I was able to get a CT scan at six months post treatment because my spleen was slightly enlarged after finishing chemo, but otherwise I am on the once a year for five years for the CT scans.
Blood work: every 3 months for first year, now at every six months with visits to Onc office to review blood work/side effects follow up, also for five years out from treatment like the scans
Colonoscopy: one year after diagnosis (which was just a little over two months after finishing chemo); then two years from that last one, which puts me at this fall, have it scheduled around my work schedule; if this colonoscopy is also clear, not sure if I go again in two or three years from now, but I hope not as far out as five years, that seems too far away. Funny in that who wants a colonoscopy more frequently, but I will take that prep any day over chemo treatments!
And then most importantly, is the Health Insurance factor, because it all comes down to what they will allow.