cfDNA

[TheTopBanana]

Hello again!

My father’s doctor said that there is important to test cfDNA. This is complete news to me? And I’m a neurotic daughter trying to read everything. Have others had this test done?

[Tall_Allen]

Yes - Guardant 360 had the first test and now Foundation One has one too. They are very expensive, and it is unclear that they are better than tumor biopsies. The theoretical advantage is that they include DNA from germline and all tumors in the body, whereas as a tumor biopsy tells you only about that one tumor. However, not all tumors seem to contribute DNA and correlations have been weak. Also, as with all genomic testing, very few mutations are actionable. It is also a changing landscape- the mutations found early on may be very different from mutations found later.

[TheTopBanana in reply to Tall_Allen]

Is it worth testning cfDNA when on ADT?

[Tall_Allen in reply to TheTopBanana]

I would expect cfDNA to go down to almost nil when starting ADT

[TheTopBanana in reply to Tall_Allen]

One doctor told us it could be worth testning to see if chemo would be relevant?

[Tall_Allen in reply to TheTopBanana]

I don't know of any genomics that would preclude chemo

[TheTopBanana in reply to Tall_Allen]

Ah! This doctor said it was a way to also see how much of the disease that are active?

[Tall_Allen in reply to TheTopBanana]

I don't know what he's talking about.

[TheTopBanana in reply to Tall_Allen]

No I don’t either. So it’s useless with ADT?

[Tall_Allen in reply to TheTopBanana]

I don't understand what you hope to get out of cfDNA. It's very expensive.

[TheTopBanana in reply to Tall_Allen]

Expensive and not worth it?

[Tall_Allen in reply to TheTopBanana]

You haven't explained what treatment decision might be made because of it. If there is no treatment decision to be made, it is not worth it.

[Hidden]

Here's an article comparing liquid vs. tumor biopsy.

biochain.com/general/a-tale...

[TheTopBanana in reply to Hidden]

Thank you!!

[Justfor_]

One and a half year back, searching the web, I found a Swedish startup that advertised a coming genomic test. Don't know if they finally offered it or ended up as vapourware.

[TheTopBanana in reply to Justfor_]

Interesting! Are you also Swedish?

[Justfor_ in reply to TheTopBanana]

Did your doctor asked for cfDNA or ctDNA? (see wikipedia excerpt bellow).

The Swedish startup, I mentioned earlier, is not offering this service at present, but you can get an idea of the price tag: icellate.se/en/services

There is also this Lab in Greece (search Healthunlocked, there are two pertinent threads) : rgcc-group.com/

"Circulating tumor DNA (ctDNA) is tumor-derived fragmented DNA in the bloodstream that is not associated with cells. ctDNA should not be confused with cell-free DNA (cfDNA), a broader term which describes DNA that is freely circulating in the bloodstream, but is not necessarily of tumor origin. Because ctDNA may reflect the entire tumor genome, it has gained traction for its potential clinical utility; “liquid biopsies” in the form of blood draws may be taken at various time points to monitor tumor progression throughout the treatment regimen."

en.wikipedia.org/wiki/Circu...

[Justfor_]

No. Southern European.