Screening Colonoscopy – October 2022 Coding Tip

Colon Cancer is 100% preventable. It starts as a growth inside the colon called a polyp. There are little to no symptoms of polyps growing in your large intestine. The main way we find them is by doing a “screening” test. Medicare provides coverage for screening colonoscopies to patients aged 50 and older. Many commercial insurers are now covering screening colonoscopies for patients 45 and over.

If a provider starts a screening colonoscopy and removes a polyp, or another issue is found and removed during the screening colonoscopy, it turns into a diagnostic service.

To code a colonoscopy for commercial and or Medicaid patients, report CPT code 45378 Colonoscopy, flexible: diagnostic, including collection of specimen(s) by brushing or washing, when performed (separate procedure). Append modifier 33 preventive services to the procedure code to trigger the preventive benefits (no cost sharing) to the patient. If the screening turns into a diagnostic procedure, append modifier PT for a colorectal cancer screening converted to diagnostic test or other procedure.

When coding a screening for a Medicare patient, report HCPCS Level II code G0105 Colorectal cancer screening; colonoscopy on individual at high risk or G0121 Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk.

Modifier 33 is not to be applied to these codes as screening is already indicated in the code descriptions.

Some indications that a Medicare patient is at high risk for colorectal cancer are:

  • personal history or familial history (sibling, parent, or child) of adenomatous polyps
  • colorectal cancer
  • inflammatory disease

Per ICD-10-CM guidelines, “A screening code may be a first-listed code if the reason for the visit is specifically for the screening exam.” That code is Z12.11 Encounter for screening for malignant neoplasm of colon.

When anesthesia is used during a screening colonoscopy, it may be reported separately with CPT code 00812. When a screening colonoscopy turns into a diagnostic colonoscopy, report the anesthesia service with CPT code 00811 and append modifier PT.

  • 00811 Anesthesia for lower intestinal endoscopic procedures, endoscope introduced distal to duodenum; not otherwise specified
  • 00812 Screening colonoscopy

Note that moderate sedation is reported with HCPCS level II code G0500 or, if warranted CPT code 99152-33 and 99153-33 based on time.

1. AAPC Healthcare Business Monthly, March 2022

Diagram of Colon for Screening Colonoscopy

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