Interested in others thoughts with findings, whether 'not detected' or 'detectable'. Mine is not detected. (yes, I have done plenty of reading and consulted with several docs-but this is very new with prostate cancer).
Experiences with Guardant360 liquid b... - Advanced Prostate...
Experiences with Guardant360 liquid biopsy?
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NanoMRI
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What is not detected? Tumor cells?
And I take it you don't have any of the 12 or so HRR\HRD mutations..i.e. BRCA1\2, ATM, etc.
That's is more typical result you have. There's nothing actionable i.e. Parp, inhibitors, etc approved as of now.
Liquid biopsies are only useful if there is a high metastatic tumor burden or progressing rapidly. It is only recommended for men with many visible metastases who are CR:
ncbi.nlm.nih.gov/pmc/articl...
Also, there is low concordance between tests.
jamanetwork.com/journals/ja...
Patients with fewer metastases can get more reliable readings from somatic tests.
Genetic tests fom a tumor tissue biopsy or from a removed cancerous organs like in an ovarian cancer.
The best would be a biopsy from a metastasis.
Right. When it's based on biopsy tissue, it's called "somatic." The conceptual advantage of a liquid biopsy is that there is DNA from all the metastases, not just the ones that are biopsied.
Another advantage of biopsy is that cell histology and IHC can be ascertained too.
Good to know. Thanks
as I have commented elsewhere, these statements of your puzzle me -? The medical oncologist and hematologist I consult with would not agree with your "only useful" statement.
Patients are well-advised to be diligent in asking their doctors -"what is the evidence for that?" I have shown the evidence for my statement.
I've just sent back my blood sample for a Guardant360 liquid biopsy so will let you know what results it comes up with.
Excellent, thank you! My interest/hope is to hear from other men who have actually had a liquid biopsy test.
In Australia the Guardant 360 liquid biopsy cost 5000A$
In the UK it's £1450.
Did the biopsy of your liver Mets confirmed that they are PC Mets? What is effective against liver Mets? I have to Google it. I am just wondering would not be a better investment of your money to pay for a genetic analysis of your liver Mets than to try the liquid biopsy at this stage. Did you missed the window of opportunity to send out the liver tissue biopsy samples to comprehensive genetic analysis and all the rest what TA recommended to do with the tissue biopsy samples?
"Another advantage of biopsy is that cell histology and IHC can be ascertained too."?
About liver Mets:
google.com/search?q=prostat...
AbstractLiver metastasis causes nearly half of death from solid tumors. Metastatic lesions, to the liver in particular, can become detectable years or decades after primary tumor removal, leaving an uncertain long-term prognosis in patients. Prostate cancer (PCa), a prominent metastatic dormant cancer, has the worst prognosis when found in the liver compared to other metastatic sites. These metastatic nodules display a therapy resistance in the liver pro-metastatic microenvironment; the resistance appears to be conferred by both dormancy and independent of dormancy when the nodules emerge. Within the review, the molecular underpinnings of how the liver aids and protects PCa cells seeding, colonization and resistance will be discussed.
I think carboplatin is the best thing for me to try next. I start on Monday. Others have reported good results from it but I'm under no illusions that my prognosis is pretty bad now I have liver mets.
It looks like that the liver is protecting the cancer from the chemotherapy (at least that is my understanding as not a doctor) the liver has that capacity to protect against toxins. Could you ask your doctor if you don't have some other options? What's the point of poisoning yourself with chemotherapy if it is not effective on the Mets inside the liver? I actually don't know but that is the risk. Could you ask for a second opinion about the effectiveness of the carboplatin from a top medical oncologist? We have here in Sydney a clinical trial with BAT and carboplatin. Maybe you could consider that. My oncologist is the lead oncologist for that clinical trial. I am not a doctor just providing the information.
How long will it take to get the results of the liquid biopsy?
Here is the link to the phase 2 clinical trial in Sydney:
classic.clinicaltrials.gov/...
Some Google search results about BAT plus chemotherapy:
I've had two second opinions - one being Professor DeBono at Royal Marsden and they all say carboplatin is the best treatment.I also asked for experience on here of carbo with liver mets and got some positive results feedback.
I found a following information about liver Mets chemotherapy. I am not sure if it would be applicable to your case but maybe yes?
Chemotherapy & Targeted Therapy for Liver Metastases
mskcc.org/cancer-care/types....
And a Google search results about carboplatin effectiveness on liver metastasis:
google.com/search?q=carbopl...
Thanks Seasid.
From the above Google search results:
Platinum-based chemotherapy in patients with castration-resistant prostate cancer and hepatic metastases.
Journal of Clinical Oncology
Volume 41, Number 16_suppl
June 2023
Abstract
e17063
Background: Patients with metastatic castration-resistant prostate cancer (mCRPC) and hepatic metastases face a dismal prognosis. In fact, the majority of phase 3 trials show no benefit of novel treatment modalities including Lutetium PSMA radioligand therapy (LuPSMA-RLT) in comparison with standard therapies for the subgroup of visceral metastases. In aggressive variant prostate cancer, the addition of platinum resulted in a clinically relevant improvement of progression free survival (PFS) and overall survival (OS). Whether adding platinum is also beneficial in unselected mCRPC patients with hepatic metastasis is unclear. Methods: We retrospectively analyzed mCRPC patients diagnosed with hepatic metastasis and treated with platinum-based chemotherapy or LuPSMA-RLT in three German centers (Hamburg, Essen, Munich). Patients with pure neuroendocrine prostate cancer were excluded. Survival rates and 95% confidence intervals (CI) were compared using the Kaplan Meier method and the logRank test. Results: A total of 84 mCRPC patients with hepatic metastasis who had received at least one platinum-based therapy and 32 patients treated with LuPSMA-RLT were evaluated. Median age at treatment initiation was 67 and 73 years. Patients had undergone a median of three treatment lines (83% ≥ 1 new hormonal agent (NHA); 87% ≥ 1 taxane based chemotherapy) before initiation of platinum based chemotherapy and a median of 4 treatment lines before LuPSMA-RLT. Median time to initiation of 1st platinum-based chemotherapy after diagnosis of liver metastases was 55 days. In total, 37% received carboplatin/cabazitaxel, 26% cisplatin or carboplatin/ etoposide, 11% carboplatin/docetaxel, and 26% other platinum-based combination therapies. In the platinum-treated group, 52.6% and 27% of the patients did not show progression at 3 and 6 months after treatment initiation as compared to 44.1% and 19.3% of the patients who received LuPSMA-RLT with a median PFS of 3.1 and 2.4 months, respectively. At 6 months 71.3% of the platinum-treated patients and 56.6% of the LuPSMA-RLT were alive. Overall, BRCA1/2 status was available for 53 of the platinum-treated patients, 15% of whom had a pathogenic alteration in either gene. This small subgroup was found to have a similar OS compared to the overall cohort. Conclusions: Platinum-based chemotherapy showed promising activity in mCRPC patients with hepatic metastasis. Given the high unmet medical need, platinum-based combination therapies should be further evaluated prospectively.
Platinum based chemotherapy Lutetium Radioligand Therapy
Number of patients evaluated 84 32
Median age (median; IQR2) 67 (61-73) 73 (66-80)
Previous treatment lines (median; IQR2) 3 (2-4) 4 (3-4)
rPFS 3-mo rate (95% CI)
6-mo rate (95% CI) 52.6 (42.6 - 64.9)
27 ( 18.6 - 39.1 ) 44.1 ( 28.4 - 68.6 )
19.3 ( 8.5 - 43.9)
OS 6-mo rate (95% CI) 71.3 ( 61.8 - 82.3 ) 56.5 ( 41.1 - 77.6 )
ascopubs.org/doi/10.1200/JC...
Thanks Seasid. Unfortunately my carbo session yesterday was cancelled due to a high temperature and high CRP so they've put me on a 5 day course of amoxicillin so hope fully I can start next week.
Could they reduce the dose and do it weekly? I am not a doctor but I believe that something like that is possible. Can you ask some other hospital infusion clinic about that possibility? I hope that you will recover. My sister just finished with her second cycle of Taxol plus Carboplatin infusion. She has two cancers. Localised Ovarian cancer plus third stage cancer of the uterus. She will have one more cycle of Taxol plus Carboplatin. After that she will get for 20 days high radiation therapy for very limited time similar to HDR brachytherapy. Unfortunately you can't have it. Could you do the radiation with Elektra Unity MRI linac? They have one of this machine in Royal Marsden hospital? My understanding is that you have too many small Mets in your liver, but the MRI linac is high precision up to 0ne millimetre accurate and the MRI gives a real time control of the radiation even if you are breathing etc. can you ask for that? If not Royal Marsden hospital than you could come to Sydney Darlinghurst we have one machine here in Genesis Care. You could inquired by the RO here he should know more than me. Could you say more about your Mets in your liver? I was the RO patient here.
They won't give any carbo while I have such a high CRP (210 when reference range is 0 - 5) indicating I have an infection because depleting WBC more could be fatal for me.
I have discussed various types of RT of the liver mets with my MO but he says they are too extensive and now growing quite large for it to be an option.
I really hope that your CRP will stabilise soon. We have to think about some option for you. I am not a doctor but still I would not trust them to come out with the best solution alone. We should also think and explicitly ask the doctors about the feasibility of the possibility if we come out with one.
I think Brysonal was getting some white blood infusion during his chemotherapy. You may find it in his profile. I am sure you are in good hands but still not everyone is treated equally.
Thanks
What is your treatment now? I understand that carboplatin is stopped. My sister is on chronic, ongoing doxycycline 100mg daily and she looks fine after two cycles of Taxol 150mg/m2 plus carboplatin. Hopefully she will stay fine because she wants to continue working otherwise they will reduce her income to 65% of her current income and they will pay the money with 2 month delay here in Serbia.
MO tells me this biopsy showed it is adenocarcinoma PCa ( not neuroendocrine). NHS are doing a limited genomic test of the liver tumour sample.
I guess you didn't find anyone privately to do histology and IHC?
Looking forward to hearing from others that have had a liquid biopsy for prostate cancer.
Responding to comments within, the doc who recommended and wrote the script for mine is board certified in medical oncology and hematology. She, and the radiation oncologist I consult with, support my (relentless) investigative efforts, often outside of standard US clinical guidelines, to do all I can to delay my need for ADT/chemo, for as many years as possible.
Despite comments put forth, the Guardant360 results have indeed been useful, providing additional confidence to my diagnostic and treatment strategies, which are guided by a most excellent multidisciplinary team that thinks well beyond standard US clinical guidelines.
Had I followed standard US clinical guidelines, I would Not have:
Screened for this disease and caught it when I did, in 2014, at age 57.
Had mpMRI, two actually, before my biopsy.
Added genomic testing to my investigative efforts, when it did not have US FDA approval.
Relied on <0.010 as best indicator post RP, giving my spreading cancer time and obscurity.
Tested very frequently with different labs in different US states and other countries.
Traveled abroad for Ga68 and even better nanoMRI, before US FDA approved PSMA imaging.
Had salvage pelvic lymph node surgery that got me to <0.01, which held for two years.
Had second Ga68 followed by Pylarify for comparison, at 0.030, in 2022, in Houston, Texas.
Had the Guardant360 liquid biopsy; the central topic of my post.
Today, six years after ePLND, ten years since my diagnosis, holding very low stable usPSA 0.03X range, no ADT/chemo.
All the best to all of us fighting this beast.
I recently had the Guardant 360, which registered negative all around. My Oncologist said he finds very hard to believe I don’t have any circulating tumor cells; and said we’ll likely need to do it again later on. I recently went HR/CR, but was originally Dx with high volume metastases.
interesting. I wonder if the suggestion to do it again has any basis that your's was 'wrong', or just a guess idea to try again? My new to me oncologist could not believe how many and volume of pelvic mets I had with salvage ePLND, and being after RP and salvage RT. So he asked for a second pathology opinion; this required having slides shipped from hospital in Belgium to Houston, TX. (that was easy and I was not charged for the shipping). Well, a 'major cancer center' in Houston concurred with the Belgium hospital pathology. My oncologist said he had never seen this before. Well I asked, how many of your partients had their common iliac and para-aortic pelvic nodes removed and biopsied? He said none. My reply - so why are you surprised? I wonder how many times your oncologist has prescribed the Guiardant360?
So, you’re suggesting this brand of liquid biopsy is not reliable? or not as reliable as other brands of liquid biopsy? or not as reliable as tissue biopsy (which doesn’t measure CTC)?
Sorry, but it’s not clear to me exactly what point you’re making and what, if anything, it has to do with how many times my MO has ordered this brand of test.
Not trying to be ‘flip’ in any way; just not getting the point you’re making. Perhaps it would have been better if I originally mentioned all my metastases thus far, per scans, are bone and not soft tissue?
Apologies for delay (bucket of unrelated reasons 
I in no way sense you are 'flip' - I sincerely want to hear from others who have used this test. (And I have heard before my 'points' are confusing 
I do not have an opinion of this test - only done this one and of course some reading. With any investigative tool the question I have is what to do with the results, detected or undetected, positive or negative, etc.
You shared your oncologist finds it hard to believe yours is 'undetected' and wants to repeat. Do they anticipate a different result? Does it matter whether mets are just bone and/or tissue? So far my identified mets are pelvic lymph nodes only.
The side story I shared was intended to not dispel this test, but I thought a parallel example of the many challenges we face when a doc questions investigative results. When my new to me oncologist questioned the biopsy findings from my salvage lymph node surgery, I was not sure what to do. Why would he question it - how could it be wrong?
I appreciate the Guardant360 is a lab test - not a visual judgement opinion such as pathology. I would like to have total absolute confidence my 'clear' Guarndant360 result is 100% reliable and a most favorable sign. Two docs seem to think so. But as I am the patient facing this beast I am always cautious.
I hope this is clearer - ? Best!
Thank you for the clarification. Much appreciated!
I believe my MO was guessing the liquid biopsy might not be sensitive enough to detect a low level of CTCs; and perhaps at some later time when a higher volume of them may be present it would register. My impression was he felt confident in its ability to detect actionable mutations at this stage; but of course mutations are generally subject to change as disease progresses. So another liquid biopsy in the future may yield different information than this initial one did.
I’m not well enough educated on this topic to know whether or not there are any substantial differences between the different brands of liquid biopsies available. I wouldn’t be surprised to learn that there’s just not been enough time and data accrued yet to yield that kind of information.
One thing I have read is that sometimes ‘incentives’ from provider companies may be a factor in clinicians choosing which brand of treatment or test to use when all other factors are essentially equal in their understanding. So there might be a bit of that at play when it comes to which brand of liquid biopsy gets chosen. E.g., one observational analysis indicated more MOs selecting Xtandi over Zytiga for first line ARDT even though studies have indicated Xtandi after Zytiga is generally more successful than the other way around. The difference noted was the manufacturer of Xtandi offers honorariums to clinicians which is not available from the manufacturers of the generic form of Zytiga; otherwise, both drugs appear to have a nearly identical efficacy in the front line of ARDT use.
As I understand it, blood biopsy is a newer method of somatic testing; but perhaps not yet proven to be as reliably definitive as tissue biopsy, the traditional somatic test method. Soft tissue somatic testing tends to be more reliable than testing samples of metastases from bones, basically because high grade samples from the bone are more difficult to harvest.
Best of luck with your future tests and treatments!
excellent - very helpful - thank you - agree on all. Helps me have further confidence in my result, within parameters, and possibly next one on a reasonable timeline. I test usPSA very frequently - will ahead of standard clinical practice. My intent is to not give this beast time nor obscurity.
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