PET Scan Results

[Murph256]

Can anyone help me interpret my PET scan results from yesterday, and suggest possible courses of action? They seemed bad, but not disastrous.

“Focal uptake in the right prostate bed (max SUV 5.3) as well as the right lesser trochanter (max SUV 4.5), not present on the prior study, suspicious for recurrence.”

It seems I definitely have a met in my prostate bed. Is there a chance it is still localized? I had full pelvic radiation 5 years ago. Can the area of the prostate bed be irradiated again?

The second location on my femur seems ambiguous. I have osteopenia in that hip. I also walk a lot, 40 miles a week. Also, am I correct in assuming that an SUV 4.5 is a marginal reading and could be a false positive? Also, that hip aches after walking. Could that uptake be the result of inflammation and not cancer?

I assume I will go back on ADT plus an anti- androgen when I meet with my MO next month. I will probably avoid docetaxel at this time, due to its toxicity.

Comments, suggestions, corrections?

[GP24]

The recurrence in the prostate bed will not harm you in the foreseeable future. I would just observe this. Single bone mets are often false positives. Therefore I would observe that too. ADT is just necessary to bring the PSA value down.

[Murph256 in reply to GP24]

My doubling time has become alarmingly fast. It’s something like 6-8 weeks. I think my MO will insist on ADT plus an anti-androgen.

[GP24 in reply to Murph256]

This is an overview of the salvage options after radiation: ncbi.nlm.nih.gov/pmc/articl... I would recommend SBRT radiation which allows to radiate the trochanter at the same time as the recurrence in the prostate bed.

[Murph256 in reply to GP24]

Thank you. That’s a great recommendation, and what I was thinking.

Also, is it possible that my cancer is not systemic and was localized in my prostate bed all along?

[GP24 in reply to Murph256]

You wrote: "My doubling time has become alarmingly fast". This indicates that the tumor has spread and is not localized in the prostate bed. I would use SBRT and ADT. See the EXTEND trial: pubmed.ncbi.nlm.nih.gov/370...

[MoonRocket]

Hip discomfort\pain could be bursitis.google.com/search?q=hip+bur...

[fast_eddie in reply to MoonRocket]

I have that or something similar. I use foam roller on side of my left leg (IT band) and left glute. That helps if I can remember to do it each day.

[SeosamhM]

Hey, Murph. Your interpretation of all the information is mine. My only question is whether there was a complementary, comparative scan to identify non-PSMA exhibiting tumors and/or confirm/deny PSMA indications. This has been my experience.

Your SUVmax information seems to match my understanding. Based on my latest PSMA PET and my discussions with my RO two weeks ago, the "false positive" aspect of PSMA is basically ignored by using SUVmax comparisons. An SUVmax around 5 is typically met with a surveillance plan. I would be surprised if your MO will recommend chemo, and agree that they will likely advise a return to ADT. Truly sorry about that.

40 miles a week! Heroic! Honestly, I would naturally trust your instincts since you are so active. I would ask if a focused scan like an MRI might be indicated for your hip. Good luck.

[Tall_Allen]

All of your SUV max readings are marginal. What kind of PSMA PET scan did you have? The old ones, Pylarify and Ga-68- PSMA-11 are excreted quickly from the urinary tract and cause false positives in that area. The newest kind, 18F-rhPSMA-7.3 (Posluma), doesn't cause that problem.

[Murph256 in reply to Tall_Allen]

TA, this is what is says on my results. (I have no idea how to interpret it):

“TECHNIQUE: Positron Emission Tomography/ CT scintigraphy performed scanning from the skull base to the midthigh, after the intravenous administration of 8.4 mCi F-18 Pylarify IV. Limited nondiagnostic CT performed for attenuation correction and localization only.”

[Tall_Allen in reply to Murph256]

Pylarify

[Murph256 in reply to Tall_Allen]

Got it. Thank you.

[spencoid2 in reply to Tall_Allen]

why doesn't everyone use the newest one?

[spencoid2 in reply to Tall_Allen]

is this the old Ga or something newer 68Ga-gozetotide also the web site for Posluma says that it can have false positives in the prostate bed as well

" Risk of Image Misinterpretation in Patients with Suspected Prostate Cancer Recurrence: The interpretation of POSLUMA PET may differ depending on imaging readers, particularly in the prostate/prostate bed region. Because of the associated risk of false positive interpretation, consider multidisciplinary consultation and histopathological confirmation when clinical decision-making hinges on flotufolastat F 18 uptake only in the prostate/prostate bed region or only on uptake interpreted as borderline."

[Tall_Allen in reply to spencoid2]

False positives are less likely with Posluma.

[tango65]

Consider getting a 3 T MRI of the pelvis and the femurs and see if there is cancer in those areas. The radiologist can determine if the bone marrow is abnormal in the trochanter and if there is a tumor in the prostatic fossa.

[NecessarilySo]

In your bio you need to include the years. I'm trying to understand PSA progression but cannot.

[Murph256 in reply to NecessarilySo]

I’ve been on intermittent ADT since March of 2019. Most recently, I went off of ADT in December of 2022. My PSA registered .1 in August of 2023. Based on my past history of a 3.5 month doubling time, my PSA should have registered .2 in November 2023. However it registered .4 last November. I realize I need at least another data point in February of 2024 to get a more accurate indication of my doubling time. Nevertheless, the jump in my PSA was enough to alarm my MO ro the point where his ordered a PSMA PET scan.

[Bowmaster]

Good day bud . I am having the same problem as you and as of beginning of October my PSA was 109.9 and going up fast . The PET scan showed new recurrence in the prostate bed and around it . Since November I am on hormonal therapy and two days ago i had new test blood test and the PSA has come down to 55 thank god . Here is what I am on . Xtandi 40 mg four pills every morning and Reseligo 10,8 mg implant w ampulko-strzykawce goserelinum under the skin in my stomach every three months for now . So far I only had one implant and end of next month I will be getting the next . Then end of April I will have to go for new evaluation before a panel of 10 doctors which will decide where we go from there . Just so you know that implant in the stomach is a chemical castration to stop the PSA all together . My testosteron level was goin up way to fast ! We had no other choice but to castrate ! Not a nice thing to do but hey I am 69 and have had pretty good life so far thank God ! Good luck to You, Me and all the guys out there with our problem !!! LIVE AND LET LIVE !!!

[Murph256]

Thank you. And good luck to you as well.