “METREPOL approach” to triage concentrates on the medical examination of the patient in order to assess the “severity of effect” and the “indicators of repair” of the 4 most important organ systems: hematopoietic, neurovascular, gastrointestinal and skin. A report of the medical preparedness was recently published by the US Radiation Injury Treatment Network (RITN) (Weinstock et al, Blood2008; 111(12):5440–5; Fliedner et al, Blood2008; 111(12):5757–8) and supplemented by the EBMT. In addition, the US Department of Health and Human Services REMM (Radiation Event Medical Management; http://remm.nlm.gov) web-based system allows for the continual up-date of medical management and provides information for medical personnel. A workshop including experts from both sides of the Atlantic was organised to take forward a consensus on management of radiation victims, including appropriateness and indications for hematopoietic stem cell transplantation (HSCT). What is achievable following a radiation event will be dictated by the size and scope of the event. It is not expected that hematologists will be involved in the primary triage of victims. Instead, the primary aims for medical management by hematologists include:

reducing short and long term morbidity using available supportive care and medical countermeasures, providing expertise to non-hematologists who may be called upon to manage victims with cytopenias, collecting clinical data and potentially biospecimens from radiation victims and 4) reassuring those who have not received significant doses of irradiation (i.e.”worried well”).

Also, the clinical triage would determine whether an autologous recovery of hemopoiesis is possible or not. If the hemopoiesis is irreversibly damaged, then reconstitution of hemopoiesis through HSCT may be the only possibility. All other cases are likely to restore hemopoiesis on their own but may require bridging of the pancytopenic phases. The consensus for the use of cytokines was that: G-CSF is to be commenced in all patients with peripheral blood absolute neutrophil count (ANC) of &lt;500/uL at any time-point. An estimate of dose based on the victim’s location at the time of the event (i.e., geographic dose reconstruction) may be available after some incidents;if exposure was estimated as &gt;300cGy or &gt;200cGy with combined injury, then G-CSF is to be commenced independent of ANC. As the supplies of G-CSF may be limited after a mass event, G-CSF should NOT be given to patients who do not meet these criteria. Evidence for the use of pegylated G-CSF does not favour its use if G-CSF is available. Erythropoiesis stimulating agents are not to be used routinely. Victims who require transfusions should receive irradiated, leukodepleted products, if possible. It is expected that only a small fraction of victims would be candidates for allogeneic HSCT. Indications, timing and guidance for considering an allogeneic HSCT will be presented. There was also discussion on the importance of harmonizing European and US medical education curriculum on medical response to catastrophic radiological incidents where it will be very important that medical specialists in many countries will need to work together in the response.