Current status of hematopoietic stem cell transplantation for acute radiation syndromes.

Many people believe that hematopoietic stem cell transplantation (HSCT) together with various hematopoietic factors may aid or rescue victims of acute radiation exposure. However, nearly all patients who have received current HSCT for severe bone marrow damage in the past died relatively shortly after transplantation, even when engraftment followed by autologous blood cell recovery was observed. The causes of death in such cases involved rapidly progressing insults to many non-hematopoietic tissues, such as lung and gut, potentially exacerbated by the conditioning regimen and immune dysfunction. We should recognize that at present avoiding high-dose radiation exposure is the only safe option.