What experience has anyone had with the Signatera blood test?

@babab My surgeon and medical oncologist both essentially say the same about the meaning of the numbers. They seem to be guided by results that show detectable vs non detectable along with pet scans. My surgeon also told me that in my case there were likely not enough cancer cells to show on a cat scan. (I was upstaged to stage 3 after radical cystectomy in Jan 2024. After 4 cycles of chemo it became non detectable for about 11 months. It came back this year with a very low number 0.33 . Nothing showed on CAT scan but based on Signatera PET scan was ordered and showed uptake in pelvic nodes. 2 cycles of Padcev and Keytruda put me back to non detectable . I have PET scan and Signatera coming up after I finish cycle 6 of current treatment in next few weeks .

My Natera results have settled in at 0.24, 0.00, 0.14, 0.17, 0.14, and 0.14. I am 22 months post RC surgery. My oncologist says the test is too new to know exactly what this means. Anyone had a similar experience and what did your oncologist say? Nothing on CT and PET scans.

@jaxfl My oncologist has my Natera blood draw coordinated with port flushes, so they do both at the same time.

I have to take time off work for all these appointments so it is a bit of a hassle to use Natera. My oncologist did offer this as an option.

@jaxfl
I’m sorry you’re going through this. It’s stressful enough without adding process that doesn’t make sense. Maybe it would be better to have Natera send someone to you to do the blood draw at home? It would mean an additional “stick” outside of what happens during your Dr visits but it may be worth it? Alternatively , perhaps escalate to your oncologist or surgeon directly and ask who to speak with about this mayo problem. My original local drs wanted me to use Natera but had no contacts or interest in helping when I told them about issues I was experiencing on the Natera side. Because of “operational”problems and poor communication I originally refused to use them. When I switched to the major ny teaching hospital and Drs I have now, they have excellent direct working relationships and direct contact with Natera and I’ve had absolutely no problems with the hospital or on Natera side since Jan 24.

@jaxfl It makes no sense to send it to MN rather than directly. Billing reasons, I wonder? Costs more to ship it twice.

The test is now showing on the Natera portal. Now I have to wait until the early/middle of next week for the results.

So it turns out Mayo JAX did send it to Mayo MN. Mayo MN sent it out Monday afternoon. It arrived at Natera around 9PM PT / 11PM ET yesterday. I asked the RN why this is so convoluted and she told me Mayo will not change this. So this adds almost a week of unnecessary delay to the process. I did get an email and text message from Natera but this morning the test did not appear on the portal yet.

@jaxfl This is shocking to me! I'm so sorry you're dealing with this issue. I had my last bloodwork done on a Monday and received a text from Natera the next day stating they had received it. (I was surprised how quickly they notified me.). My hospital overnights it via Fed Ex each time.

Still missing in action. I called Natera this morning and they confirmed the order but had no idea why it is not showing on the portal. They also did not yet receive the sample. Mayo has no idea yet what happened. It is very frustrating. I am not sure why in 2025 major organizations cannot get their processes/systems to work properly.