Update Type: New Tests
Test Updated: 08/31/2022
Test Overview
Test Methodology

Methylation Array

Test Usage

This methylation profiling assay is intended to provide supplementary information for the diagnosis and should only be interpreted by a qualified neuropathologist. In neuro-oncology, several studies have illustrated that methylation profiling enables the classification of neurological neoplasms with greater precision and greater reliability than is achievable by morphologic, immunophenotypic and clinical means alone. When used in conjunction with traditional pathologic methods, methylation profiling results in reclassification of a significant proportion of cases (approximately 10-12%), many of which also altered WHO grading which would result in significantly different patient management. In addition, methylation profiling has enabled the discovery and subsequent diagnosis of new neoplastic entities with distinct biology, clinical behavior, and potential management.

Reference Range *

Interpretive report provided.

Test Limitations

This methylation profiling assay is intended to provide supplementary information to aid in diagnosis. Correlation with histopathologic and clinical findings by a qualified neuropathologist is required for a final, integrated diagnosis. A negative result does NOT exclude the presence of a neoplasm as the limit of detection varies widely among the different neoplasms classifiable by this assay.

Test Details
Days Set Up
Thursdays
Analytic Time

12-20 days

Soft Order Code
NMETH
MiChart Code
Neuropathology Methylation Array
Laboratory
Molecular Diagnostics
Section
Molecular Diagnostics
Specimen Requirements
Collection Instructions

For formalin-fixed, paraffin-embedded tissue, a 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 on each level) with associated H&E stained slide are also acceptable. Decalcified tissue or other fixatives will be accepted, and the assay attempted; however, this specimen type may result in failed testing due to degraded nucleic acid. Both blocks and slides should be stored at room temperature. A Diff-Quik or Papanicolaou stained aspirate smear (preferable containing a high percentage and overall amount of neoplastic cells is also acceptable; however, extraction will result in destruction of the slide(s). A digital image of the slide(s) must be collected prior to extraction and retained for a minimum of 10 years from the specimen collection date. Store at room temperature.

Alternate Specimen
For exhausted formalin-fixed, paraffin-embedded blocks, the original Hematoxylin and Eosin-stained slide(s) and/or immunohistochemistry slides (after digital scanning) may be extracted at the discretion of the Pathologist evaluating materials for extraction. The extraction process will result in destruction of the slide(s). A digital image of the slide(s) must be collected prior to extraction and retained for a minimum of 10 years from the specimen collection date.
Previously extracted DNA from a CLIA certified laboratory may be accepted; however, the extracting laboratory must take responsibility for ensuring that there are adequate viable, neoplastic cells within the extracted sample.
Normal Volume
Formalin-fixed, paraffin-embedded tissue; Diff-Quik stained aspirate smear, Papanicolaou-stained aspirate smear.
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
81479, 88381-TC
Fee Code
NA122, NA037
Pro Fee CPT
G0452-26, 88381-26
NY State Approved
No