Test Details
Methodology
Quantitative methylation-specific polymerase chain reaction (PCR)
Result Turnaround Time
7 - 10 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
MGMT (O6-methylguanine-DNA methyltransferase) is a DNA repair enzyme that is involved in the repair of damage caused by a variety DNA cross-linking compounds, including alkylating agents. Increased methylation of the MGMT gene promoter region causes diminished or silenced expression of the gene, making cells more sensitive to DNA damage. The relationship has been shown for glioblastomas and alkylating agents such as temozolomide (Temodar®).
Special Instructions
Please provide a copy of the pathology report. Sample submission without a copy of the pathology report may delay testing. Please direct any questions regarding this test to customer service at 800-345-4363.
Limitations
Preparation of DNA from tissue samples is dependent upon the quality of the provided specimen. Inadequate DNA extraction may occur in a significant number of paraffin-embedded samples.
Custom Additional Information
Approximately 40% to 50% of glioblastoma multiforme (GBM) tumors exhibit MGMT gene methylation. Retrospective studies have shown that detection of MGMT promoter methylation in tumor samples is associated with an increased likelihood of a favorable response to temozolomide.
Specimen Requirements
Specimen
Glioblastoma specimens in formalin-fixed, paraffin-embedded (FFPE) tissue blocks or slides
Volume
FFPE tissue block or eight unstained slides at 5 μM and one matching H&E slide or nine precut unstained slides from a paraffin block in 5-μM sections
Minimum Volume
50mm2 total tumor area is required for testing. Two unstained slides at 5 μM and one matching H&E slide or three unstained slides at 5 μM.
Collection Instructions
FFPE tissue block or eight unstained slides at 5 μM and one matching H&E slide or nine precut unstained slides from a paraffin block in 5-μM sections
Storage Instructions
Maintain blocks/slides at room temperature.
Causes for Rejection
Tissue is not primary brain tumor; tumor block containing insufficient tumor tissue; tumor fixed in a heavy metal fixative; broken or stained slides; decalcified specimens
References
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 489280 | MGMT Methylation Assay | 60252-4 | 489281 | Result: | 60252-4 | |
| 489280 | MGMT Methylation Assay | 60252-4 | 489268 | Methylation Score: | 64083-9 | |
| 489280 | MGMT Methylation Assay | 60252-4 | 489283 | Block Number: | N/A | |
| 489280 | MGMT Methylation Assay | 60252-4 | 489284 | Background: | 77202-0 | |
| 489280 | MGMT Methylation Assay | 60252-4 | 489299 | Methodology: | 49549-9 | |
| 489280 | MGMT Methylation Assay | 60252-4 | 489286 | References: | N/A | |
| 489280 | MGMT Methylation Assay | 60252-4 | 489282 | Director Review: | 72486-4 | |
| 489280 | MGMT Methylation Assay | 60252-4 | 480903 | Microdissection Performed | 8100-0 | |
| Order Code | 489280 | |||||
| Order Code Name | MGMT Methylation Assay | |||||
| Order Loinc | 60252-4 | |||||
| Result Code | 489281 | |||||
| Result Code Name | Result: | |||||
| UofM | ||||||
| Result LOINC | 60252-4 | |||||
| Order Code | 489280 | |||||
| Order Code Name | MGMT Methylation Assay | |||||
| Order Loinc | 60252-4 | |||||
| Result Code | 489268 | |||||
| Result Code Name | Methylation Score: | |||||
| UofM | ||||||
| Result LOINC | 64083-9 | |||||
| Order Code | 489280 | |||||
| Order Code Name | MGMT Methylation Assay | |||||
| Order Loinc | 60252-4 | |||||
| Result Code | 489283 | |||||
| Result Code Name | Block Number: | |||||
| UofM | ||||||
| Result LOINC | N/A | |||||
| Order Code | 489280 | |||||
| Order Code Name | MGMT Methylation Assay | |||||
| Order Loinc | 60252-4 | |||||
| Result Code | 489284 | |||||
| Result Code Name | Background: | |||||
| UofM | ||||||
| Result LOINC | 77202-0 | |||||
| Order Code | 489280 | |||||
| Order Code Name | MGMT Methylation Assay | |||||
| Order Loinc | 60252-4 | |||||
| Result Code | 489299 | |||||
| Result Code Name | Methodology: | |||||
| UofM | ||||||
| Result LOINC | 49549-9 | |||||
| Order Code | 489280 | |||||
| Order Code Name | MGMT Methylation Assay | |||||
| Order Loinc | 60252-4 | |||||
| Result Code | 489286 | |||||
| Result Code Name | References: | |||||
| UofM | ||||||
| Result LOINC | N/A | |||||
| Order Code | 489280 | |||||
| Order Code Name | MGMT Methylation Assay | |||||
| Order Loinc | 60252-4 | |||||
| Result Code | 489282 | |||||
| Result Code Name | Director Review: | |||||
| UofM | ||||||
| Result LOINC | 72486-4 | |||||
| Order Code | 489280 | |||||
| Order Code Name | MGMT Methylation Assay | |||||
| Order Loinc | 60252-4 | |||||
| Result Code | 480903 | |||||
| Result Code Name | Microdissection Performed | |||||
| UofM | ||||||
| Result LOINC | 8100-0 |