To PET or not to PET

[Jvaughan0]

I have been on nubeqa and orgovyx for over six months now. Blood draw this week shows my PSA level at <.10 beginning 30 days of starting those two drugs. My MO suggested I have a regular PET scan. No need for a PSMA scan because my PSA is basically undetectable. I am having trouble rationalizing the need for a PET and plan to talk to the MO. I am hoping to get insights from the group. I have been battling PCa for 10 years: prostate removed, ADT, and three courses of radiation over that time. The more I think about it, I see another source of radiation as not helpful.

[Xavier10]

I guess I would ask him what PET scan he had in mind. If a choline or PSMA, I think they are wasting time. I did a Choline scan with <.1 (after radiation and at my own request, which my RO was very kind to agree to to shut me up) and it just came back with a bunch of mumbo jumbo in my humerus and inguinal gland that my RO told me to ignore. The PSA needs to be higher for anything to register properly for one of those scans. Maybe one of the new ultra sensitive MRI scans (that insurance probably won't pay for) would be useful just in case you have one of the types of PCa that doesn't put out PSA.

[Jvaughan0 in reply to Xavier10]

I believe in being proactive. It has helped me fight cancer for ten years. ...just not sure such a scan would be helpful at this point.

[Jvaughan0]

Regular is probably a poor word choice. Having undergone so much radiation in the past, I'm reluctant to undergo a non-PSMA PET scan. I'm aware that some cancer cells don't produce PSA and they generally develop rapidly and are even more deadly, but I question the benefit of another scan.

[treedown in reply to Jvaughan0]

I understand your concern. My scans had a positive on CT and a negative on bone scan on a metastes at T6. That was the reason for so many in my case. Perhaps your MO has a uncommunicated reason?

[Tall_Allen]

I agree with you that there is no purpose to a PET scan now.

[Jvaughan0]

Spoke to MO today... The thinking is to monitor for possible transition to small cell cancer which wouldn't be PSA sensitive. Maybe some logic there, but I'm unconvinced.

[Sailing-Todd in reply to Jvaughan0]

My husband had around 20% de novo neuroendocrine cells at diagnosis two years ago.

They have just done his first PET scan. They wanted to wait until his PCa/PSA was quiet before PET scanning him so they could assess the neuroendocrine component. There are different tracers for different sorts of cancer cells I gather. A sort of baseline clear of PSA. There wasn’t much to see apparently.

They will be repeating the PET scan in three months to confirm direction of activity.

[Jvaughan0 in reply to Sailing-Todd]

Wishing the best for your husband. Thanks for sharing.

[MateoBeach]

PSMA PET ie the best available scan to identify progression while on your hormonal regimen I would do one every six months.

[Jvaughan0 in reply to MateoBeach]

PSA has to be there to begin with for a scan to make sense. I don't see the logic.

[Nusch]

My PSA is undetectable and I do a PSMA/Pet CT scan annually. My doctor asks to do so for comparison. I follow his advice.

[Jvaughan0 in reply to Nusch]

Following a professional's advice is key, but using a PSMA scan to locate a nonexistent PSA source doesn't seem logical.

[Doctorsceptic]

regardless of the radiation, the purpose of any test is to answer a question and to guide decision making. The extra tests therefore seem pointless and expensive.

[Jvaughan0 in reply to Doctorsceptic]

Agreed

[Cooolone]

CT & Bine scans every 3-6 months???

Haven't heard, read or seen in any study such a timeline. Can you provide where you've gotten this information? Curious...

[treedown in reply to Cooolone]

My MO told me that and I have had it repeated on this forum. I also lived it recently in relation to a spot showing on my T6, but that was for clear intent. Additionally, I didn't question thee above sources because I thought I had read it in the NCCN Guidelines but having just reread it I see my error as far as that source. I will have to return to that source in more detail when I get to my computer. Thanks for questioning it, I will clarify with my MO on Monday.

[Cooolone in reply to treedown]

I understand we are all different, but such a frequent interval while such a low expressed PSA I fail to understand the clinical significance other than introducing more anxiety and worry for the patient. Of course I recognize and understand we are all different and for some it may provide some significant diagnostics, I just haven't seen this anywhere. I would want yearly PSMA PET scans but know it wouldn't provide any advantage and possibly worse radiation toxicity at some point. Especially when PSA is stable or undetectable...

Definitely of you find it, please share. I appreciate it.

[j-o-h-n]

From A and i (Pca for dummies)

A non-PSMA PET scan refers to a type of positron emission tomography (PET) scan that does not use prostate-specific membrane antigen (PSMA) tracers. PSMA PET scans are commonly used in the context of prostate cancer to target and visualize prostate cancer cells due to their high expression of PSMA.

Non-PSMA PET scans utilize different radiotracers to target other conditions or to visualize different aspects of the body. Some examples include:

FDG PET Scan: Uses fluorodeoxyglucose (FDG), a glucose analog, to identify areas of increased metabolic activity. It's commonly used in oncology to detect a variety of cancers, including lymphoma and certain types of solid tumors, as well as in evaluating neurological disorders.

Gallium-68 PET Scan: Different from PSMA PET, gallium-68 can be combined with other tracers for different types of cancers. For instance, gallium-68 DOTATATE PET scans are used to visualize neuroendocrine tumors.

Choline PET Scan: Uses choline, a radiotracer, which can be useful in imaging prostate cancer, especially in cases where PSMA PET is not available or suitable.

C11-Methionine PET Scan: Used primarily in brain imaging to assess brain tumors, given that methionine is an amino acid incorporated into proteins.

The choice of a non-PSMA PET scan depends on the specific clinical question and the type of cancer or condition being investigated.

Good Luck, Good Health and Good Humor..

j-o-h-n

[Jvaughan0 in reply to j-o-h-n]

Thanks j-o-h-n

[j-o-h-n]

You're very welcome.....keep on keeping on........

Good Luck, Good Health and Good Humor..

j-o-h-n

[dmt1121]

It's too soon to be useful. When PSA rises above .5ng/ml to 1.0 ng/ml, then you will get reliable results.