SIGNATERA TEST

Gizmo77

Hello to everybody,

Does anybody have any experience with Signatera test (Natera company - commercial test)?

I just started the chemo (CMF) and asked my dr - how they are measuring the efficiency of the treatment, and what is the way

to detect what is happening in the body after the treatment. She told me about this test, and started to dig up, but I really need help.

So, please, if anybody knows about this, or if anybody can ask their own Oncologist about this, please let me know.

Thank you!

blue22

So is your doctor going to use Signatera? Do you mind me asking what stage you are?

I have read about it, am interested in it, but have not used it or any of the other ctDNA tests. I am collecting information at home for the next time I visit my oncologist.

Gizmo77

Hi,

I am stage I , Er+/PR+,HER2 -. (I am 66).

Thank you for your reply. It is so hard to get the right info. That would be great if you can get the opinion of your dr. Do you have any other idea how we can get more info. This test is new, the company from CA made this in 2015, and in 2018 they started to sell as a commercial. As a sales person says it is very promising because, as she said, it traces the smallest amount of cancer cells in the blood, based on DNA molecular test of specifics of the tumor of specific person - so it is personalized, so it sounds better then the markers. What is confusing is, they do not have enough time and data, I think, to really see is it beneficial for us, and will not make us more crazy. I belong to people who want to know and I am anyway making dr crazy with my questions and analytic approach.

moth

Hi, I know yesterday there was some discussion at the San Antonio Breast Cancer Symposium about testing for circulating tumor dna. It definitely isn't standard of care yet. I think the difficulty with the test is let's say that you do find ctDNA. Then what? All ER+ treatment assumes you will be on hormonal therapy which helps prevent recurrence. So will the hormone therapy deal with the ctDNA or not? Should someone with ctDNA have more chemo? I think a triple neg might be tempted to have more chemo since they can't use hormonal therapy; but maybe keytruda would be better. I don't think we have data yet on this to make a decision.

I think what is encouraging is that statistically, for most early stage patients, surgery is curative. The chemo and hormone therapy are extras to lower risk of recurrence. What grade was your tumor? What was your Oncotype score?

I would trust the treatment plan, do your chemo, take your hormonal therapy for the MOs recommended duration and just feel safe that you're following current standard of care.

blue22

There are a few companies in the same field, and I am (when I have extra time in the evening and can focus) trying to compare them. I am familiar with Natera, both through my career and through a few people who I know who either used to work there or work there now. They initially focused on pre-natal testing by looking at DNA from a fetus in the blood of a pregnant mother. Looking for ctDNA is a very obvious next step. So although they may have been in cancer detection recently, the technology overlaps with what they have been doing for a while.

For me, the implications would be to use it to monitor my next phase of chemo, which my Dr. is trying to decide on now. Although I am stage III, I am at high risk for recurrence, so after finishing all standard of care treatment we are looking into additional treatments. Natera has a clinical trial that is very close to what I am interested in, but I don't qualify.

NorCalS

Hi. I’m TNBC, diagnosed as stage 3c/4. Started treatment in June of 2019 (AC+T, lumpectomy, axillary dissection, radiation, Xeloda) and ended treatment in November is this year. I just had my blood drawn for the natera test to monitor circulating tumor cells to get a jump on any recurrence. Since I’m at a high risk of recurrence, MO thought this new technology would help monitor status (currently NED) and is less invasive than regular scans. During covid times, this method seems a lot easier with less close exposure to others. I was told it takes about three weeks for the personalized test to be ready.

jennyjo20

Hi Norcal, Gizmo, and Blue,

I have also looked into MRD testing with Natera. Did any of you end up being tested? Were the results helpful? Did it guide treatment decisions? I can see how the results have the potential to complicate things, especially for HR+ BC since you are expected to stay on endocrine therapy regardless. I know monitoring this closely wouldn't be the right approach for everyone, but for some of us "need to know everything" types, I can see the benefit. For anyone out there who has had this testing done, I am interested in hearing about your experience.

scrunchthecat

Hi everyone,

I am Stage IV HER2+. I have been NED for 6 years. I just discontinued Perjeta, one of the two drugs I was supposed to be on "for life," because some data is emerging that once people with my profile become NED we may stay NED. My oncologist today suggested that I discontinue Herceptin, the second of the two drugs, have my original tumor sequenced by Signatera, and then get tested periodically for circulating tumor cells that might indicate a reocurrence. It's not standard of care, but there might be ways to pay for it. I told my oncologist that I would like to wait a year before considering it. I wonder if anyone else is considering this.

sj

NorCalS

Jennyjo20,

I just saw your post. Sorry for the late response. I submitted all the samples for the Signatera test, but unfortunately, the pathology sample from my lumpectomy did not have enough cells to use for the test. Portions of the pathology sample was used to test for PD-L1 to see if I could qualify for a Keytruda trial, so I’m not sure if that’s the reason there wasn’t enough cells for the Signatera test. I was really disappointed that this didn’t work out. I hope others have better luck with Signatera

BCSucks1

my doctor offered me a ctDNA test (and they are looking at tissue samples) so I could be part of a trial for stage 3 breast cancer and at least 2 years post surgery. I did the text but then backed out of getting the results because the trial was to take an end stage breast cancer drug for a year and hope for the best. Honestly there were so many unknowns. I’m still torn on the decison

blue22

BCSucks what was the clinical trial? I would consider taking more drugs.... only because I had IBC.