What experience has anyone had with the Signatera blood test?

Update: I was in the ER in Charleston, SC, this past Sunday. I quasi fainted at CHS. So EMTs took me to the hospital. Turned out to be dehydration, sleep deprivation and low electrolytes. I received oral potassium and recovered. Made the flight just in time and drove back from MCO to Fleming Island, FL.

Today it appears I have low potassium again because I started leaning leftward and almost collapsed. Then I discovered the tiny blisters I noted this past weekend, are in fact a specific eczema: https://www.firstderm.com/dyshidrotic-eczema-dyshidrosis. Great: a different skin IRAE. And 4 months after wrapping up nivo.

Here we go. 2026-06-16 signatera = clear (first since 2025-12). 2026-06-16 CT: breast and axillary node enlargement near port. Biopsy. Then cultures. Biopsy radiologist suspected lymphoma. Finally last Saturday (2026-07-11) WBC cloning came back: negative. Axillary node: benign. Breast mammogram, ultrasound: benign. Quite bizarre experience to grow an A-cup involuntarily. MRI: pelvic nodes mild increase again, identical iliac node as reactive through biopsy in 2025-12. Oncologist unconcerned: follow up in 2026-09 to see.

For someone reason I have new stuff all the time. Twice so far I have had my eyes go wild with silver flakes and weird vision changes. IRAE? If so, probably endocrine glands fried by nivo: thyroid is almost gone. Mayo Oncology told me: see an opthamologist.

Hematology wants me to do another panel DNA test to figure out what life long anemia I have.

In summary: never ending. But I am still here.

Went to AC, NJ last week: fun! Nice weather! Good food! In a prayer I promised that I would visit Santee, SC, if I came out clean. So this weekend I will fly there (through Orlando and Charleston) to have a prayer of gratitude. Why Santee? Well: I went there for work and was inspired by the small faithful community.

@jaxfl, how are you doing?

I had a stomach acid attack but did not know so I called the Mayo MD on call. She told me: local ER immediately. Turns out it was acid so Pepcid fixed it. Then the CT showed kidney stones (tiny) on the left side. The past week three came out. Caught one on camera and zoomed in.

Plus, the Nivo rash is back in full force on my arms and hands and chest. 10 weeks after finishing nivo. My eosoniphils were 4X baseline last month and 3.4X baseline yesterday. So that explains it. Mayo gave me another Rx for a topical steroid tub.

Walking is improving, then going back to difficult and then back to improvement. Very odd.

Had my last adjuvant nivolumab last Friday (2026-03-13). The 13th on the 13th. MD cleared me for a 5 month signatera hiatus and next imaging is 2026-06. So he appears to consider me low risk at this point. Time will tell. Going on vacation today through next Sunday to celebrate.

My daughter has has great experiences with the use of the Signatera blood test. Aside former ct scans and MRI tests, the Signatera is able to detect onset of cancer cells that detected so early that the location of that cell is not yet determined. The CT scans and/or MRI imaging is then ordered.

CT and MRI yesterday 2026-03-12 clear. No signatera today. Will ask MD at my 9AM appointment. Last nivo at 11AM today.

@jaxfl Thank goodness!

Results published yesterday 2026-02-02: negative. Praise the Lord!

My 2026-01-15 signatera is still pending. Got a vague verbal statement that there is a retest. Then I was told this is uncommon but has no bearing on results. Results should be here today 2026-02-02 but nothing so far. I was also told there is a spike in tests (makes sense: huge revenue increase = more tests) and the winter storm wreaked havoc on the TX lab.