Is radiation to prostate useful if one has bone mets ?

[Tinkudi]

I see many people with bone mets advanced cancer say they took many sessions of radiation to the prostate.

My MO’s never mentioned radiation ever , except spot radiation to pain spots in bones if any when that happens.

Does radiation to the prostate in cancer that is already in bones improve survival ?

[Tall_Allen]

Not if there are more than 3 metastases on a bone scan/CT.

prostatecancer.news/2018/09...

Note: on a bone scan/CT, not a PET scan/CT

[Tinkudi in reply to Tall_Allen]

Thanks Allen. We had done a PSMA. Not a bone scan or CT. That showed more than 3.

[Tall_Allen in reply to Tinkudi]

I know. That's why I explained it for you.

[Tinkudi]

So a PSMA would be equivalent to bone scan/CT or not ?

In the study you linked they have defined oligometastatic as 1-3 DISTANT metastases. And in one place have written “ outside the axial skeleton “.

Can you please explain what distant and axial would mean

[GP24]

A PSMA scan is not equivalent to a bone scan/CT, it detects mets the bone scan will not detect. Therefore if the PSMA scan detects more than three mets, it does not mean that radiation of the prostate will not be beneficial. The number of three is not a sharp cliff. Radiating the prostate when there are three bone mets is more beneficial than if there are four. But radiating when there are four bone mets helps too. Here is an image to illustrate why a PSMA scan is not equivalent to a bone scan/CT:

PSMA scan and bone scan versus number of mets.

[Jenniemae]

my husband has high volume Mets to spine. We were told by local RO radiation not an option due to that. We are meeting with MO at MSKCC this week and will see what they say.

[Tinkudi in reply to Jenniemae]

Did you get radiation ?

[GP24]

Here is an image how beneficial prostate radiation is depending on the number of bone mets detected with a bone scan. It seems to be beneficial up to 8 mets. Therefore STAMPEDE plans to use up to five bone mets in future trials.

JAMA Oncol. 2021;7(4):555-563. doi:10.1001/jamaoncol.2020.7857

[Tinkudi in reply to GP24]

thanks. So you are saying PSMA shows more mets than a bone scan shows and that radiation to prostate can be useful also when PSMA shows more than 5 mets ?

[GP24 in reply to Tinkudi]

According to this analysis of the STAMPEDE trial, yes.

[Derf4223]

I suggest adding a Radiation Oncologist (RO) to your team.

[Tinkudi in reply to Derf4223]

A medical oncologist would not refer to a RO if he thought it would help ?

[Derf4223 in reply to Tinkudi]

I would never assume that if I were you.

[MomOfMaisy]

My husband completed 28 IMRT radiation treatments in March. He was diagnosed in November with 3 small mets on ribs and scapular. The other mets are in lymph nodes and seminal vesicles. The RO said he’s kind of in the middle between low and high volume mets. And his MO feels it’s low enough that he doesn’t recommend chemo at this time. I’m not quite sure what the radiation focused on other than the prostate and immediate area around it, the RO said the mets on the bones were so small on the scan he wasn’t even sure they could pinpoint those with something like SBRT. And he has no pain.