Cosset Jean Marc
Departement d'Oncologie Radiotherapie, Institut Curie, 26 Rue d'Ulm, Paris, France.
Radiother Oncol. 2002 Apr;63(1):1-10. doi: 10.1016/s0167-8140(02)00059-2.
Considering the number of radioactive sources in use all over the world (both in industry and medicine) irradiation accidents are exceedingly rare, as demonstrated by the main databases registering such cases: UNSCEAR, IAEA, REAC/TS (Oak Ridge, USA), the German group in Ulm and the Paris Institut Curie. The precise causes of most accidents have been openly analyzed, allowing to reduce the risk of subsequent identical accidental exposures. In addition, a rapid retrospective overview shows that positive lessons could be drawn from such accidents: 1)Lessons for patient management: one should keep in mind that the first ever allogeneic bone marrow transplantations were performed in 1958, on scientists from Yugoslavia who had been severely irradiated in a nuclear Research laboratory. Apart from what was learned from such accidents for the management of severe aplasia, the treatment of superficial accidental exposures has also benefited radiotherapy patients in certain specific situations. 2) Lessons for technology: the efforts to improve safety in nuclear plants are well known; the (successful) efforts to reduce the once-elevated risks when changing the therapeutic Cobalt 60 sources are less well known. Today, most irradiation accidents (by far) are related to misuse or loss of radioactive sources from industrial radiography sets. However, here again, various technological improvements significantly reduced the risks. 3) Lessons for radiobiology: the need for more and more sophisticated biological dosimetry has led to studies allowing better understanding of the short- and long-term effects of radiation on human cells. Analyses of samples taken in areas which were heavily accidentally irradiated also helped to identify, in particular, the cardinal role of TGF beta and TNF alpha in the development of fibrosis and necrosis after irradiation. 4) Lessons for prevention of accidents in radiotherapy: only three large-scale accidents involving external radiotherapy have been registered in the last decade, but deciphering the cause(s) of such problems clearly participated in the setting of demanding Quality Assurance programmes and strict national and international recommendations. Such open circulation of the information about these (fortunately rare) accidents appears to be one of the ways to improve Quality Assurance in Radiotherapy.
