How Toxic is PSMA Gallium scan and LU 717?

[TEBozo]

How much radiation? Compare to LU 177 treatment?

[tango65]

This article will give you an idea about Ga 68 PSMA

ncbi.nlm.nih.gov/pmc/articl...

[ragnar2020 in reply to tango65]

Hi Tango65,

I knew if I waited awhile before trying to comment to this question a wiser more informed follower would present the real answer. Thanks a lot. I’ve filed that study away to pull it out when the next guy asks the same question. This is what makes this forum so valuable - collective memory and stored knowledge - more valuable than many of us realize.

JPD

[BruceSF]

The main difference between LU-177 and GA-68 is that Lutetium emits highly energetic electrons, which damage the dna of the cells it attaches to. Gallium, on the other hand, emits positrons. Positrons do not do very much damage at all, because they almost immediately collide with an electron, which destroys the positron and causes the emission of two photons, which are detected by the PET scanner.

You don’t usually hear much about positrons because they are very rare in the universe - Gallium-68 produces them because it is unstable due to having too many protons relative to its neutrons, so one of its protons occasionally turns into a neutron and emits a positron and the gallium atom actually turns into a zinc atom (since zinc is right before gallium in the periodic table).

[MateoBeach in reply to BruceSF]

Nice summary of the topic Bruce. 👍👍

[BruceSF in reply to MateoBeach]

Thanks for reading, Paul, and thanks for sharing the info about J-591 Lu-177 for micro mets last month!

[MateoBeach]

Lutetium 717 must be a typo for 177. Not one of the isotopes for Lu. Toxicity of Lu 177 treatments such as Pluvicto is mainly renal, with some mostly short term salivary. Should have eGFR of close to 60 or above, then not a problem.

[MateoBeach in reply to MateoBeach]

en.m.wikipedia.org/wiki/Iso...