I recently had a PSMA PET/CT and I asked a similar question. I was told that the PSMA shows that there is cancer, but it is not very detailed. That is why the MRI is used to get a detailed picture of the lesion locations.
In my case, my doctor started tracking my PSA a while ago when it was 2. In 2019 it rose to 4 and he did PSA and free PSA and told me that per the standards I had a 25% chance of having prostate cancer.
I had just rescued my 92 year old mother from the covid nursing home and did not want to get involved in some big project so I chose to wait and see.
The PSA got a bit worse and hit 10 early in 2022. I should mention that the scale for the PSA only and PSA+free seems to be different with PSA number being lower.
I went to a local urologist and saw the APRN. She seemed like she was pushing me right into an old fashioned 12 core grid biopsy. At that time, my friend who works for GE on MRI gave me a podcast with Dr. Busch in GA who is a proponent of the TULSA PRO procedure. Listening to that podcast made me aware to the overtreatment of prostate problems.
I switched to a urologist at a major teaching hospital that was running TULSA clinical trials. He agreed with me that I should have a multi-focal MRI to see if there was a reason to go further. The MRI showed two lesions, one likely to be clinically significant cancer.
I had a biopsy that blended the MRI with US imaging and targeted the suspicious areas and also did the 12 grid. That is said to have a detection rate around 97%.
I had only a couple cores positive and was declared grade group 2 (gleason 3+4). He sent the tissue out for a Decipher genomic test that looks for 22 mRNA biomarkers and it said I was in the low risk category.
Based on that we decided to watch and wait. He said 50% chance of needing a procedure in five years.
This summer I had another MRI and biopsy. There were a few more cores than the first time and the cells were worse. I was declared grade group 3 (gleason 4+3) and told that I need a procedure. I had the PSMA PET/CT to look for metastatic cells and to confirm that the cancer is localized to the prostate.
We met last week and decided that of the various treatment options the TULSA procedure met my criteria the best. My priorities were to stay alive and minimize side effects as well as avoid a long treatment like radiotherapy.
I am having my TULSA next week and will probably make a thread on my adventure once it is over.
For those who might be wondering trans-urethral ultrasound procedure is an incision less process where ultrasound emitters are threaded up the urethra and use heat to kill the cells in the target area. The process is done inside an MRI machine and aside from the margin mapping is completely under robot and computer control. It is a one day visit to the hospital.
This is from Profound Medical (PROF) and seems likely to become a popular for of treatment. If all goes well I will buy some more shares of PROF
P.S. My personal opinion is that people should monitor their PSA but be cautious to avoid over treatment. There are also some genomic tests coming out that could be done prior to biopsy or even MRI that might be better than PSA level.