Having SABR radiotherapy to 61mm met on my hip

[konichiwa12]

My Onco told me that my last PSMA scan (August 3rd) showed good reduction in seminal vesical site but an increase in the RH pelvic met. I went for planning session today and wanted to ask what the change in size from the scan last November was for example, had it increased from 3mm to 6mm?The Specialist Doctor told me the tumour is 61mm and on the upper hip bone near to the crest. I asked how much had the size increased and he said not much really it was around that size in November! I was/am gob smacked. The scan shows the white uptake (cancerous areas) as the full width of the both and huge (61x50mmx hip thickness?). The issue is that it hasn't shrunk so that is why they will do the SABR treatment, ie the Abiraterone is not working on the bone met. Is it possible to remove that size of tumour with SABR? It makes me question how long that met has been there and why was it not found on the bone scan or CT scan being roughly 60 mm diameter????

[Tall_Allen]

It may be extensive but not very deep. What was the SUV max and what was the background SUV? Yes, radiation can ablate it. Some are using cryo for ablation. Can they take a biopsy? Does it express AR?

[konichiwa12 in reply to Tall_Allen]

I will need to ask about SUV max & background as I don't know what they are. Is AR Androgen Receptor? Sorry, I'm not stupid but this is all new to me since mCRPC!

[Tall_Allen in reply to konichiwa12]

SUV=standard uptake value - it is a measure of how strongly the radioactive molecule attaches to the cancer cells. It is measured against the background uptake. If it is low, it may explain why it didn't show up on a bone scan.

AR=androgen receptor. If low, it may explain why abiraterone+ADT didn't shrink it.

[Curehunter in reply to Tall_Allen]

How do they measure AR expression? And also SUV?

[Tall_Allen in reply to Curehunter]

AR expression from IHC. SUV from scan.

[j-o-h-n]

They say "medicine is not an exact science it's a work in progress"..... Holy chit we're screwed.....

Good Luck, Good Health and Good Humor.

j-o-h-n Saturday 09/05/2020 1:41 PM DST

[konichiwa12]

I start the SABR treatment on Monday. I will have 5 sessions in total Mon/Wed/Fri/Mon/Wed. I previously had 37 sessions of Tomotherapy of about 2-3 Grays. I am having 50 Grays this time as RO says he is literally going to "Zap" it. For that reason there may be more chance of pain and/or fatigue. For the size of the treatment area and dose intensity I am expecting to get pain (for the first time!). My MO also said:

"I am confident that the SABR will be effective for the disease in the right ilium and that the Abiraterone will continue to be effective on the prostate and SV

Given the result of your PSMA PET CT i do not believe you have anything else to worry about. Easy for him to say but I feel a bit better for the moment.......

Has anyone had similar SABR treatment to a large bone met?

[konichiwa12]

One more thing. My PSA has gone from 3.18 to 6.13 in 8 weeks. Is that significant? My Onco has not mentioned it......