I'm in a similar situation. I was treated for PCa last summer, RT and HT, successfully with a rock bottom PSA after treatment, <0.01.
Just waiting for a PET CT scan to confirm whether I have another cancer or not.
Had a U/S scan for liver pain in Feb which found a 2" diameter growth on my right adrenal gland, on top of the kidney. It wasn't there 11 months ago on a previous scan.
CT scan found it wasn't the kind of growth I was hoping for, a benign adenoma and the density of the growth suggest it's a metastasis or other cancer. PCUK specialist nurses said it's unlikely to be related to PCa as the PSA would be higher.
Radiologist suggested A PET CT scan which will show if it's cancer.
Just heard this on Monday, so bit of a blow.
Trying to keep positive by thinking how lucky I am they found it.