CPT® Code 81237

Official Description

EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit) (eg, diffuse large B-cell lymphoma) gene analysis, common variant(s) (eg, codon 646)

Common Language Description

Molecular genetic testing is a critical procedure used to identify specific genetic variants that may be associated with certain diseases. In the case of CPT® Code 81237, the focus is on the EZH2 gene, which encodes for a protein that plays a significant role in the regulation of gene expression through histone methylation. This gene is located on the long (q) arm of chromosome 7 at position 36.1 (7q36.1). The EZH2 gene is part of the polycomb repressive complex 2 (PRC2), which is essential for maintaining the silencing of genes that are not needed for a particular cell's function. The enzyme produced by the EZH2 gene, known as histone methyltransferase, modifies histone proteins by adding methyl groups. This modification can enhance the function of these proteins or lead to atypical functions that disrupt normal cellular processes, such as cell division and proliferation. The specific focus of this testing is on common variants at codon 646 of the EZH2 gene, which is located within the catalytic SET domain. This region is particularly sensitive to methylation changes, which can significantly impact gene function. The identification of these variants is particularly relevant in the context of diffuse large B-cell lymphoma (DLBCL), a type of cancer that arises from B-lymphocytes, which are crucial components of the immune system responsible for antibody production. DLBCL is recognized as the most prevalent form of non-Hodgkin lymphoma, predominantly affecting adults over the age of 60. It is characterized by its aggressive nature and can manifest in various locations, including lymph nodes and extranodal sites such as the gastrointestinal tract, testes, thyroid, skin, breast, bone, and brain. Symptoms of DLBCL may include rapid lymph node enlargement, fatigue, loss of appetite, weight loss, dyspnea, night sweats, and fever. The analysis performed under CPT® Code 81237 aims to pinpoint these common functional variants, which can indicate compromised gene function, by comparing gene segments to identify similarities or differences that reveal the presence of the variant, often equating to a mutation.

1. Indications

The procedure associated with CPT® Code 81237 is indicated for the identification of common variants in the EZH2 gene that may be linked to diffuse large B-cell lymphoma (DLBCL). The following conditions and symptoms may warrant this genetic testing:

Diffuse Large B-Cell Lymphoma (DLBCL) - A type of aggressive non-Hodgkin lymphoma that arises from B-lymphocytes, characterized by rapid growth and potential spread to various body sites.
Age Consideration - Primarily affects adults over the age of 60, making age a significant factor in the indication for testing.
Symptoms of DLBCL - Symptoms may include rapid enlargement of lymph nodes, fatigue, loss of appetite, weight loss, dyspnea, night sweats, and fever, which may prompt further investigation through genetic testing.

2. Procedure

The procedure for CPT® Code 81237 involves several key steps to ensure accurate analysis of the EZH2 gene. The following procedural steps are outlined:

Step 1: Sample Collection - A biological sample, typically blood or tissue, is collected from the patient. This sample serves as the source of DNA for the genetic analysis.
Step 2: DNA Extraction - The DNA is extracted from the collected sample using standardized laboratory techniques. This step is crucial for isolating the genetic material needed for analysis.
Step 3: Amplification of Target Region - The specific region of the EZH2 gene, particularly codon 646, is amplified using polymerase chain reaction (PCR) techniques. This amplification allows for sufficient quantities of the target DNA to be analyzed.
Step 4: Variant Analysis - The amplified DNA is then subjected to sequencing or other molecular techniques to identify any common variants present at codon 646 of the EZH2 gene. This analysis helps determine the presence of mutations that may affect gene function.
Step 5: Interpretation of Results - The results of the genetic analysis are interpreted by qualified laboratory personnel. They assess the identified variants in the context of DLBCL and provide a report detailing the findings.

3. Post-Procedure

After the completion of the genetic testing associated with CPT® Code 81237, the following post-procedure considerations are important:

Patients may need to discuss the results with their healthcare provider to understand the implications of any identified variants. Depending on the findings, further diagnostic or therapeutic options may be considered. It is also essential for healthcare providers to document the results in the patient's medical record and to consider the impact of the genetic findings on treatment planning and prognosis. Follow-up appointments may be necessary to monitor the patient's condition and to discuss any additional testing or interventions that may be warranted based on the genetic analysis.

Short Descr	EZH2 GENE COMMON VARIANTS
Medium Descr	EZH2 GENE ANALYSIS COMMON VARIANTS
Long Descr	EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit) (eg, diffuse large B-cell lymphoma) gene analysis, common variant(s) (eg, codon 646)
Status Code	Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days	XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC)	9 - Not Applicable
Multiple Procedures (51)	9 - Concept does not apply.
Bilateral Surgery (50)	9 - Concept does not apply.
Physician Supervisions	09 - Concept does not apply.
Assistant Surgeon (80, 82)	9 - Concept does not apply.
Co-Surgeons (62)	9 - Concept does not apply.
Team Surgery (66)	9 - Concept does not apply.
Diagnostic Imaging Family	99 - Concept Does Not Apply
CLIA Waived (QW)	No
APC Status Indicator	Service Paid under Fee Schedule or Payment System other than OPPS
Type of Service (TOS)	5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS)	none
MUE	1

90	Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.