GG,
I would ring the radiology department . As you are likely to have an infusion injected in your arm the vaccine might have an effect on how the infusion works.
My husband has been having 3 monthly scans for the last year, ct and mri, and this question has come up in the fib groups I belong to. I think, from memory, you should wait 7 days after the vaccination, but I would double check with the radiology dept to be sure. Same phone number that is on your letter that you confirm your appointment.
If you were not having any other blood work done then there shouldn’t be a problem with a normal consultation appointment.