[secult]

PET scan (You have to wait for civic applications of the newly discovered technologies for a while, but the "technology transfer" from CERN to practical applications has a few notable examples.)

[joelthelion]

PET doesn't use antimatter, at least it doesn't use it directly. It uses regular radioactive tracers.

[Romain_Winler]

PET stands for Positron Emission Tomography. The radioactive tracers emit positrons (antimatter), which then annihilate with electrons to produce the gamma rays that are detected. So it does use antimatter, just indirectly through the decay process.

[secult]

Indeed, it would be quite difficult to smuggle some antimatter to a tumor. I'm saying that research in this particular area eventually led to practical application, PET scans.