From my understanding, it definitely sounds like your husband’s CEA is the kind that is a good predictor! My mom’s is as well, although on a smaller scale (went from an 18 to a 10 with 4 rounds of Folfox and scans show tumor shrinkage of 40%!).
For your husband’s to go from 100000 to 69 is surely a great sign!
Caregiver to my amazing mom (68)
10/1/18 DX with rectal cancer; CEA 17 at diagnosis
MRI/CT/PET puts staging at T3N2M0
Trying total neoadjuvant therapy—chemo first, then short course radiation, then surgery
Completed 8 rounds of neoadjuvant Folfox 11/5/18 - 2/11/19
Current CEA 6.2
Me: 34, first colonoscopy 11/16/18—normal! Come back in 5 years.