Given it’s the liver, this is most likely to be a highly-targeted form of radiation known as SBRT (or SABR). This has the benefit of (usually) minimal systemic side effects when compared with typical wide-field radiation. A lot of work will go into trying to avoid radiating healthy tissue, which may also include inserting tiny fiducial markers prior to the treatment.
As you point out, fatigue is likely, and some nausea is possible. Most folk seem to tolerate this process well, and local tumour control rates are generally very good.
Best of luck for it!
2018 Dx RC, 12cm from AV
Mod diff, EMVI+, LVI+. 4 liver mets
pT3N1aM1a Stage IVa. MSS NRAS G13R
CEA: Nov-18= 14; then 2.0-3.1. Nov-21: 5.4
11/18 FOLFOX x6
3/19 Liver resection #1
5/19 25x pelvic IMRT radiation
07/19 ULAR w ileo, 1/27 LN+
08/19 Liver spot
08/19 FOLFOX x1, FOLFOXIRI x1, FOLFIRI x5
12/19 Liver resection #2
02/20 Ileo reversed
03/20 NED since Dec ‘19
11/21 35mm liver lesion; celiac LN. Some v. small (<2-3mm) lung things
1/22 Planned liver & node resection (TBC)