Hi all, one of our consults mentioned using material from husband"s bone biopsy material to assess PSMA, and said it could be done at his hospital as ours doesn't do it. Barry's MO agrees it would be helpful to check PSMA at this point.
QUESTION --- Would this give us the same information as a PSMA scan? If a scan is preferable (or even if isn't the choice) I'm curious which type of scan is the best idea?
No. Pet-PSMA scans, like the GA78 scan given at UCLA uses a radioactive material that is given thru an IV that attaches itself to parts of your body (like tumors) that are expressing PSMA, it’s a relatively accurate reading of where cancer is in your body, more so that standard bone and ct scans.
In favor of IHC test: it is quantitative and precise; it shows you cancer irrespective of whether it expresses PSMA; it also provides other histological info.
Downside of IHC test: it only tells you about the biopsied material. Best if multiple sites are biopsied.
In favor of PSMA PET: it is full body; there is some quantitave info because the uptake is higher in the most PSMA-avid regions
Downside of PSMA PET: it only shows cancer that expresses significant amounts of PSMA; can be high rates of false negatives on a per tumor basis (not on a per patient basis) - patient should also have an FDG PET scan.
In my personal experience no place is going to treat you with Lu 177 PSMA is you do not have a recent PSMA PET/CT (Ga 68 or 18 F DCFPyl). They only treat if they can see the cancer. Besides they need the PET/CT to determine how effective is the treatment.
If you have many treatments, such as chemo and second generation anti androgens and many metastases with high PSA, it could be useful to do a FDG PET/CT to determine how much cancer is not PSMA positive. It could help to decide if Lu 177 PSMA treatment is indicated.
As far as I am aware only the group of Dr. Hofman in Australia is doing both scans to decide if treatment is indicated. I believe the groups in Germany with the largest experience do not do both scans to decide if Lu 177 PSMA is indicated.
I was just speaking with my doctor who gave me Lu177 treatment last year.
My Psa is rising fast again but Psa is only 15, and Lu177 seemed to kill all the soft tissue mets I had, but there is some Pca activity in in bones, according to the last recent PsM Ga68 scan. The scan showed I have enough PsMa avidity to make Lu177 act well when I have some more of it.
But doc was worried that I may have Pca that does not generate PsMa expression, so I had an PET FDG scan which is a normal PET scan but with radioactive sugar used to find mets. The result of that showed I have no mets that would not respond to Lu177, so all my mets are expressing PsMa to attract the Ga68, so all my mets should attract doses of Lu177, which I will begin on 24th July, soon. The docs see no need to do any biopsy of my bones or of any soft tissues from where Pca is known to me, so it seems all can be known from PsMa Ga68 PET+CT scans, and the PET FDG scan. Had the FDG scan found mets which would not make an image in PsMa scan, and thus not respond to Lu177, then I may have needed to have DNA analysis for Brca1+2 genes, and if I was positive, and I think I am, because of family history, then docs would have put me onto PARP inhibitors, such as Olaparib.
Anyway, I am ready to proceed with more Lu177 and docs were able to get me some Veyonda from the makers for free on compassionate grounds, so my current position looks like I have a good chance of reducing my Pca soon and at least getting another year or two of high quality QOL.
I live in Canberra, in Australia, and I have only to travel 300km to get to Hospital in Sydney where Lu177 nuclear therapy is done.
The PsMa scan cost usd $490 and PET FDG scan cost usd $420, and our Medicare does not fund these, and I am not insured, but the purpose of my life's savings are to cover medical expenses, regardless of Medicare funding which has funded a big % of all my treatment.
Navigating the medical system is a nightmare for some folks, so I understand your difficulty and uncertainty, but its hard to know just what questions to ask of doctors, so you need the docs who are real happy so see you, and do the best for you, and whose knowledge and methods are right up with The Best.
I wish you all the best,
Patrick Turner.
I see little point in having histochemical analysis (of PSMA) of one PC metastasis. The point of a PSMA scan is to sensitively determine if and where mestatases (that express PSMA - frequently most of them) are present in the body. This allows different treatment regimes to be decided on, including, but not only, Lu177.
Post treatment post ADT time to PSMA test
Do not trust your first bone scan
Confused about which scan is more suitable
