Happy summer, folks. This is a posting inspired by smurtaw's recent post on Guardant 360 testing (see: healthunlocked.com/advanced.... Apparently tested folks are not only getting cancer biomarker indications from this test, but also a "Tumor Mutational Burden (TMB)" score.
I really only know Guardant 360 by rumor and research. It is (per the manufacturer literature) a test that is "...FDA-approved for complete genomic testing across all solid cancers, providing doctors guideline-complete genomic results in 7 days from a simple blood draw to inform treatment decisions." So...
Does anyone have any thoughts or experiences with Guardant 360 (or its competitors, if they exist) that they'd like to share? While I categorically discard the hype of "complete genomic testing" (a moving target, for certain!), it does seem like this test fits into standard of care...somehow, somewhen...
Thanks! - Joe M.
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SeosamhM
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Thanks. It makes sense that free-floating tumor "trash" density is critical to detection. See smurtaw's reply about his MO use as a screening tool - it seems to be an interesting application, but certainly not one currently use in our SOC.
The problem is to get enough genetic material from the tumor in the blood sample. It may work in people with multiple metastases and a PSA greater than 5 or according to other studies greater than 10. The larger the tumor load and the PSA the higher the chances of getting a good study.
I just got my results back for my Guardant-360 blood test and it detected an alteration biomakers PIK3CA V448_L452del (1.1% of cfDNA). My appt. with my medical oncologist is next week. What the heck does that mean and how does it relate to my PCa? The report indicated Alpelisib as an associated FDA-approved in other indication. In other words, not FDA approved for prostate cancer. It also provided information for a local near me clinical trial availability for this biomarker defect. Any comments or suggestions would be appreciated.
I was also wondering, after looking at the Guardant website, when the second of these two panels might be indicated or beneficial:
"A Guardant360 CDx report contains both professional services, which includes 74 genes, in addition to the FDA-approved report, which includes 55 genes."
"Guardant360 TissueNext is an analytically validated tissue comprehensive genomic profiling panel that includes TMB, MSI status, and PD-L1 IHC, if ordered. A Guardant360 TissueNext report includes 84 genes."
Even though both list a total of 84 genes for Point Mutations and Deletion Variants, for example, the TissueNext report lists CHEK2 while the CDx report does not.
Well, if insurance isn't balking - I'm also a sucker for data. I will look into it. You would think the Guardant manufacturer would be pushing for this if only to move it into routine screening status and more $.
Yes, it looks like some "liquid biopsy" tests were approved in 2020, including Guardant. The key language is here:
cms.gov/medicare-coverage-d...
The conditions seem straight forward: Patient has been diagnosed with a recurrent, relapsed, refractory, metastatic, or advanced solid tumor that did not originate from the central nervous system.
While I am still on private health insurance, I always ask my LPN case manager and office staff about these things!
I frankly don't know a thing about any genetic testing costs, or how insurance might or might not cover different tests. I plan to bring it up at my next MO appt... but sounds like a good topic for a new thread!
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No intensification - is doc too laid back?
MO ordered genetic testing of Biopsy core. Results received in July. Did not tell me or post to portal. Venting and questions.
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