ASN Report 2020

bone metastases, and radium-223 for prostate cancer with bone metastases. One can also treat inflammatory diseases of the joints using colloids marked with yttrium-90, erbium-169, or rhenium-186. Radioimmunotherapy can be used to treat certain lymphomas using yttrium-90 labelled antibodies. Lastly, many patients are treated without being hospitalised, mainly for iodine-131 treatments (other than cancer) and, to a lesser extent, for synoviortheses or palliative treatment of metastatic pains. 4.1.4 Research in nuclear medicine involving humans Nuclear medicine research conducted on humans has been particularly dynamic in the last few years, with the regular introduction of protocols involving new radionuclides and vectors. Research focusing on the use of new tracers is continuing as much in diagnostic imaging (fluorine-18-fluoroestradiol, development of peptides marked with gallium-68, cardiac applications of iodine-124, exploration of pulmonary ventilation by aerosols marked with gallium-68, etc.) as in therapy (development of new molecules marked with lutetium-177, molecules marked with copper-64, etc.). The use of new RPDs means that the radiation protection requirements associated with their use must be integrated as early as possible in the process. Indeed, given the activity levels involved, the characteristics of certain radionuclides and the preparations to produce, appropriate measures must be implemented with regard to operator exposure and environmental impact. To anticipate the impact of these developments in radiation protection, ASN has called upon the IRSN to examine the prospects of using new radionuclides that could be put onto the French market in the years to come. What is expected: a bibliographic study of the radionuclides showing promise for use in humans and those already used in Europe or elsewhere in the world; the clinical application prospects; the radiation Circular letter to medical centres on the management of patients treated with lutetium-177 Lutetium-177 ( 177 Lu) is indicated for the treatment of certain neuroendocrine tumours in the adult and is the subject of much clinical research in the treatment of prostate cancers. Given its therapeutic prospects and the arrival of new vector molecules, the number of patients that could receive this type of Internal Targeted Radiotherapy (ITR) could increase significantly in the years to come. This is why ASN has updated the licensing conditions, previously formalised in 2014, for the possession and use of lutetium–177 by the nuclear medicine departments. This reassessment of the ASN recommendations concerns the treatment of patients and the management of waste and effluents. It is based on two opinions of the Advisory Committee on Radiation Protection for Forensic and Medical Applications of Ionising Radiation (GPMED) published in 2017 and on the consultation with the stakeholders on this theme. The recommendations resulting from this work were distributed to the heads of nuclear medicine departments, directors of health care institutions, and public sewage systemmanagers by circular letter of 12 June 2020. Good hospitalisation practices for patients in rooms or premises allowing the collection of contaminated urine in tanks, for a sufficiently long period, are reiterated in this letter. During the time necessary for the construction of appropriate new facilities in the health care centres, treatment on an “out-patient” basis is nevertheless possible within the nuclear medicine department. This temporary arrangement is subject to special precautions and an assessment of the impact of the discharges, which must be less than 1 millisievert (mSv) for all the categories of workers in the sewage system sector. The circular letter also provides details on the management of liquid effluents contaminated by lutetium-177. ASN points out that the instructions given to the patient when discharged from hospital may be adapted individually, under the responsibility of the physician, while ensuring the radiological protection of the people in the patient’s close environment. Lastly, the professionals involved in the treatment of these patients, who do not normally work in a nuclear medicine department, must receive reinforced on-site training in the radiation protection measures. Specifications are provided for this purpose. TABLE 3 Main radionuclides used in diverse in vivo nuclear medicine explorations TYPE OF EXAMINATION RADIONUCLIDES USED Thyroidmetabolism Iodine-123, technetium-99m Myocardial perfusion Thallium-201, technetium-99m, rubidium-82 Lung perfusion Technetium-99m Lung ventilation Technetium-99m, krypton-81m Osteoarticular process Technetium-99m, fluorine-18 Renal exploration Technetium-99m Oncology – search for metastases Technetium-99m, fluorine-18, gallium-68 Neurology Technetium-99m, fluorine-18 ASN Report on the state of nuclear safety and radiation protection in France in 2020 225 07 – MEDICAL USES OF IONISING RADIATION 07