I love Roy's response... spot on. I'm certainly no oncologist or doctor of any kind, but I've been counseling hundreds of EC patients around the world for over 3 years. I'm only 4 1/2 years since dx, and just over 4 years post-op. I've had Signatera testing done every 3 months since Oct 2020.

I admit I'm puzzled when I see others reporting Signatera results while they are stage 4 and undergoing treatments. There's zero doubt your cancer is out and about and will certainly be seen in your bloodstream. But the relativeness of these numbers... I'm a bit suspect of. For many of us, Natera testing is started post-op, when it is believed we've reached NED status from all our chemoradiation treatments and subsequent esophagectomies. Are we truly NED at a month or two post-op... who the hell knows... and even our many doctors can not be sure. And if they tell you that you are now cancer free... They're full of sht... and irresponsible.

But... it's a good starting point, and if a zero baseline is achieved, future Signatera testing will be a good relative indicator of what's floating around in the bloodstream (ctDNA). But this is not the Be All End All... just another tool to monitor us like our scans and endoscopies and symptoms we are feeling. But again... I'm not sure just significance there is from running Signatera tests on active stage 4s receiving chemo treatments.

We do see protein monitoring in general... for CA 19-9, CEA, CA 125, etc. But even these numbers jumping around... can be a bit misleading. But Signatera testing... looking for YOUR cancer's signature in YOUR bloodstream, is different. All the best.

Gary