IMAGING (Scans) for Metastatic PCa.

[LearnAll]

Today, I completed 6 years since PCa diagnosis (Initial PSA was 860, ALP 191 and bone mets in dozens)

This forum did help me immensely in my early days of diagnosis. I will be grateful always.

Lets understand various scans one by one used for observing metastatic PCa.

(1) Tc99 Bone Scan: This is old and least accurate scan. Why ? Because the tracer Tc99 sticks to any irregular spot on bone whether Cancer or not.. So it can give overestimation of number and size of bone mets. Even a scar tissue or patch of inflammation can light up on this scan.

(2) CT Scan: Prostate cancer bone mets are Sclerotic type ,also known as Osteoblastic type...Meaning as cancer corrodes bone.. body goes into repair mode putting calcium patches on these damaged spots. CT scan basically shows these repaired patches which may or may not harbor cancer cells...Therefore ,CT scans are also not accurate as they depict cancerous as well as non cancerous ,sclerosed ,repaired spots both at the same time.

(3) MRI scans: These scans are better than the above two .... MRI can show Bone spots as well as Soft tissue (organ) spots. There are ways to indirectly conclude whether a spot is active ,alive and growing or it just lying there without growth. A skilled good radiologist can correctly read live and static mets on MRI . But it still is by an indirect way.

(4) PSMA PET/CT scans: For PCa , PSMA PET/CT scan can be considered KING of All scans. Why? Because these are the Only scans which can clearly identify live, active cancerous areas. PSMA is a membrane which is ONLY found on prostate cancer cells and the tracer ( Pylarify or Ga68) goes in and sticks to these PSMA membrane and lights the area only where the live cancer cells are . The tracer does not stick to any other irregular spots EXCEPT true cancerous spot. Thats why these scans are most accuarate. However, approximately 15% men may have Non PSMA type cancer spots. For them, another scan might become necessary.

Friends, the risk of overtreatment is as big as risk of undertreatment....and the most crucial step is correctly knowing location, size and extent of metastatic spots. Knowledge is power and an antidote to fear. Best of luck.

[Orange95]

Congratulations on 6 years! I hope you continue for very long time! Good health to you! Thank you for your post!

[Lettuce231]

I'm pleased for you, Learn All, keep at it 👍

[Majedsh]

Congratulations and God blessMay I ask if initial diagnosis showed cancer in near prostate lymph nodes or not?

[LearnAll in reply to Majedsh]

No scan ever showed prostate primary. Only thing in the beginning was a lesion in one seminal vesicle which soon disappeared. Don-t know why. May be I was rubbing Clioquinol cream on groin and drinking liquid Zinc based on Dr leslie Castello's research. Just a speculation. My story is just the story of purely bone mets (nothing else)

[GreenStreet]

Congrats on the 6 years. I wish you many more 👍💪🤞

[hopeful1956]

Congrats on 6 years. May you have many more years ahead.

[lcfcpolo]

Thanks for this. In the UK I was not offered MRI or PSMA. Congratulations on your 6 years.

[cigafred]

"This forum did help me immensely in my early days of diagnosis." Yes, and your postings have helped me too, including this nice summary.

[dhccpa in reply to cigafred]

Amen

[lookingforamiracle]

Thank you, Learn All. And congrats on 6. Good to see in the forum again.

[j-o-h-n]

You keep Learning and we'll keep Yearning... .

Give "em' Hell,,,,

Good Luck, Good Health and Good Humor.

j-o-h-n

[Jazzman2023]

Congratulations on 6 years, and thanks for the excellent primer ! When you state 'another scan may become necessary' for the 15% that have non-PSMA type cancer spots...which type of 'another scan' are you referring to ? I'm in that low PSA producing P.C. 15% club...thanks !!

[StayingOptimistic in reply to Jazzman2023]

FDG I think.

[LearnAll in reply to Jazzman2023]

Prostate Cancer cells live on FATTY ACIDS mainly and on Animal protein to some extent. Saturated fatty acids of animal origin are their most favored food. FDG scan measures Glucose Metabolism and therefore is never needed in case of PCa Because the glucose is used by PCa only in extremely terminal stage. Think of Warburg effect ! A rough measure of extent of Warburg effect (glycolysis) is by blood LDH (lactate Dehydrogenase ) level. For non PSMA type cancer cells, Choline (Axumin) scan may be better because this scan measures protein metabolism. , But FDG scan is never a right choice for prostate cancer.

As a general rule, Low PSA producing cancer cells are more aggressive than high PSA producing cells. Producing PSA is their main day job ...so if they are churning out a lot of PSA it means they are not too distorted. PSA indicates extent of disease.. PSA does not tell degree of aggressiveness of cancer cells. The clues to aggressive Cancer are (1) Very low PSA with lot s of mets (2) Bulky lymph nodes (3) High LDH (4) High Chromogranin A (5) Visceral (organ) mets. (5) short lasting effect of ADT and high PSA Nadir.

[Jazzman2023 in reply to LearnAll]

Thanks for the explanation, I will ask my M.O. about a Choline (Axumin) scan). I have a low PSA producing form of high risk Gleason 4+5 PC...So this may be appropriate for me......Thanks again !!

[dhccpa]

Good to hear from you. We don't hear from you often enough these days. I hope you're doing great!

A few comments/questions.

1. My RO says MRIs don't do well in chest area; too much bone to see lungs, etc. True or not?

2. You said 15% of men don't express PSMA. Or is it that 15% of prostate cancer cells don't express PSMA, and varies by individual?

3. What do you see as the limitations of PSMA PETs? Do they detect older bone metastases? Say 4+ years? All metastases, bone, lymph, and organs? Other issues?

4. What in your view is the best scan to detect non-PSMA PCa cells? Is there any way that what is being detected are non-PSMA cells with the same certainty as the PSMA PET detects PSMA cells?

Thanks. I've found it challenging to get answers to those questions, and they are very relevant to me nowadays.

[ron_bucher in reply to dhccpa]

My onco docs order Axumin scan when in doubt about negative PSMA scan.

[ron_bucher in reply to dhccpa]

#2 - my onco says the lack of PSMA expression is specific to the patient, not to cells within a patient

[dhccpa in reply to ron_bucher]

Very possible, although I've heard that patients can have both. I don't know.

My RO is skeptical that the Axumin (I've had four, and one PSMA, very contradictory results) is complementary to the PSMA. I've seen conflicting opinions.

[dhccpa in reply to ron_bucher]

For what it's worth I Google the question and here is how their in-house AI answered. Hope it comes through.

google.com/search?q=is+lack...

[ron_bucher in reply to dhccpa]

As a former computer science major and programmer, I don’t trust AI for answers to medical questions. AI might be useful for generating questions, but buyer beware on its answers

AI aside, I suspect there are exceptions to every rule in pCa.

[LearnAll in reply to dhccpa]

dhccpa. PSMA scan not showing any mets is a very good news as 85% PCa are PSMA avid. Also, with longer treatment duration, more PSMA is produced making these old mets more visible. Choline Axumin can be alternative. But I would go and get biomarkers such as LDH, Chromogranin A etc to find out how aggressive the cells are. If you are interested in details, I have a post a few years ago about aggressive variants and how to recognize them...Search my old postings. Answer2: Varies by individual Answer 3: All kinds of PSMA avid mets are seen on PSMA PET...Bone, Lymph node or Organ, Answer 4: May be Choline Axumin....But not with the same certainty.

[dhccpa in reply to LearnAll]

Thanks. We're going to run an FDG PET early fall (I've never had one of those), followed by a PSMA PET scan after the first of the year (2nd one) and see how they compare. I've had four Axumins stretching from January 2020 to January 2024. Hopefully all that will shed some light. Of course, it would nice if my first PSM from 7/2024 was correct about no metastases, since I've now had full prostate and pelvic radiation.

Regarding LDH, I've had resistance from my docs about the need. However, I see where Ulta Labs has it for $19.95, so I may just run the basic one. My Alkaline Phosphotase has been excellent (below low end of normal) for five years now.

[GHTomato]

grateful for the information. Knowledge is power. We must all share information.

[podsart]

My Dr suggested taking an MRI and bone scan. I told him why the MRI if my PSA is too low for an MRI to detect. The bone scan is very sensitive but can’t give an accurate actionable location and , as pointed out above, gives possible false positive Pca sites.

So is the bone scan worth it?

[LearnAll in reply to podsart]

Treatment based on bone scan can lead to overtreatment as bone scan is NOT specific to Cancer cells.

[SeosamhM]

As usual - great post, LearnAll!

[Kaliber]

congrats on hitting the 6 year mark brother. Just passed 6 myself 4 months ago. I hope you hang in there 18 more years or until the “ fix “ comes. Rotflol. My psa at DX was 1400-1600 , not that far from yours.

Interestingly, none of my 4 different oncologist ( over time ) has been interested in how many Mets I have. My original oncologist told me my met load was so high that another scan wouldn’t be necessary or forthcoming, there was no point. Of course I’ve had several specialized scans, lower back, knees and brain in the six years since then , my last one mentions light progression in the size of a hand full of lumbar / big bone Mets, Still it’s never been mentioned to me. I just read about it in the comments/ notes .

It’s interesting how seemingly all of us have so much variation in our circumstances, tho it kinda seems like we could be lumped into a few generalized categories. Mets have damaged my knees and feet ( joints ) beyond repair / normal use , I’ve got a whole pa’ve of tiny mets peppered all around my skull, especially my mandible, and nasal passages. Mets in every bone joint in my body, 6 years of xtandi has singed my white matter a little too Rotflol. It kinda seems right , as you say, knowledge of size, where etc of your Mets esp activity would be invaluable …. Mostly the few scans I’ve had relate to specific Mets where I feel acute pain, this so they can document my pain management, for the “ hot “ locations. All this solely with the thought of keeping me comfortable until …… Well you know.

I did have some excitement a while back when I started sleeping 16-18 or more hours a day. My oncologist gave me transdermal estrogen patches which awakened me back up again. …. Kinda lol.

Well buddy sounds like we have a lot in common in our perspectives and circumstances …. Pretty kewl . So many guys here receive very much different treatment.

We’ll both hang in there together buddy, love ya

❤️❤️❤️

[dhccpa in reply to Kaliber]

That estrogen is still benefitting you. I wish I could interest my docs in it. They're so 2014.

[Kaliber in reply to dhccpa]

yes , it does wake me back up , I’m taking the lowest amount of estrogen available, higher doses would probably do more things I would notice.

Yea my doctors almost laughed when I’ve asked for it in the past. This time was different because it was a last ditch effort. 2024 Rotflol.

❤️❤️❤️

[dhccpa in reply to Kaliber]

Practice makes perfect!

[Ian99]

Thank you for such an informative post. Definitely one for future reference. Best of luck.

[StayingOptimistic]

how is your mental status? You are not scared?