Questioning my doctor's comment regarding genetic testing

Today during my appointment with my MO I asked about genetic testing and if that would be appropriate for me sometime in the future. My doctor's reply was: "We don't do genetic testing for prostate cancer here because it will not effect the treatment." Huh? I thought changing the treatment was the reason why you do it in the first place. Am I missing something?

I asked a similar question about a year ago.

Ans: "The genetic sample we need is of the cancer itself and you (me) have nothing we can sample."
To which I replied, "Can't you get the sample from my initial biopsy slides?"
Ans: "It wouldn't do an good, the cancer mutates and we would need to get a genetic workup of the current mutation."

...Jerry

btw: Things may be changing here: as a part of my participation in the ORIOLE clinical trial, they gave me something they called a Color test, "Lastly, the use of the Color Genomics platform (Burlingame, CA), a hereditary cancer assay assessing pathogenic mutations in 30 cancer predisposition genes that account for >90% of the germline mutations known to occur in men with castrate resistant metastatic prostate cancer (mCRPC), will help inform and allow for efforts to advance a more personalized medicine approach to tailor screening and therapies in these men."

Be careful. DO a search here on genetic testing. If you get it done and it's paid for by your insurance carrier, they also get the results! So if let's say you have the BRCA2 gene, you and your children might never be able to get life insurance. Pay out of pocket, maybe get it anonymously. Google it.

Nick

We requested genetic testing and it was done, using my husband's blood. Her was tested for germline (hereditary) mutations like BRCA 1/2 and about 10 others. Fortunately, all negative.

I understand tumors that have metastasized can mutate and you can have a somatic mutation-- ie, not one you were born with but one that developed when the cancer spread.

I understand that they can biopsy the tumor or test circulating tumor cells. Depending on what they find, some chemo's would be more effective than others.

Others probably know way more than I do!

Starfinder,

If you are with one of the large HMOs in California, or perhaps with the VA, they may have a tendency to throw an advanced metastatic prostate cancer patient into one large pool and pour in some sequential "standard of care", and see what works, and what doesn't work, without regard to individual germline or tumor/mets genetics. (Cost/benefits considerations might be at play behind the scenes, too.)

Being advanced metastatic myself, in 2016 I was referred by UCSF for family germline testing at their BRCA clinic at 1600 Divisadero Street, H Building, 4th Floor, San Francisco, CA 94115. (415) 353-9797
I did some family history documentation ahead of time, followed by a saliva sample that was sent to Ambry Genetics in Southern California. The particular test I had was the "CancerNext" test, which tested more genes than a similar "ProstateNext" that Ambry Genetics does. In my case, there were looking to rule out if I may have inherited any BRCA-type or other mutations that might be actionable, beyond the usual standard of care for castrate resistant metastatic prostate cancer. (example: BRCA - LYNPARZA™ (olaparib))

Just last week, another man in a support group I attend was offered a different genetic test, involving a blood draw, after a failed attempt to obtain a sufficient bone biopsy sample of a "met" from his pelvis. It was the Guardant360 test, testing for many of the same mutated genes, but via a method that finds them in the form of circulating cell-free DNA (cfDNA). Google "Guardant360 how it works".

As for insurance and affordability issues, if one cannot get them covered by an HMO or insurance, the costs are not astronomical, and something might be worked-out with the companies for $ assistance.

For men who may be asking such questions either right after initial biopsy or surgery with pathology tissue available, there are other genetic tests that may be used to help assess the cancer, and the likelihood of aggressiveness or recurrence. The OncotypeDX GPS and Prolaris assays are discussed here in a blurb from UCSF.

/urology.ucsf.edu/prostate-cancer-gene-expression-testing-at-ucsf

Charles

I wouldn't say there is nothing a man in your situation can possibly do as a result of genetic testing, but I would say "probably not" and "very little." The only kind of genetic changes that we have an effective medicine for are "DNA repair defects." They tend to increase over time, so that only about 1-2% of men who are newly diagnosed with mets have them. For those men, and for men who have rare congenital DNA repair defects, a PARP inhibitor may be useful.

The only other genetic aberration that there is a medicine for is Keytruda for MSI-H and mismatch repair deficient tumors, but again, those are rare for PC. Cspivak was very lucky in this regard.

Because the tumors change over time, you are more likely to have a treatable genetic aberration later on in disease progression, after castration resistance sets in.

There are some genetic anomalies, like the AR-V7 splice variant, that may mean some drugs may not work well for you, but I think that most MOs would try them anyway.

Tall Allen, Paul has the Tp53 or p53 as it's called. Would this qualify him for keytruda? It's acquired and not in all cells but picked up on his color genomic testing.

Just some food for thought about statins and tp53.

https://www.sciencedaily.com/releases/2017/01/170124124907.htm

For a relevant webinar on early and late stage genomic testing for prostate cancer, click here: https://youtu.be/TRPtM4kjW0E . The deck can be viewed and downloaded at https://www.ancan.org/recorded-calls

Many community standard medical oncologists neither understand nor employ genomic testing for late stage disease. As an advocate, I frequently have to educate patients how to introduce the concept to their medical team.

When standard treatments are no longer effective, and before a man is too sick, genomic sequencing can be helpful. Around 15% of men with advanced disease may benefit from a genomic sequencing by identifying appropriate treatment ...... test providers suggest a higher result. Even if an off-label drug is suggested, it can be a fight to get insurance to approve it ... but based on several anecdotal instances, it is doable.

Onward & upwards, rd