*If prior authorization is not submitted, test may be delayed.
Test Overview
Methylation-specific real-time PCR
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 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.
Methylation of CpG sites other than those covered by the primers and probes in this assay cannot be excluded.
Test Details
3 - 10 days
Specimen Requirements
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.
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.