Wide range of measures planned – politicians must take the lead(Vienna, February 2010) There must be no repetition in 2010 of the shortage in the supply of low-level radioactive isotopes which occurred in Europe in August 2008 and led to the cancellation of nuclear medicine procedures, some of which were urgently required. This was the demand made by the European Association of Nuclear Medicine (EANM).
To comply with this demand, it will be necessary, in addition to coordinating effectively the maintenance of the available reactors, to speed up plans for new reactor building or retrofitting of existing research reactors. It will also be required to make increased use of other radiopharmaceuticals which hitherto have not been used as frequently. “The aim is to ensure that nuclear medicine examination and therapy will be available to all patients throughout Europe,” explained EANM President Prof. Wolfram Knapp from Germany.
Using isotopes to make the spread of cancer visible
It is primarily the isotope molybdenum-99, from which technetium-99m is extracted, which is in short supply. Nuclear medicine physicians use technetium in four out of five applications with radioisotopes. They combine it with drugs, which are in most cases injected by syringe and which target specific organs of the body. When the technetium decays in these organs, the radiation is recorded by a special camera – the resulting image is known as a scintigram. Applications of this technique include detecting the spread of cancer or making visible perfused areas of damaged myocardium (heart muscle) in which a bypass operation may be performed. Around 70,000 examinations of this sort are carried out each day all over the world.
Because of its short half-life of six hours, technetium cannot be stored in clinics and practices. A generator therefore has to be used to extract technetium from molybdenum. Since molybdenum also decays within 67 hours, it is necessary to supply medical establishments with a new generator every week.
Only five reactors throughout the world
More than 90 per cent of all molybdenum-99 is produced in only five reactors throughout the world, namely in Chalk River (Canada), Petten (the Netherlands), Mol (Belgium), Saclay (France) and Pelindaba (South Africa). A prolonged reactor shutdown in Chalk River led to supply shortages in North America in 2007. In summer 2008 a shortage also occurred in Europe because all three European reactors were out of operation simultaneously. Since May 2009 the reactor in chalk River has been on an extended shutdown for repair. Over the next five to ten years there is a risk of a chronic undersupply because it is feared further interruptions in production may occur since all of the main reactors are over 40 years old, according to EANM President Knapp. Ways of dealing with the crisis have been sought in urgent discussions with various bodies including the Association of Imaging Producers & Equipment Suppliers (AIPES), the EU Health Security Committee (HSC) and the Nuclear Energy Agency of the OECD.
Creating new reactor capacities
Following discussions with the other bodies involved, the EANM proposes the following measures to help alleviate or solve the problem:
- Maintenance and repairs of the five reactors should be highly coordinated. For example, the reactor with the highest output in Europe, the High Flux Reactor (HFR) in the Netherlands, ceased production for six months on 19 February 2010. A planned maintenance in France was therefore postponed until June 2010.
- New reactor capacities must be created to ensure a long-term supply of isotopes. A proposed new research reactor named PALLAS should replace the HFR in the Netherlands in 2016. In Germany the Technical University Munich intends to produce molybdenum-99 in their research reactor in Garching in the future; the necessary engineering work could begin in October 2010.
- Other radionuclides should play a greater role in diagnosis and therapy. Diseases of the thyroid can be investigated with I-123 (iodine), diseases of the myocardium with TI-201 (thallium). These alternatives, however, are associated with higher radiation exposure to patients and higher costs. Diseases of the skeletal system can be investigated with F-18 (fluorine) PET (positron emission tomography). The quality of these bone investigations with PET is excellent. Greater use of PET examinations should be possible because a substantial number of cyclotrons are available for the production of PET isotopes. However, PET isotopes cannot completely replace scintigraphy based on technetium-99m.
Guaranteeing nuclear medical examinations
Prof. Knapp considers that applying these measures should make it possible to meet the overriding goal of providing all patients with the nuclear medical examinations they require. The EANM President issued a reminder on behalf of the European nuclear medicine physicians that this is primarily a challenge which Europe as a whole must meet. Prof. Knapp: “This goal must be met by the responsible bodies irrespective of the profitability of isotope production.”