How To Use CPT Code 81321

CPT 81321 describes the full gene sequence analysis for the PTEN (phosphatase and tensin homolog) gene. This article will cover the description, procedure, qualifying circumstances, appropriate usage, documentation requirements, billing guidelines, historical information, similar codes and billing examples.

1. What is CPT Code 81321?

CPT 81321 can be used to analyze the entire gene sequence of the PTEN gene. This code is specifically used for the phosphatase and tensin homolog gene analysis, which is responsible for the production of the PTEN protein. The PTEN gene is associated with conditions such as Cowden syndrome and PTEN hamartoma tumor syndrome. The analysis involves examining the full gene sequence, not just evaluating common variants.

2. Official Description

The official description of CPT code 81321 is: ‘PTEN (phosphatase and tensin homolog) (eg, Cowden syndrome, PTEN hamartoma tumor syndrome) gene analysis; full sequence analysis.’

3. Procedure

1. The lab analyst performs the technical lab test to analyze the entire gene sequence for the PTEN gene.
2. The procedure involves extracting nucleic acids from the patient’s cells through methods like cell lysis and digestion.
3. The lab analyst then amplifies and stabilizes the quantity of nucleic acid for analysis by techniques such as polymerase chain reaction (PCR) or transcription of DNA to RNA and reverse transcription from RNA to make an additional copy of the DNA.
4. The target genes, in this case, the PTEN gene, are detected using methods like nucleic acid probes.
5. The lab analyst analyzes the full gene sequence of the PTEN gene to identify any changes or mutations that may be present.

4. Qualifying circumstances

CPT 81321 is typically ordered by clinicians to diagnose hereditary conditions such as Cowden syndrome and PTEN hamartoma tumor syndrome. These conditions are associated with changes in the PTEN gene, which can occur in cells throughout the body. These changes result in an abnormal PTEN protein, leading to the formation of benign tumors called hamartomas and an increased risk of certain cancers.

5. When to use CPT code 81321

CPT code 81321 should be used when a clinician orders a full gene sequence analysis of the PTEN gene. This code is specifically for analyzing the entire gene sequence, not just evaluating common variants. It is commonly used as a first-line test to diagnose conditions like Cowden syndrome in symptomatic patients with no known family PTEN mutation.

6. Documentation requirements

To support a claim for CPT 81321, the documentation should include:

• Reason for ordering the test, such as suspicion of Cowden syndrome or PTEN hamartoma tumor syndrome
• Details of the full gene sequence analysis performed on the PTEN gene
• Date of the analysis
• Results of the analysis, including any identified changes or mutations
• Signature of the lab analyst performing the analysis

7. Billing guidelines

When billing for CPT 81321, ensure that the full gene sequence analysis of the PTEN gene is performed. This code should not be reported for testing common variants or duplication/deletion variants of the PTEN gene. If the ordering clinician requests physician interpretation of the test and the pathologist provides an interpretation and report, you may additionally report the appropriate evaluation and management code with modifier 26. It is important to note that an MD or DO physician must perform the interpretation, not a PhD laboratory scientist.

8. Historical information

CPT 81321 was added to the Current Procedural Terminology system on January 1, 2013. There have been no updates to the code since its addition.

9. Examples

1. A patient with symptoms suggestive of Cowden syndrome undergoes a full gene sequence analysis of the PTEN gene using CPT code 81321.
2. A clinician orders CPT code 81321 for a patient with a family history of PTEN hamartoma tumor syndrome to confirm the presence of any changes or mutations in the PTEN gene.
3. A patient with breast cancer is tested using CPT code 81321 to determine if there are any PTEN gene mutations that may be contributing to the development of the cancer.
4. A clinician orders CPT code 81321 for a patient with thyroid cancer to assess for any changes or mutations in the PTEN gene that may be associated with the cancer.
5. A patient with multiple hamartomas undergoes a full gene sequence analysis of the PTEN gene using CPT code 81321 to confirm the diagnosis of Cowden syndrome.