I'd agree with going with the NCCN guideline. CT scans are not harmless and in fact are mildly carcinogenic. The guideline represents the best risk/reward.
DW Dx 7/15, 41 yo, st IV, 3+ liver mets: 11.3 cm, 7cm, 3cm. MSS.
KRAS, APC, SMAD4, TP53 mut.
7/15-10/15: FOLFOX+bev. x8
11/15-12/15: SIRT (Y90)
1/16: Toxic Hepatitis, chemo break
4/16: Liver resec. fail
5/16-7/16: FOLFIRI x6
8/16: Liver resec.
8/16-11/16: FOLFIRI x6
2/17: IMRT/Xeloda x25
6/17: CT: Progression. Peri, Lung, Liver mets. FOLFIRI x6
9/17: FOLFIRI+Bev x5.
11/17: CT: Stable. 5FU+bev. maintenance x5
1/18: Surgery for SBO due to internal hernia. 37 days in hospital.