I have had a few chemo breaks.
During folfox cycle, each time it was only for one week with no discernible increase in CEA, actually, checking my "book" CEA went down even with the week break.
Different story with Irinotecan. One week break CEA went up from 180 to 289. Then another emergency break, my DH was admitted to ICU with seizures, that break CEA climbed to 535. After treatment was established on a 2 week cycle it went down and for the next 4 treatments bounced between 415 - 418.
My biggest treatment gap was a month and CEA rocketed to 555.
My non-professional opinion is that a week off doesn't hurt as long as it is not done say like every other cycle. I believe that for folks like me it is essential to maintain treatment regularly.
That being said, I absolutely detest infusion, but I have no other options.
DX Jul 2014 Stage IVb CRC metastatic, unknown primary, CEA 1826
Inoperable, Chemo for life
MSI: not tested
29 Jul 14 Port
30 Jul - 19 Jan 2015 Folfox (12 cycles) CEA 164.5
9 Feb 15 - 20 May Flofiri failed (6 cycles) CEA 417.0
17 Jul 15 - Initiated Vectibix CEA 555.5
17 Jul 2015 - 14 Jan 2016 Vectibix
8 Feb 2016 - 11 Apr 2016 Xeloda
26 Apr 2016 Hospice