Canadian Innovators On Track To Solve Isotope Shortage
Development and Innovation The nuclear medicine field in Canada will face new challenges when production of the technetium-99m isotope — used around the world to diagnose ailments from cancer to heart disease — is slated to stop in 2016 at the National Research Universal Reactor in Chalk River, Ontario.
But researchers across the country have embraced this change as an opportunity to devise and develop replacement technologies, and are confident that their solutions will be equal to or even better than the technetium-99m from the Chalk River reactor.
In the late 2000s, the worldwide medical community was in the grips of an “isotope crisis” when two of the largest producers of technetium-99m (Tc-99m) were temporarily sidelined with technical problems. Tc-99m is the world’s most widely used isotope, employed millions of times per year to image, for example, heart disease after heart attacks.
One of the producers is the NRU reactor at Chalk River, which has typically been producing 40 to 50 percent (and up to 80 percent) of the world’s supply of the isotope molybdenum-99 (Mo-99), the precursor to Tc-99m. When the NRU stops production after 57 years of operation, it will effectively end the current supply of Tc-99m in Canada. That’s the bad news.
The good news is that Canadian innovators are finding solutions that will ensure that future isotope shortages are averted at home and abroad.
New cyclotron for medical imaging in Saskatchewan
Situated at the University of Saskatchewan, the Sylvia Fedoruk Canadian Centre for Nuclear Innovation is named for one of the nation’s nuclear medicine trailblazers. It will operate the province’s first medical cyclotron accelerator and radioisotope laboratory, now under construction. This machine will produce radioactive isotopes for use in imaging procedures, including diagnosing cancers. Construction of the cyclotron will be finished at the end of October and will start operating next year. It will be able to produce a variety of medical isotopes applicable to nuclear medicine, including an agent for PET-CT imaging at Saskatoon’s Royal University Hospital for the diagnosis of cancer and other diseases.
“TRIUMF and its partners are developing next-generation technology that will allow communities across Canada to produce locally sourced medical isotopes.”
“Our expectation is that researchers in Canada will soon develop alternatives to technetium-99m for medical imaging, and that these will work as well or even better,” says Centre Executive Director Neil Alexander.
New medical isotopes and imaging techniques can replace traditional Tc-99m procedures, but Tc-99m’s status as the world’s workhorse isotope remains. “There is really nothing that can replace it,” says Dr. Jean-Luc Urbain, President of the Canadian Association of Nuclear Medicine (CANM). “The world has realized that the NRU is going offline, and is looking for a replacement strategy.”
So the federal government has funded three initiatives to ensure a domestic supply of Tc-99m from alternative sources post 2016.
B.C. innovation to address shortage of isotopes
One initiative in B.C. is working hard to develop a non-reactor-based, made-in-Canada solution to produce Tc-99m. Researchers at TRIUMF lead this team; a national laboratory for particle and nuclear physics located in Vancouver. “For over 50 years, isotopes have been a mainstay of nuclear medicine,” said TRIUMF Director Dr. Jonathan A. Bagger. “At TRIUMF, we are using accelerators to produce known isotopes and to create new ones for use in diagnostics and therapeutics here and around the world.”
Across the country, hospitals and universities use a number of cyclotron accelerators. Regional infrastructure investments, such as the new cyclotron at the Fedoruk Centre, represent why Canada has one of the world’s most advanced cyclotron install-bases. Canada is thus uniquely positioned to pursue this alternative production route for Tc-99m.
“TRIUMF and its partners are developing next-generation technology that will allow communities across Canada to produce locally sourced medical isotopes, including Tc-99m,” said Dr. Bagger. “This will improve the security of Canada’s isotope supply and ensure a reliable source of isotopes for all Canadians.”
Cyclotron production of Tc-99m has several advantages over reactor-produced Tc-99m, including production without a nuclear reactor, without enriched uranium, and without long-lived radioactive waste. Other teams in Canada are pursuing similar projects with other production means, further demonstrating Canadian innovation in action. When it comes to Tc-99m, Canada continues to lead the way.