Generally no, a CT would not detect colon cancer, at least not in the early stages. The only way to reliably detect colon cancer is with a colonoscopy. Did the radiologist suggest any further investigation in their report? Usually they would if there was anything concerning.
I have had lots of scans and a few of them have noted "fecal loading" in my colon, which is nothing to do with cancer. I don't think it is anything to worry about, but you should speak to your doctor about getting a colonoscopy if you're concerned.
Male, 33 @ dx, stage 1 RC (T1N0M0 0/29 LNs)
2016-02 - Cancerous polyp removed during colonscopy, 0.5 mm margin
2016-03 - ULAR & TME surgery, temp ileostomy
2016-04 - DVT, pulmonary embolism
2016-11 - Ileostomy reversal
2018-10 - Another DVT & PE
Clean CTs 2016-08, 2017-03, 2017-09, 2018-04, 2018-09