Does cancer of the cecum show up in blood work?

Not really: There is a marker called CEA that may be elevated in someone with cancer in the cecum, but it's not a test like psa for prostate cancer that can be used for screening purposes. Blood work could show anemia that may be caused by a cecal cancer. The best way to catch it early is to get regular check-ups including stool guaiac checks and screening colonoscopies.

Perhaps indirectly: If bleeding and blood loss sufficient to produce anemia. Looking at blood results is not the way to diagnose colon cancer. Occult blood/guaiac card shows presence leading to colonoscopy for diagnosis. Treatment is right colectomy collecting at least 13 nodes.