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The Looming Nuclear Medicine Crisis

Regulation destroys modern medical imaging.

By Will Offensicht  |  November 12, 2009

We've written about bureaucrats making it harder to find cancer cures by making it difficult to enroll people in studies of new cancer treatments and we've told how regulations are forcing certain types of heart disease research to be done in other countries.

Bureaucratic harm to public health knows many forms: our bureaucrats aren't always hyperactive.  Sometimes they're asleep at the switch instead.

Science News put "Unstable Imaging" on their Sept. 26, 2009, cover to highlight the upcoming shortage of radioactive isotopes which are used in medical imaging.  The story "Desperately Seeking Moly" reports:

Mo-99 is the feedstock for technetium-99m, the isotope used in 80 percent of diagnostic nuclear medicine.  Roughly every three days, half of the Mo-99 will decay into TC-99m (the m stands for metastable). Every six hours, half of that decays into the long-lived TC-99 (not useful in medicine) which glacially decays into ruthenium.

This high-tech gibberish is saying that technetium-99m, which is used for more than 60,000 medical diagnostic procedures every weekday, doesn't last very long.  Every six hours, half of it decays into another material which isn't useful.

Tech-99m comes from the decay of Mo-99, but that doesn't last very long either.  Hospitals need weekly deliveries of Mo-99 to maintain their diagnostic schedules.

Unfortunately, a 52-year old nuclear reactor in Canada makes about 1/3 of the world's Mo-99 supply and a 47-year-old reactor in the Netherlands makes another third.  The Canadian reactor was shut down last May to fix a small leak.  Unfortunately, other corrosion problems were found during the repairs.  Officials are saying that the reactor won't start up again until well after the first of the year, and there are whispers that it's so old and so corroded that it may not be possible to start it up at all.

The reactor in the Netherlands shut down for routine maintenance for a month this summer.  With 2/3 of the production capacity offline and all the available material decaying fast, supplies of Mo-99 fell and medical diagnosis suffered greatly.  The Dutch reactor will have to be shut down for at least six months starting in March of 2010 for further maintenance.

There are no Mo-99 production facilities in the United States.

What the Shortage Means

Roughly half of the world's Tc-99m supply is used in monitoring blood flow into heart muscle after stress tests.  The patient exercises enough to get the heart rate up, then they inject radioactive material into the blood stream and track the movement of the radioactive particles.  This shows whether the blood vessels which supply the heart are working properly.  Treating such conditions before they become critical saves many lives.

There's an older procedure which uses thallium-201.  Thallium images are not as clear, doctors have forgotten how to read them, and they expose patients to much larger radiation doses, but the old way is better than no way.

About 16% of the technetium-99m is used to look for bone cancer. There is a substitute test which uses sodium-fluoride.  This test has been approved by the FDA but Medicare won't cover it because they believe that technetium-99m is more effective.  That may be true, but the fact that tech-99m is unavailable makes its superiority moot.  A number of medical centers have petitioned Medicare to cover the only available alternative, but Medicare doesn't plan to make an announcement until March.

Without these tests, patients will die unnecessarily. How will supplies be allocated during periods of shortage?  Will important government officials get priority when supplies are scarce?

How Did We Get Here?

This crisis has been coming for a long time.  It's no surprise that ancient nuclear reactors would need unexpected maintenance.  The question is, why wasn't another source brought online before now?

The problem is that American government regulations make building any sort of nuclear facility immensely time-consuming, costly, and cumbersome.  What's worse, this reactor will make substances which are used in medical care.  Add the FDA's slothful bureaucracy to the leisurely Byzantine processes of the Atomic Energy Commission and you're looking at years of somnolence before you'd see any Mo-99.

Even on an urgent basis, a new facility would take 4 to 10 years to build, license, and put into operation.  It doesn't seem that we can count on the existing reactors to work that long, so the government is looking into alternatives.

Mo-99 is made by bombarding nearly-pure, weapons-grade uranium with neutrons.  Some of the uranium turns into Mo-99 which is then extracted from the remaining uranium.  One shortcut would be to irradiate targets in the US and ship them to Canada where the Mo-99 could be extracted.

The Canadian extraction facilities are designed to work with targets from anywhere.  Using the Canadian extraction plant would avoid the FDA having to license a new extraction facility which "can take years."

Relatively few people are happy about shipping weapons-grade uranium around.  Any American plant would have to follow a new federal policy which limits the purity of targets they're permitted to bombard.  Instead of using 95% uranium as the Canadians do, they can use only 20% pure uranium targets.

This multiplies the number of targets needed by a factor of five.  It also makes it much more expensive to separate out the Mo-99 because there's five times as much uninteresting material mixed in with it.

There's been a great deal of discussion, but little action.  There's no plan for ensuring supplies of Mo-99.  There are still a great many regulatory and licensing obstacles that have to be overcome and nobody besides a few doctors seems to be particularly concerned about the years and years of regulatory delay we're facing.

To sum up: we have a serious, life-threatening problem that's been known for many years yet nothing much has happened.

The media are pointing out that the government's plans for making flu vaccine available aren't working well either - there are vaccine shortages everywhere.  Given their abysmal track record with well-understood medical problems, do we really want to give government yet more authority over medicine?