Signatera Test. Is it truly helpful and worthwhile?

@sosophia245

Agree.

@peggydobbs it's definately confusing, all the different tests! I would only say, the most important thing is to find a qualified oncologist that you truly trust. It's fine to get opinions here, but we're not medical professionals. Some doctors refuse to order either the Signatera or the Oncotype test due to the fact that neither is 100% reliable.

I have been taking the Signatera test for a number of years. It is but one test or tool in the toolbox that doctors and me use to assess either one of my 2 Stage 4 cancers. A single test and a single blood tumor test neither my doctors nor me rely on, get upset about, etc. We look for trends, rate of increase, and other confirming indicators.
Specifically, I did it for a removed ovarian brain tumor that was sent to Signatera in Feb 2024. I registered 0.47 - so not negative. But low. We watched it climb slowly to 7.88, and combined with my other tools of assessment, put a plan of action in place. But then it dropped to 7.0. Not doing anything special but retested and yes jumped to 10.51 in Dec 2025. Combined with PET, tumor markers, etc pivoted to weekly chemo in early Dec. My early March 2026 test showed my number dropping to 0.19. Now just a few more chemo treatments, PET looks better, CA125 way down. So my various tools once again confirmed each other. I meet with my oncology team next week but I suspect he won’t expect me to get to 0. Chemo will stop, we will keep me on some maintenance drugs, and I get to go back to monitoring and living my life. I understand my small “c” cancers are chronic conditions so tools for monitoring are very important to me, and their trends over time become equally important. Good luck!!

I had a Gardant Reveal which is similar to signatera. It took a month to get it back, and since i had a bone marrow transplant with a donor who was male. The Guardant people had been confused to my XY chromosomes as i checked female. Once my DRs office notified me they replied to them i had a transplant. My test came back negative. I also will need another one in 3-6 months. I only wanted it as my sister passed away May 31st and never wanted to take these tests. I told her i take most if not all i am offered.

I say take the tests....they are just a tool to help keep us alive. I have metastatic breast cancer, NED for 3 years, and take the Signatera test every three months. Best of luck to you on your journey.

I have stage 1a triple negative. I have requested this Natera test from my new oncologist. After some serious disagreement and discussion he finally agreed it was probably the only tool we have to follow me. My kidney fxn is suboptimal and i have MGUS. Both these make it difficult if not impossible to safely have chemo.

@hsminc It's a good diagnostic aide. Because it can find cancer recurrence months before physical scans, and it offers a non-invasive way to monitor treatment response over time.

@beenthere2x i totally agree. If this new oncologist had not agreed to do it, I would have looked for anothet. Because my tumor is small 6.4mm, grade 2 with no LVI and huge surgical margins, the “powers that be” do not consider it worth monitoring - or they believe the “science” is not there yet. But it is my body and I want this test!

Hi @hsminc ,
I just read here that you have TNBC. My sister had Stage 2 and was treated successfully over five years ago now. She had lumpectomy after chemo. She got NED and CPR. I think yours was caught even earlier so you may not require same treatments. My sister had AC, Taxol, and Keytruda right after it was approved for TNBC. I had to educate her oncologist that Keytruda even was approved! That was the same oncologist I had 1/2025 who diagnosed me with ET and then changed it to MPF 2/2025. I feel that oncologist was trying to treat everything and was not up to date as each type of cancer has so many new treatments being learned about it all the time!
Have a blessed day!

After my BM last year and started on an AI this test was not offered to me. Only the oncotype testing was done which was below 25. Chemo not indicated for me.
I did my own research on the Signatera test and wondered why it was not offered to me. My surgery and cancer care is with a top cancer facility in the country. But then I changed my breast oncologist (closer to home) and I, myself, brought up the test and it was done. A negative result. I am back with my former providers where I had my surgery now. It is due again in September and will ask my onco to test again. Yes, I agree with all - it is simply a tool in the box. Just like the cancer markers. But I believe (& I could be wrong here) for a positive Signatera test follow up cancer testing is done and the test results not ignored...unless very low?
My personal feeling is to ask for the test if it is not offered to you. But that's my personal opinion.
Everyone is different in their treatment plan for cancer. Every cancer is different.
Yes, discuss with your physician and take it from there. I am glad I had it done.
But and it's a big but - you want that negative result, so it is scary waiting for the result!
That is THE worst thing about this test. The wait period for a result.
Blessings to all!