...I have spoken with the onc. Each specialty has their own story, and individual surgeons may offer more than others. Often oncologists' "unresectable" patients do get resected. Patients do need to (re)search and advocate for themselves.
Sometimes multistage surgery or multimodal treatments are done in regional or national medical centers. Some first stage surgeries on mCRC may be done for medical necessity, like (impending) obstruction. Then some successful chemo with lack of spread might provide a springboard for a second surgery.
Simple 5FU based chemo has been done nearer and even through some surgeries, as described in a number of Japanese papers. Degree of surgical injury, wound healing, type of chemo and medical/legal environment influence the proximity between surgery and chemo. The Japanese were more advanced on simple oral chemo and immune treatments 20-30 years ago. Today, the closest US analogs might be xeloda instead of UFT; cimetidine, celecoxib, JHS Coriolus Super Strength for PSK, and perhaps other parts of the Life Extension
list.
In the US there can be a lot of problems getting technically aggressive care beyond trials - drug availability for more antimetastatic oriented formulations, supernutrition in hospitals beyond "standard", medical conformity, economic risks with legal self interests.