I also got caught out by lack of working Cholene PET scans in December and January. I was due to have a scan because my PSA of 57 was rather high for the cancer they could find, which is all in the prostate.
This got me reading around the subject and I discovered PSMA PET scans, but my NHS trust doesn't pay for those, so after waiting 2 months I offered to do it privately. My trust instead put me in for a full body MRI which happened at the end of February. I figured I may as well do that because if it finds something significant, no point having the PSMA scan (plus the extra risk from the radiation dose), but if it didn't find anything, then I might go ahead with the PSMA scan privately.
I got the full body MRI scan result this week, and it can find no spread outside the prostate. I wasn't sure how detailed it would be, but I'm blown away by the detail of the report. It's not quite full body - they don't cover knees or below, or arms below the shoulders, but everything else is covered. They've looked through the lymph nodes and all are normal except one adjacent to thyroid gland but it implies that's not cancer related. There's detailed commentary on brain, lungs, pleural, pericardium, liver, spleen, bowel, with a few observations mentioned, but not cancer related. I have a little lower spine pain when I wake in the mornings which the radiologist wouldn't have known about, but they identified some disc dehydration there. Found a nonaggressive sinus polyp I didn't know about. The thing that really blew me away was the report of asymmetric retroareolar soft tissue. Checking in my own diary entry 2 days before the scan, I have written that Tamoxifen has completely got rid of left breast bud, but not quite the right breast bud yet - they even spotted that!
My consultant didn't think it was worth having a PSMA scan after the full body MRI, as he thought it unlikely it would change his suggested treatment (External beam RT and high dose Brachytherapy, where he's assuming there could be some locally advanced spread which isn't going to show on a scan). I wasn't quite so sure, but I hadn't seen the MRI report at that point, which is much more detailed than I was guessing it would be. Still not completely decided, but probably coming down on the side of not doing the PSMA scan - can keep it in reserve if PSA doesn't come close to zero after the RT.
Would love to hear anyone else's view on PSMA scan or not at this stage.
By the way, I've been having great fun looking through the MRI scan images. You need special software to get the most out of them. The scan CD's come with Windows software, but being a Mac person, I downloaded OsiriX Lite which is a professional DICOM imaging tool which is available for free to look at your own scans (some features disabled in the free version but not ones you would need, and you have to upgrade it every time a new version is released). The scan is 10500 images and came on 13 CDs.