Is the likely benefit of a PSMA-PET scan higher than the radiation cost of the scans? I did a PSMA-PET scan in 2016, a regular CT-Scan in 2017 and 2019, and an Axumin scan in January 2021. The PSMA PET showed very small, suspected cancer in the aortic lymph node and a similar result in the Axumin scan. My PSA during those two scans was 38 and 22 respectively. I was not taking ADT at the time of those two scans. I was castration sensitive at the time of all those scans. I am now castration resistant and psa six weeks ago was .33 (up from .14&.20 in August).
I don't mind doing the PSMA-PET scan again if it is of value. Doctors seem to think it can be helpful but I am skeptical because those same doctors didn't use the information/findings of the last two ultra-sensitive scans, to do any kind of treatment. They said that the suspected areas of the cancer were in a sensitive location, which made spot radiation to risky. So why would the scans be helpful now?, and wouldn't a PSA of ~.33-.70 make it unlikely that they will see anything of significance that is actionable with radiation, especially considering that the last two Ult sen. scans were done when my PSA was 38 and 22 (whole numbers)?
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I’m in Canada and do not have this scan available to me: I have been told I can drive to the states as I am close to the border. $3,000 for the scan but the PSA must be over 2 to guarantee the 95% accuracy
That being said maybe the accuracy level is still very high . That I do not know
The positive predictive value of the scan is still very high all the way down to PSA of 0.5, or even as low as 0.20. Meaning the avid sites it finds are most likely cancer. But not so good at excluding mets still unseen. But a positive scan is very useful information to have!
I have it scheduled for Wednesday but I could postpone it and wait for PSA to get to a higher level but that seems unwise. I have not started 2nd line AR yet. Was thinking of getting this scan then I can start Nubeqa and provenge. I don't really think the scan will help with radiation options because following the previous scans, they said the suspected area of cancer was too sensitive to target due to proximity to my aorta, being in the aortic lymph node. Thus, by waiting, I'll let the cancer spread and not be able to target the original source anyway. The VA doctor said the UCLA radiologist is a higher level than others but then I ask if they want to see my previous scans and they say that they want a new scan. Whadda you think?
I'll try to fill that out this weekend. My treatments so far are: IMRT and brachytherapy for initial treatments. They failed and PSA started rising rapidly a couple months after the treatments. Since then, just intermittent ADT.
I think the Walter Reed radiologist, who was totally inexperienced on brachy, put too much radiation in one area of the prostate, which caused the radiation to blow out into my body, thus allowing the cancer to escape as well. I felt something for about three days, which Ive never felt before. It was right after that when the psa started to rise rapidly. I can't prove this, but I did see the seed array on the brachy procedure scans, and that why I think this is a plausible theory.
The detection rate of Pylarify PET/CT with PSA <0.5 is around 45%. If they find metastases or progression of the cancer they could decide to change treatment. If there are less than 5 mets they may decide to irradiate the mets and see what happens.
I became castration resistant and when 2 mets were detected , the MO and the RO decided to irradiate both. This resulted in a stable PSA for 6 months so far. Before this treatment the PSADT was 2 months,
Good data Tango. Also great news about you doing well. I suppose I’ll do the scan. Are you still taking adt? Did you use the Pylarify to identify those spots? What was your psa when you did the scans?
My PSA was 4 when the mets were diagnosed. We were chasing the mets with Pylarify PET/CTs since the PSA was 0.4.
The actual cancer has a low PSMA expression (max SUV was 7).
Since I had previous Lu 177 PSMA treatment, we speculate the mets have to get to a volume large enough to be detected since each cell may be expressing little PSMA. The lymph nodes grew from 0.5 to 1.1 cm before the mets were detected.
It is judgement call from the radiologists and ROs to decide an enlarged node is cancerous. In general they wait until the node is 15 mm or larger and there is clear evidence of size progression.
With PSMA PET/CTs, if the nodes are PSMA positive, there is cancer independently from the size of the node.
My nodes were PSMA negative until they got to be 10-12 mm. In about 5 months they jump from sub centimeter nodes to larger nodes and become PSMA positive.
In a PSMA PET/CT , the detection depend on the machine and the node has to irradiate enough gamma radiation to be pickup by the machine. If the cells have a low PSMA expression more cells are needed to produce enough radiation to be seen by the machine.
Hey Tango, I am India as I read your text. I stand on the aggressive side so as my PSA climbed from .57 to 1.14 we scanned (PSMA). It seems somewhere in the 9's is where they will consider introduction of Lu-177. I have 6 mets down from 20+ two years ago. All meet Suv minimums for therapy. Early detection is my key which will be different for others in that I am chemo naive and still willing to make the trip to Delhi to get the juice. Dr. Sen showed me the bone mets and as she pointed out and was obvious to me they were really tiny. We will repurpose on Monday and I will be back Thanksgiving Day. It is hard to call but looking to reduce this stuff for a bit longer than the 24 months I got last time. Once the numbers start to come in I will post. Looking forward to climbing back in my Husky and flying...Blue Skies ....Sky King and Penny (woof)
Thanks Tango ....feel great , going to knock this down a bit and get home to Penny(woof) and get in the cockpit....! Again I will post my results after my second infusion in a few months , until then one can always message me....Blue Skies
And you are a Nuclear Medicine Physician ? or is it really be determined by your blood work.....or MCi you recieve.....your statement is certainly not current trend of reintroducing the med, but thank you....Blue Skies
That 6 number is a SOC number and not a real life number. Your blood work is the determining factor. For instance 1200 MCi over 6 infusions was SOC now we are seeing patients blood work go to normal after a couple of years. This is not external beam radiation . The nuclear medicine doctor fine tunes what fits the patient in MCi and doses. I understand one relying on what is told but it may not actually be a scientific answer.....take care , Happy Thanksgiving, I will be on Virgin Atlantic while you eat the bird......
Yes but you can get it here now. If you can wait fine. I do not need it at this point. the great thing is it only spins off 1 uncontrollable molecule opposed to 4 with straight AC 225....you see I have the privilege of being friends with Dr. Sen and she is kind enough to explain all of therapies to me.
Here now I mean India...so I had the option but do I need over kill. She felt not and I agreed.. This will sufficient for me to kick the can and not have additional side effects.Stage 1 is a long way from possible approval . Drug company can shut it down any time. Again if you have time go with your dream .......BS which means Blue Skies ....I think👍
The long term side effects (toxicity) will show up in 8 to 10 years. If you have a life expectancy longer than 8 years Lutetium and Actinium treatment are not recommended.
Dr Sen told me she does not have the J591 ligand in India yet. She uses the small molecule ligands, not monoclonal antibody. It is different. Lu-J591 is available now in Perth. And Ac-J591 trial enrolling at Cornell Weill that Smurtaw linked.
And BTW, you are correct about dosing limits being individualized based on bone marrow function. With the small molecule radioligand such as Pluvicto much of the administered radiation dose is excreted in the urine very rapidly. Down the drain so to speak. Blue Skies to you sir. Paul
J591 being the monoclonal antibody that isn't absorbed by the salivary glands and kidneys right. Like a ligand is.And excluded from your system by a different set of organs, including gall bladder, pancreas, perhaps thru bile duct correct?
J591 is still a ligand in that it binds to PSMA on cells and carries a Lu177 isotope. There can still be some salivary gland effects, but very mild as lower doses are needed. Does not get excreted in the urine so no kidney toxicity. It is instead excreted in the bile and out the stool as you said. Circulates longer due to stronger binding to PSMA so can treat very small sites of cancer. But also has stronger effects on bone marrow suppression which are temporary but must be watched.
Uptake of PSMA-ligands in normal tissues is dependent on tumor load in patients with prostate cancerFlorian C. Gaertner, Khalil Halabi, [...], and Markus Essler
The hope is that there will be none left to be detected. However, non-PSMA expressing cancer clones may persist and grow, eventually detectable by other existing scans such as FDG-PET, Axumen, as well as the usual bone scans, CT, MRI.
It was very difficult for me to get the FDG PET scan, bone/ CT are less sensitive and I am not sure if I could get Axumen here? They don't order MRI, it is to slow they say, takes long time.
Definitely something to consider if someone is low volume and could get SBRT MRI Linac.
Small molecule Lu 177 PSMA and Ac 225 are toxic to the salivary glands, and the proximal tubules of the kidneys which express PSMA. Large anti body ligands has been reported to have little effects in the salivary glands and the kidneys.
It is true that small volume cancer may be problematic to treat with small molecule ligands with Lu 177 PSMA or Ac 225 because of salivary glands and kidneys tubules damage.
The antibody ligands can be used with small volume metastatic cancer but they will affect the bone marrow. Depending on the dose of radiation the bone marrow eventually will recover.
Lu 177 PSMA treatment could be and it has been rechallenged with a new set of variable number of treatments. It depends on PSMA expression, renal and bone marrow functions.
I would like to know more about these possibilities (ways). If you want you can sand me a private message about them.
I may don't do it straight but at least I could think about and consider them.
I am a slow moving person, like to think about possibilities. Sometimes I overthinking. I am doing things when I feel comfortable but I am open for all possibilities.
You also have my email address if you prefer that ruther than a pm here. It is up to you. I am not in a big hurry to act but would like to consider everything possible.
You mean before they were identified as PSMA avid prostate cancer mets.
Probably they have been seen growing on the scans. CT? Or MRI?
I have something on my lung seen by the CT scan first and also by the FDG PET scan but we believe it is not a prostate cancer as it is not PSMA avid yet.
Some other member.here is having a similar situation. His lung spot turned PSMA avid.(i am not sure if the size changed or not).
I consulted with 3 MOs and 2 ROs, My case was presented to the tumor meeting at the local cancer center,. All these people advised to do SBRT if oligometastatic even when having mCRPC.Dr Eiber at the Technical University of Munich, refused to do Lu 177 PSMA because there were only 2 mets.
Clinical example of Pylarify PSMA PET-CT sensitivity and PSA level. Recent new enhancing 0.4 x 0.9 cm nodule left prostate bed on prostate MRI six years after RARP. PSA level at time of scan was 0.115 & 0.113.
Is there a difference in PSMA PET-CT sensitivity between lymph node and local spread and PSA levels, ie need higher PSA levels for local spread as opposed to lymph node metastasis?
Ok I will throw in on that one but I'm having wine in New Delhi...Not sure psa would mean much since it has been told to me it is the biology of the tumor..I think Tall Allen would give you some clarity....but since I am here , I have never had a PSA over 13 yet high tumor loads. Again this is wine and a key board though I speak without a forked tongue...Blue Skies
I believe all Diagnostic testing is helpful... And may contribute to treatment decisions as well. The question of whether or not to allow the cancer to progress in order to get a better picture is controversial...
Question is, what changes if the scan finds something, whether it is consistent with earlier or other tests, or finds something new. Is there value with new information? Will it change the direction of therapy? The PSMA is still the most Sensitive even if it is only 45% efficient down to >4mm @ 0.05ng. and increases as PSA does (for most Patients). But at 2.0ng, you might as well use any scan... Because the only advantage then is seeing the smaller lesions.
I asked my MO the very question... And his answer was yes, it was worth doing the PSMA asap, and if it didn't reveal what was suspect in causing my PSA activity, we could do it again later. My PSA was <0.5ng at the time and I did it anyways, wasn't waiting. And three suspicious locations were detected, low SUV, but I've always been low PSA producer along with PSMA. This may be the criteria he used as well to determine there being no difference now or later as my previous 2 PSMA scans over the last few years also had low avidity. But we found 3 spots this time and are going ahead with treating them.
It's difficult to really "get" an answer from online, as everyone's cancer is their own, as is their situation. But it does help to share experiences. So I'm not attesting to validating anything as far as efficacy of the scan, you may decide to do it and not get anything in return for your efforts. But what if you did?... This is the conundrum as we all don't know, until we do it.
I'll end this with the seemingly consistent data involved in studies that early intervention typically prescribes the best results from treatment. So why then would we wait until the disease progresses just to do a test?
Will some things maybe be missed? Yes, of course, but with StgIV PCa, the hope of finding everything is already a foregone conclusion. Get the cancer when it's waking up, smack it hard and knock it back down, or wait until after it's already stretched it's arms and is loosened up, ready for the fight!?!? Lol
I just finished today the 5th SBRT radiation of my prostate.
I booked an appointment with the RO when my PSA jumped to 1.2.
I had a PSMA PET/CT scan when my PSA was 1.25.
I started SBRT with MRI Linac at PSA 1.4.
It was worth waiting as the PSMA PET scan only showed SUV max value 14 of the prostate and all my Mets resolved.
We believe that the prostate was 95% full with CRPC, therefore worth SBRT it.
At PSA 1.4 I didn't have mets on the 68ga PSMA PET/CT nor on the FDG PET scan, nor on a nuclear medicine bone scan. Therefore I decided to get rid of the CRPC in my prostate.
It was worth waiting to PSA 1.4 and above as I assumed they the rise of the PSA was associated with the grow of the cancer in my prostate.
And at value i didn't have any visible mets on any scan.
I feel comfortable with my desission to wait.
I would not feel comfortable to rush with the local radiation.
Sad that nothing could be done last time because of location of tumors...I had this debate with my RO...is there is a difference between PSMA and PSA...meaning, if you have large tumors will they will still have their PSMA still show up on a scan even though your PSA is suppressed momentarily by use of ADT? I spoke to Dr Calaise at UCLA when I did my scan Jan20 and he said yes the tumor would show up even though I was on ADT which suppressed my PSA...the two are not the same. This is what I understood. So if a patient had high PSA at one point, then suppresses his PSA via ADT, then should there be tumors they would still have PSMA targets to latch onto. This is what I understand...TNX
I was doing the "ADT and ME" study with my numerous bone mets for professor Emmett.
I underwent 4 x 68 GA-PSMA PET scans 2 weeks apart from my first Degarelix injection to study the PSMA expression change function of the change of the PSA.
(They took my PSA every time when I had a pet scan.)
Every cancer is different, so we get tend to get a few opinions from highly reputable cancer centers when we are unsure of what direction to take. My husband had psma and choline scans with psa well below 1.0. When we found something, we irradiated or cryo ablated. While it is a bit like whack a mole, my husband’s metastatic cancer remains localized in pelvis area, and his quality of life is excellent. In the pst 5 years, he’s had a total of only 18 months of ADT, which is super important to him. Two of the years he’s had no evidence of disease while being off all treatment.
The above to say that by working with your team, you can decide on the plan best for you. I’d just say make sure you get scanned at a place where they do many of them-the interpretation is quite important obviously. My husband’s psa for scans that showed Mets have ranged from 0 (a week later 0.1), 0.47, 0.16, and 1.6. He has Gleason 9 adenocarcinoma and had a prostatectomy. His Mets have shown up in the pelvic bone (doc at Mayo and clinic related that we treated early and Mets were very superficial), and 2 lymph nodes in the pelvis.
This disease is so frustrating because of all the variances and differing opinions even among top experts. We are encouraged with the new options even since my husband was diagnosed, so we keep “kicking the can down the road”. Hopefully the emerging treatments will continue to offer hope. Best of luck!!!
i had psma in sept 21 with psa 1.5 that showed areas of progression from prior axumin scan. Repeat last month (oct 22). With psa 0.3 showed continued progression wih additional skeletal lesions So my answer is yes. The scan lets us see what the cancee is doing. PSA may not. This lead to change in med regimen So the oncologist found it useful in treatment decision making But every case is different
might be interesting to some of you. The original paper is from Oct 2017 but some of the citations at the bottom are from late 2022.
Note: I had found, and thought I had bookmarked, what I thought was a very good discussion of how PSMA-PET scans can be misinterpreted depending on the experience and expertise of the reading radiologist. I did a quick search to find the article but wasn't successful. If you are interested I recommend that you do a better search than I did.
It was explained to me that the real purpose of the combination of the PSMA-PET scan with a CT scan is to identify the specific tissue/organ where positive areas are found. In my case multiple lymph nodes. Of course, a CT scan is also used to find tumors in soft tissues.
I'm not in a good situation other than if I try some desperation therapies. I don't have any known mutations. They won't do radiation on the lymph nodes since there are quite a few of them and they are scattered up and down my left side, except in the ilia area where they are on all sides. I can't do ADT, which is the SOC for me since I am hormone sensitive. I can opt for chemo but that would be way early and not really SOC for where I am at right now. That may change after my new bone and CT scans are done in three weeks. At that point the recommendation for radiation to specific bothersome hot spots may be done. Or chemo with more evidence to its necessity. As we all know, chemo is really just a stop-gap measure with horrible side effects (at least for more than some).
At some point I may get shoe-horned in to trying a PSMA irradiation therapy but there aren't any trials even in the planning stage for my situation (that I can find or that my MO can find). I am in what is called watchful waiting. Personally, I don't think a miracle is on the horizon either. I can't find any nomographs for predicting how fast my PCa will go but it "normally" would be faster than the ones you can find for men who are on the "normal" SOC with hormone therapies. At the moment I am just watching and waiting. I think I will post the findings of my scans next month.
There is a chance, I guess, my MO will pull some kind of rabbit out of his hat. I don't even have a time range for what may come so I am just "getting my affairs in order" on a proactive basis. One side of that is assuming that I am around for one or two or several years more. The other side would mean no more Thanksgiving next year. I am not really feeling morbid right now. My wife is freaking out. I'm just grateful I have been able to do a few cool things in my life. Many others have died much younger than me from any number of types of things. I never expected to live this long. Truly. So it's all borrowed time in my book.
How old are you now? Did you post a question on this site, asking everyone's opinion on what treatment you can do now? I agree with your philosophy. It's hard to get overly excited about life when we have this cancer inside us. Helping others in need and being close to Jesus and God is most important to me. Heaven is more important to me than skydiving and rocky mountain climbing.
I am 72. The one thing I am concerned about the most, with everything else a distant second, is what this will mean to my wife, emotionally and in dealing with all the things that, in our marriage, I have been doing for both of us. Whether it is the wrong stereotype or not, I have been doing most of the heavy lifting on making some decisions and taking on some chores. E.g. I am more technical, do better with how to get from A to B driving, and just being there as a loving companion and mutual helper.
She has already taken on a lot of the physical chores that have become harder for me, like raking leaves, getting groceries, most of the cooking now, etc. Some things I do just to share all the little details of day to day life, like paying bills, reading maps, etc. She is far more socially minded than I am so I lean on her for much of the social planning and supporting friends. I am very grateful for all of it. I enjoy doing most all of what I do do. And I am very grateful that she has been doing a lot of what I could do, and for those things that I don't do as well as she does. This is what keeps me up at night. Not dying per se.
This forum has been very useful since there are a huge variety of problems and potential solutions that I haven't been aware of or just don't know from personal experience. I have learned a lot. And I have seen the other struggles that we all have to varying degrees. This is hard work for all. I am. not happy we are all faced with this but it helps me understand more of how others try to deal with it all. We are not alone when we read and contribute to the forum.
I just hope that the small contributions I have tried to make have been helpful and certainly not harmful. One of the things we all should understand is that each person, and each disease progress is different. What works for one may not work for me or for others. Some of what I see here seems to be completely wrong or misguided about which it may actually be me that suffers from this.
I almost went into the medical field and many times I have thought that I should have. So I built my education towards being qualified to doing that, either in research or in treating others. My traditional bad memory, even when young, would have made this a bad idea at least on the treatment side. We all should be grateful for the professional medical, emotional, and solution-finding helpers out there trying to find and administer therapies. I say this even though I don't believe that we always get good advice or therapy from each of those providers. They are all individuals like we are and subject to the same issues as we do.
Medicine is quite often just voodoo certified by certificates on walls. The problem for all of us is to try and separate the wheat from the chaff. In many cases we trust in those who give us the most hope in our own minds even when the treatments may actually be very much more harmful than helpful. It really helps that there are some on this forum who I trust more than I do some of the researchers and providers. There are many of those who are extremely competent and compassionate. I have changed MO's a few times when I lost confidence in their care. I get PO'd when I don't see progress in the development of therapies that might help me, such as, trials seeking answers that would definitely be useful to me.
Above all, I consider QOL to be the overriding most important goal of them all. I understand that developments in medicine are, by their very nature, incremental. And for many issues, Mother Nature may actually be smarter and more stubborn than we are.
I always write more about anthills that are important to me are than my long-winded submissions deserve. Thank you all for bearing with me. And thanks for all who find true fault with some of the things I say at times. Like you all, I am passionate about all this. It is personal. I am resolute in trying to understand and do what I can. Life isn't always very fair though. I wish everyone success in beating what they are fighting.
I agree with what you are saying. Thinks I’m life are usually very subtle and the truth isn’t always easy to find. You’re right. We need to be open minded enough to realize who is telling the truth, believe people’s individual experiences, understand the underlying conditions of men enrolled in clinical trial, factor in quality of life etc. Thanks for your insights and experiences. Remember to play sports and laugh more. Let others in your life, carry a heavier load than you. I violate this rule as well.
thanks for the info smurtaw. good data. what doctor/clinic helps with your BAT? or do you do it on your own? I can't keep track all the self-dosing BAT guys. Is the liquid biopsy you mention, the Foundation One testing, or something else?
You remarked you were concerned by radiation load from PSMA/CT. The radiation is from the CT side and very short-lived isotope markers. I had VMAT radiation totaling 60 grays to my prostate. I reckon this is the rough equivalent of 20000 CT scans. What I have come to realize is we need to balance several things that are age-accelerated and PCa treatment-accelerated. IE PCa treatment-evasion risk, bone loss risk, muscle loss risk, future cancers, heart disease, etc. My MO and RO assure me that future side effects are manageable, that progression to CRPC is not the end of the game. As for future cancers, not smoking and drinking on top of a prostate and heart healthy lifestyle and having good genes....
My PSA is very low, 0.17, and I’m getting a PSMA scan tomorrow. It was recommended by my PCa specialist, Dr. Sartor. I became castrate resistant about a year ago after being undetectable for about seven years. Dr. Sartor said that since I’ve been on ADT for close to nine years now it’s possible that I can have a low PSA cancer.
He said even with a PSA as low as mine he has seen patients with nothing showing up, some cancer showing up, or a lot showing up on a PSMA scan. He wants to be proactive and see what we’re dealing with - something I agree with and that’s been my approach since day one.
Once we know what we’re dealing with we’ll decide what action to take.
Ed, what exactly does Sartor mean by, "ADT for close to nine years now it’s possible that I can have a low PSA cancer." What is a low psa cancer? Does that mean that the cancer spreads without the PSA rising?
I still don't understand why he said that you have a low psa cancer. That is obvious that you have a low psa and cancer, but the cancer isn't a low psa cancer, if the psa keeps rising. Then it would eventually be a high psa cancer.
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Anyone left the US to get a PSMA PET scan?
To PET or not to PET
At what PSA will a PSMA PET scan be useful?
False Hope?
Axumin verses Bonescan
