First of all, congratulations on conquering the months of chemotherapy and that you have that obstacle behind you.
I'm not a doctor and I am really no expert in imagiology. So I can only talk about my experience...
In the first CT that I had when diagnosed (1/17) a cyst was also found in my liver. 4mm in segment IV. They weren't really sure what it was, so I made an appointment with a imagiologist who I trust and he made an ultrasound of the liver.
It was not easy to find the damn thing, but when he did, he was POSITIVE it was only a cyst. And now 6 months later I've repeated the CT before my surgery and there it was again, 4 mm in the same place. So I don't worry
Maybe an ultrasound would be a valid option for your Husband?
All the best and keep strong,
Dx @ 29 yo. Mum (22. Mo) & Wife
12/2016: Rectal AdenoCa G2. CEA 4.3. RAS Wild. MSS. IIIB.
01 - 03/2017: 28 RTx + CHT 2,5 g/d Capecit.
03 - 06/2017: Suplemments and Cimetidine.
05/2017: TME/TAMIS + permanent Colostomy CEA 0.5
05/2017: ypT2N2aM0 (4/15), good cCR, limited pCR
06 - 8/2017: 4x CapOx 3,5 g/d (2x Oxi reduced to 80%)
09 -11/2017: 3x Capecit. monotherapy 4g/d