The scan frequency and type seems to vary quite a bit between Cancer Centers.

I had my first post-Tx PET/CT after 10 weeks and my second six months thereafter.

I was told I will now be getting a PET/CT scan annually each May, but that doesn't preclude an extra scan if they need one (but, not necessarily a PET/CT).

The PET/CT scans are comparative and they wanted the post-Tx in about ten weeks to compare it to the one they took before Tx and as the post-Tx baseline.

I imagine it is a similar approach at many Cancer Center