The continued shortage of medical isotopes could bring back more invasive and expensive imaging techniques in the diagnosis of patients, according to speakers during a press conference held by the Society of Nuclear Medicine (Reston, Virginia) during its annual meeting.
The press conference comes on the heels of Canada recently shutting down its Chalk River Reactor, which supplies almost a third of the world's isotope supplies.
Atomic Energy of Canada (AEC; Mississauga, Canada) said the reason for the closure is because a leak is located "at the base of the reactor vessel in a location where there is corrosion on the outside wall," and while the rate of leakage "remains stable" at about 5 kilograms an hour, the plant's management said it is examining its options for plugging the leak site.
The situation is dire, according to the society, and remains as "one of the most significant medical crises" in recent history.
Canada is one of five nations, including — France, Belgium, the Netherlands and South Africa — that directly supplies the isotope known as molybdenum-99 the most commonly used medical isotope. The chemical decays within 67 hours of production and is incredibly hard to stockpile.
Canadian officials have said that repairs to the reactor could take up to three months, if the reactor is salvageable at all. In addition, the Canadian government has made it plain that it would permanently close down the reactor in 2016.
On top of that, the Dutch reactor is scheduled to be closed for at least four weeks for scheduled maintenance work.
"One of the anxieties we have is that we don't know when this reactor is going to come back online," said SNM President Robert Atcher of the Chalk River reactor.
Most of the reactors were built with 40-years of use in mind. Unfortunately, according to Atcher, nearly all are at least 40.
"Having the Chalk River site closing is a double whammy . . . since it has excess capacity to serve as a back-up when one of the other sites [is] down," Atcher said.
Already, hospitals and patients are beginning to feel the affects of its absence.
An e-mail survey conducted by the SNM shows that 91% of the 375 participants of the poll said they had been directly impacted by the shortage of the isotope. Nearly 60% said that procedures had to be postponed, with another 31% saying that screenings had to be canceled.
"There have been no actual deaths yet, but tests have been delayed and so has treatment," said Michael Graham, president-elect of SNM. "The alternative is that we're going to have to look toward more invasive [diagnostics] tests."
Positron emission tomography (PET) scans will also be utilized more. The problem is that some of these tests aren't covered by Medicare and could put an undue expense and burden on the patient.
"The danger is that you use imaging techniques that are less sensitive and less accurate but are more costly and more invasive," Atcher said.
The supply of molybdenum-99 has appeared to be shaky for the past two years. AEC had shut down the reactor in 2007 due to leak problems, which was followed last year by a temporary shutdown of a reactor in the Netherlands. The Nuclear Research and Consultancy Group (NRG; Petten, the Netherlands), reported the shutdown of its High Flux Reactor because of the periodic presence of "a very small trace of gas bubbles" detected in the reactor's primary cooling system.
Covidien (Mansfield, Massachusetts), which has relied heavily on the Netherlands site for isotopes, hasn't been directly affected by the Ontario site's closing. But the company said that it was bracing for impact and in a letter to the FDA's website said that "there will be challenges meeting full market need."
Some hospitals have already started to ration out the use of isotopes.
According to Peter Conti, MD, a prolonged shortage could even threaten clinical trials for cancer drugs because patients might not be able to obtain scans on schedule, which could force them out. He added that physicians are now only doing some of the most urgent tests.
The industry is on the brink of taking a step backwards instead of a step forward. But without a solution or more isotope sites put into place, then innovation in the diagnostics field could come to a screeching halt.
"We need to have a stable supply of isotopes for the broad spectrum . . . if we're going to move the diagnostics and molecular field forward," Conti said.