Test Overview
Test Methodology

Methylation-specific real-time PCR

Test Usage

MGMT (O-6-methylguanine-DNA methyltransferase) is a DNA repair enzyme that is associated with resistance to DNA-alkylating therapies employed in the treatment of gliomas. Methylation of the MGMT promoter occurs in 30-60% of high grade gliomas and 30-90% of low-grade gliomas. Several studies have shown MGMT promoter methylation to be associated with silenced MGMT expression, improved survival and enhanced chemosensitivity. In elderly patients with reduced tolerance to more aggressive chemoradiation regimens, MGMT methylation status may also have therapeutic implications. For these patients, monotherapy with the alkylating agent temozolomide is recommended for patients whose tumors demonstrate MGMT promoter methylation while radiotherapy is recommended in the absence of MGMT methylation. This assay detects MGMT promoter methylation using methylation-specific real-time PCR (MethyLight).

Reference Range *

*Reference ranges may change over time. Please refer to the original patient report when evaluating results. Interpretive report provided.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

Methylation of CpG sites other than those covered by the primers and probes in this assay cannot be excluded.

Test Details
Days Set Up
Monday - Friday
Analytic Time

3 - 10 days

Soft Order Code
MGMT
MiChart Code
MGMT Promoter Methylation
Laboratory
Molecular Diagnostics
Section
Molecular Diagnostics
Specimen Requirements
Collection Instructions

A formalin-fixed, paraffin-embedded tissue block containing an area with a high percentage of neoplastic cells (for micro-/macro-dissection) is preferred. Unstained, UNBAKED slides (5-8, 10-micron slides; 10-15 if few neoplastic cells are present) with associated H&E stained slide are also acceptable. Decalcified tissue or other fixatives will be accepted and the assay attempted, however these may result in failed testing due to degraded nucleic acid. Both blocks and slides should be stored at room temperature.

Normal Volume
Formalin-fixed, paraffin-embedded tissue. Extracted DNA is also acceptable if extracted in a CLIA certified laboratory.
Additional Information

By ordering this test the clinician acknowledges that informed consent has been obtained from the patient as required by applicable state or federal laws and the ordering clinician has authorization from the patient permitting MLabs to report the test results to the ordering clinician. Test includes microdissection billed as a separate additional charge. Test includes pathologist interpretation of results billed as a separate additional charge. This test is not available without interpretation.

Billing
CPT Code
81287, 88381-TC
Fee Code
NA066, NA037
Pro Fee CPT
G0452-26, 88381-26
Prior Authorization
The Prior Authorization form is required for this test. Click here to download the PDF.
Resources