Shlyalford is correct, the second one would be diagnostic because the patient is having symptoms so you would use the CPT codes 453XX (last 2 digits depend on what was done, bx, snare, etc.) with the ICD-10 code for the change in bowel habits.So I have another question. Different patient last colorectal cancer screening was done on 8/8/2018 however this patient then had a change in bowel habits so the physician did another colonectal screening (both were coded as G0105). I know that it has to be at least 24 months but I though that if the patient became systemic that we could bill a screening, am I incorrect?