Pathology/Lab Coding Alert

Learn the genes associated with colon cancer.

Although fecal occult blood test (FOBT) lab tests and various surgical procedures such as colonoscopy have been the gold standard of colorectal cancer (CRC) screening, newer, molecular methods are coming to the fore.

Study the following questions and answers to add the molecular-testing angle to your lab-test coding toolbox.

Recognize Molecular Tests

Question: Are there any genetic tests recommended for CRC screening, and if so, what are they?

Answer: Two clinical lab tests have at least a component that evaluates DNA markers for CRC in a patient specimen.

Cologuard^®: One of the tests uses both a standard fecal immunochemical test (FIT) stool test and a molecular diagnostics test to interrogate 10 DNA markers in the stool specimen. The assay includes an algorithmic calculation to predict possible CRC based on the results of both tests. The commercial test is called Cologuard^®, and the code is 81528 (Oncology [colorectal] screening, quantitative real-time target and signal amplification of 10 DNA markers [KRAS mutations, promoter methylation of NDRG4 and BMP3] and fecal hemoglobin, utilizing stool, algorithm reported as a positive or negative result).

You shouldn’t bill the FIT test (82274, Blood, occult, by fecal hemoglobin determination by immunoassay, qualitative, feces, 1-3 simultaneous determinations) in addition to the Cologaurd test (81528),” cautions William Dettwyler, MT AMT, president of Codus Medicus, a laboratory coding consulting firm in Salem, Ore.

Although the Cologuard test is more sensitive than FIT alone, it has a lower specificity, introducing the potential for false positives leading to more colonoscopies.

Medicare has developed a policy to pay for this test as a screening tool in certain circumstances. The patient must meet these criteria for coverage:

• The patient is between 50–85 years of age
• Patient shows no signs or symptoms of colorectal disease including, but not limited to, lower gastrointestinal pain, blood in stool, positive fecal occult blood test
• Patient is not at high risk for developing colorectal cancer, meaning no personal history of adenomatous polyps, colorectal cancer, or inflammatory bowel disease (including Crohn’s Disease and ulcerative colitis)
• Patient has no family history of colorectal cancers or adenomatous polyps, familial adenomatous polyposis, or hereditary nonpolyposis colorectal cancer.

SEPT9: Another clinical lab test that evaluates CRC genetic markers is the blood test for SEPT9 gene methylation assay. This is the first FDA-approved blood test for colorectal cancer (CRC) screening.

CPT^® 2019 revises the code for this test by adding the underlined word to the definition: 81327 (SEPT9 (Septin9) (eg, colorectal cancer) promoter methylation analysis).

Although the US Preventive Services Task Force (USPSTF) included this test in the screening recommendation statement for average risk patients at least 50 years old, the statement reported the test to have low sensitivity (48 percent) for detecting CRC.

Focus on Tier 1 Codes

Question: Our lab performed a Buccal Colaris genetic test for a patient based on a family history of colon cancer. Is this a CRC screening test, and how should we code it?

Answer: No, Colaris^®, which is test by Myriad Genetics, Inc., is not a screening test for CRC.

Instead, tests such as Colaris^® are genetic tests to assess a person’s risk of developing hereditary CRC, such as Lynch Syndrome (also known as hereditary nonpolyposis colorectal cancer or HNPCC), familial adenomatous polyposis (FAP), and MYH-associated polyposis (MAP).

The tests typically use a blood specimen or buccal (oral) swab specimen and involve DNA sequencing analysis of several genes, such as MLH1, MSH2, MSH6, and PMS2.

Correct coding for the tests involve selecting the codes for the specific gene mutations interrogated, such as the following codes:

• 81292 (MLH1 (mutL homolog 1, colon cancer, nonpolyposis type 2) (eg, hereditary non-polyposis colorectal cancer, Lynch syndrome) gene analysis; full sequence analysis)
• 81288 (… promoter methylation analysis)
• 81293 (... known familial variants)
• 81294 (... duplication/deletion variants)
• 81295 (MSH2 (mutS homolog 2, colon cancer, nonpolyposis type 1) (eg, hereditary non-polyposis colorectal cancer, Lynch syndrome) gene analysis; full sequence analysis)
• 81296 (... known familial variants)
• 81297 (... duplication/deletion variants)
• 81298 (MSH6 (mutS homolog 6 [E. coli]) (eg, hereditary non-polyposis colorectal cancer, Lynch syndrome) gene analysis full sequence analysis)
• 81299 (… known familial variants)
• 81300 (… duplication/deletion variants)
• 81301 (Microsatellite instability analysis (eg, hereditary non-polyposis colorectal cancer, Lynch syndrome) of markers for mismatch repair deficiency (eg BAT25, BAT26) includes comparison of neoplastic and normal tissue, if performed)
• 81317 (PMS2 (postmeiotic segregation increased 2 [S. cerevisiae]) (eg, hereditary non-polyposis colorectal cancer, Lynch syndrome) gene analysis; full sequence analysis)
• 81318 (… known familial variants)
• 81319 (... duplication/deletion variants).