Intended for healthcare professionals

Letters Shortage of medical isotopes

Global shortage of medical isotopes threatens nuclear medicine services

BMJ 2008; 337 doi: https://doi.org/10.1136/bmj.a1577 (Published 05 September 2008) Cite this as: BMJ 2008;337:a1577
  1. Alan Perkins, honorary secretary1,
  2. Andrew Hilson, past president1,
  3. John Hall, treasurer1
  1. 1British Nuclear Medicine Society, Regent House, London SE26 4QD
  1. alan.perkins{at}nottingham.ac.uk

    Nuclear medicine departments throughout the world are facing the prospect of a severe shortage of molybdenum-99 over the next few weeks.1 Molybdenum-99, a fission product of uranium-235, is usually delivered to hospitals on a weekly basis in the form of the molybdenum/technetium generator. This is used for the routine production of technetium-99m, the main radionuclide used for over 80% of routine diagnostic nuclear medicine investigations. The result will be a major disruption in the provision of nuclear medicine services in the United Kingdom and elsewhere.

    The president of the US Society of Nuclear Medicine, Robert Archer, has described this as a “perfect storm in isotope availability,” in which a series of unrelated events have combined with serious consequences.

    Europe’s three isotope production reactors are all currently shut down. Belgium’s Federal Agency for Nuclear Control (FANC) ordered the Fleurus facility to stop production on 26 August after an uncontrolled release of iodine-131 into the atmosphere estimated to be 45 GBq. The High Flux Reactor (HFR) at Petten in the Netherlands will be offline for at least three weeks because of a yet unresolved problem of gas bubbles in its cooling system, and both the BR2 reactor at Mol in Belgium and the Osiris reactor in France are down for scheduled maintenance and inspection and are not expected to restart for several weeks. According to the Brussels based Association of Imaging Producers and Equipment Suppliers (AIPES), European producers have only enough radioisotopes to last until 8 September.

    This all coincides with a shutdown of the National Research Universal (NRU) reactor operated by Atomic Energy of Canada at Chalk River because of an electrical storm (although this reactor does not regularly supply Europe). In addition, South Africa’s Safari-1 reactor has recently completed a scheduled outage and is just getting back on line. The only other reactor supplying medical isotopes is the OPAL reactor at the Australian Nuclear Science and Technology Organisation (ANSTO) in Australia, but this reactor would not have the potential to increase production significantly for the world market.

    The global commercial producers usually operate in competition, but at such times they will collaborate to ensure adequate medical supplies. A fundamental issue, however, is that these commercial reactors are largely around 40 years old. In November and December 2007 the Chalk River reactor that provides the entire supply of molybdenum to the United States was out of action for safety reasons. This was reported to have affected over 50 000 patient investigations in the United States. These events led to the Canadian government overruling the Canadian Nuclear Safety Commission and to the dismissal of the Commission’s president. The only large-scale attempt to increase the production of medical isotopes in recent years began in Canada in 1999. Design faults, ongoing legal disputes, and rising costs forced the project to be cancelled earlier this year. There has been little other global investment in new reactor facilities and unless this changes these problems are expected to continue.

    So far the current problems have resulted in UK hospitals receiving less than 50% of the expected activity and supplies will be further reduced before they are reinstated. Industry and service providers are scheduling the supplies against clinical priorities. Although the production of the therapeutic radioisotopes Y-90 (yttrium Y 90 ibritumomab tiuxetan) and Re-186 (Re-186 hydroxyethylidene diphosphonate) will be limited the investigations mainly affected are diagnostic. The most significant procedures will be myocardial perfusion imaging, bone scans, the investigation of renal function (renograms), and some intraoperative sentinel node detection procedures for breast cancer.

    For some procedures alternative radioisotopes can be used—for example, a limited amount of bone imaging could be undertaken at positron emission tomography and computed tomography centres with F-18, and myocardial perfusion imaging can sometimes be carried out using thallium-201. Unfortunately the technique with thallium-201 is not suitable for all patients. Many requests for myocardial perfusion imaging are for obese patients, who are often unsuitable cases for alternative stress echocardiography or thallium-201 and are potentially at higher risk of angiography.

    Many of these requests are non-urgent, and most patients will be best served by waiting until sufficient technetium supplies come back on stream. This does raise an issue with the current Department of Health waiting times. Under these circumstances the “six week target for diagnostic wait times” is unhelpful. Some NHS managers feel under great pressure to take steps to avoid “breaches” of the six week target and are inclined to suggest switches in bookings purely on the basis of waiting times. Such actions may distort clinical priorities and may result in suboptimal treatment for some patients.

    Other radioisotopes such as indium-111 and iodine-123 and F-18 for positron emission tomography and computed tomography are not affected. At the time of writing, the full impact of the current problems has not yet been realised. Even when all the reactors are powered up there will be a delay before the molybdenum production process will be fully reinstated. In the mean time, the nuclear medicine community will endeavour to use the available limited resources in the fairest interests of clinical need. For further information see www.bnms.org.uk

    Notes

    Cite this as: BMJ 2008;337:a1577

    Footnotes

    • On behalf of the Council of the British Nuclear Medicine Society

    • Competing interests: None declared.

    References