Genetic testing-how useful is it? - Advanced Prostate...

Advanced Prostate Cancer
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Genetic testing-how useful is it?

HopingForTheBest1
HopingForTheBest1

My experience with genetic testing is as follows-

Was initially introduced to this concept when I had my biopsy in June 2018, and had samples sent two separate times to Foundation Medicine. Not enough tissue available to perform their test of approximately 400 genes.

Several months later I was told about the Color saliva 30 gene cancer test. Easy enough to do, and not at all costly. Came back positive for BRCA2, which likely explains why I now have APC. Have done a lot of research on this, and have met two well regarded genetic researchers/oncologists. I expect that after I become castrate resistant from my current therapy (6-7 months now of Eligard, Zytiga, Prednisone and Xgeva) I will need to consider a PARP inhibitor such as Olaparib or Rucaparib.

On Nov 14 had robotic prostatectomy as part of SIMCAP clinical trial. Asked surgeon to make sure that a sample be sent to Foundation Medicine for genetic testing. Was told I didn't need to bother as I will be getting full genetic mapping as part of the trial. Will be following up on this at my next MO meeting in a few weeks.

I am hopeful that I will be able to have targeted/precision therapy based on my own genetic makeup. Has anyone had any type of genetic testing, and what has been your experience?

Happy new year to all.

23 Replies
oldestnewest

Why not make a simple call--to Foundation One---and ask them. Your Doc. cannot guarantee what genetic testing will be done for the trial. You now have enough material removed by having the RP for the test to be properly done by Foundation One/Medicine.

For the trial they may do a Blood Genetic Evaluation--can it be equal to an evaluation of the Prostate Material--I do not know. I know that when Foundation One cannot get Prostate Material they have a blood evaluation---is it to equal?

As to your other question, I was not 2 months past my RP, when I had the full Monte Evaluation by Foundation One. I understand today when they do it you may be also have them at the same time check, for the PD-L1 marker, and the AR-V-7 Gene Splice. Not sure but ask. The PD-L1 can make you a candidate for Keytruda later, and the gene splice is predictive if Zytiga and Xtandi will work if needed.

Things have changed since I did mine 3 years ago. So you will need to ask the advocate questions to satisfy you. If it gets real technical, ask to speak to a Doc. there in Genetic Research.

Nalakrats

Lyubov
Lyubov
in reply to Nalakrats

Hard to keep up with the changes in these areas, isn't it? That's why this site is so great & contributions such as yours so helpful.

Nalakrats
Nalakrats
in reply to Lyubov

Thanks

Nalakrats

Ran2599dy
Ran2599dy
in reply to Nalakrats

Do you happen to know the difference between the Guardant Health 360 test and the Foundation One Test. I had the Guardant test two years ago with no mutations. Also, with PC how often should you have one of these tests?

gregg57
gregg57
in reply to Ran2599dy

To my knowledge, Guardant 360 is a liquid biopsy that looks at circulating tumor cells vs. Foundation One which is a tissue sample biopsy. I do see that Foundation One is also offering a liquid biopsy.

There are advantages and disadvantages to both approaches. There's information online on this subject if you do a search.

Nalakrats
Nalakrats
in reply to Ran2599dy

This is a Question for an Advocate that answers the Phone----use their 800 number which you can find on their web site. My understanding is the Guardian is done from Blood and the Foundation is done from saved Prostatic Material from a Biopsy or a RP, but that they also have a Blood Test, when no material is available. Also as I stated before, as a member, I get info thru their portal on new things they are doing and testing for, new trials. So what I did 3 years ago, I think they now do more than the original 328 Gene evaluations. Another nice thing with these folks is you instigate the procedure, so you are always copied, and so is your doctor, with results. And if they find mutations, they have a list of drugs either being used or in Trial for a particular Mutation, and the contact info as to trials. And in my case since I do research, I can talk to a Doctor Of Genetics, and She answers some questions for me. She all ready saved me a flight and a 1,000 dollars, by taking her advice.

Nalakrats

Ralph1966
Ralph1966
in reply to Nalakrats

Hi Nalakrats,

Why the Urologist don't check for the genetics of the removed prostate whenever they send it to the pathologest after radical prostatectomy?

Is this because they hope that there will be no recurrence?

Should everyone in this forum who get a biochemical recurrence do genetic check?

Nalakrats
Nalakrats
in reply to Ralph1966

I cannot speak for everyone. But typically as with my Urologist Surgeon, who has been doing Pca for 20 years, knew not much of Gene Mapping. Oncologists do! My suggestion, only a suggestion is to call Foundation One---800 number on their web page, and speak to an advocate who will answer the phone. They are not doctors, but they are very smart on this subject. Make a list of questions, and be ready. That is what I did 3 years ago. They e-mailed the consent form, I took to my Urologist and explained what I learned--he signed them and 3 weeks later we had the results. I wish the results were better, but at least we know what treatment course I may need in the future---of course Praying real hard I will not need them.

You also get call backs from Doctors who are Geneticists if you have questions the advocates cannot answer.

With the report, make sure you ask for a personal copy if you do the gene mapping. Any Gene Mutations, you get a list of what drugs are available today for them, and where all clinical trials world-wide are being held, with contact e-mails, and tel. Numbers.

And you get a portal, for future contact, and once a client you are always a client.

Meaning communication does not stop. But is up to you to initiate.

Nalakrats

Ralph1966
Ralph1966
in reply to Nalakrats

Does a PPO insurance cover the expenses?

Nalakrats
Nalakrats
in reply to Ralph1966

Foundation One can tell you--they have listings of all insurance companies.

Nalakrats

Ahk1
Ahk1
in reply to Nalakrats

Thanks, Nal for the info.

Once you know you have a germline DNA defect (BRCA2), you can be sure that all your metastases have it too. Unfortunately, your prostate tumors are not the same as your metastatic tumors. Metastatic tumors are more evolved and will show more genomic changes.

As you say, PARP inhibitors have demonstrated effectiveness in germline DNA repair defects. Probably, carboplatin will prove to be equally effective. You will have to get them on a clinical trial (or pay an enormous cost out-of-pocket for the off-label drug) - there are a list of clinical trials with various PARP inhibitors in combination with other medicines in this article:

pcnrv.blogspot.com/2018/02/...

There is one other very rare genetic defect (MSI-Hi/dMMR) for which there is an approved therapy - Keytruda. That's it, so far. There are other clinical trials for a few other common somatic (tumor) genomic defects (e.g., PTEN loss, ERG-TMPRSS2 fusion, p53, etc.)

Castration resistance occurs whether or not you use ADT - maybe 2 months faster with it. The BRCA2 drives the genome towards castration resistance faster. Prostate cancer-specific survival is better with ADT, however.

Ahk1
Ahk1
in reply to Tall_Allen

TA, you said something very interesting here, I have never heard about it :

“Castration resistance occurs whether or not you use ADT - maybe 2 months faster with it. ”

Are you sure about this please?

one of the main reasons I keep delaying it and what I hear from some folks on here is that it makes resistance sets in EARLIER.

please when you have a chance, can you elaborate?

Thanks

Tall_Allen
Tall_Allen
in reply to Ahk1

In fact, in another response, I just quoted Dr. Duchesne talking about her TOAD randomized clinical trial of early vs deferred use of ADT. She wrote:

"One of the most thought-provoking findings was that the development of the castration-resistant phase occurred significantly earlier in the men who started treatment after a delay, a counter-intuitive finding. This may again be linked to treating low volume disease before it grows resistant clones."

Here's the full study:

thelancet.com/journals/lano...

Evidence from analysis of pre-ADT prostate tumor tissue is that androgen independence starts early in the cancer's development process:

journals.plos.org/plosone/a...

Androgen receptor (AR) mutations have been identified in metastases - it is part of the natural history of genetic breakdown that occurs as cancer progresses. There are over 1,000 genetic mutations that have been identified. Many code for androgen independence by various mechanisms. The cancer cell "tries" them and the fittest ones survive and replicate the most, coming to predominate over time. ADT may first kill off the hormone-sensitive clones, but the hormone-insensitive clones were always there.

Hidden
Hidden
in reply to Tall_Allen

Hi TA,

Your second link is what I've been looking for!

By the way, have you looked over Foundation Medicine's services?

I've checked over Care Oncology, did not see personal benefits, can finess Metformin without buying into their COC protocol, liked you mentioned in another thread.

Tall_Allen
Tall_Allen
in reply to Hidden

Foundation One and Caris are major genetic info suppliers. They depend heavily on the genomic characteristics of the biopsied tumor - but we know there is great heterogeneity across tumors. Guardant 360 is a blood test that looks at cell-free DNA, so it probably picks up DNA from lots of metastases. It is not FDA approved, and I've heard it is very expensive (around $4000).

cfrees1
cfrees1
in reply to Tall_Allen

I'm curious about that castration resistance statement too. I haven't heard that before. Do you have a source?

Tall_Allen
Tall_Allen
in reply to cfrees1

see above

Ahk1
Ahk1
in reply to Tall_Allen

Thank you, sir

cfrees1
cfrees1
in reply to Tall_Allen

That is so interesting. I developed CR after 1 year on Lupron and have been regretting that treatment thinking that I should have waited. This puts my mind at ease. Thanks.

cfrees1
cfrees1
in reply to cfrees1

My mutation was also a DNA Repair defect, ATM, so that is what contributed to my advancing to castrate resistance so quickly I guess.

sammamish check this thread

Had genetic testing at Rocky Mtn Cancer Center. Identified the ATM GENE mutation, explains the 9 direct family members deaths of advanced cancers. To date, none of my treatment has been focused on gene mutation. Varly new to APAC, but hopeful for more info/experiences here on HU

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