Test Overview
Test Methodology

Multiplex PCR with capillary electrophoresis detection.

Test Usage

EGFR gene mutations occur in 10-40% of non-small cell lung cancer (NSCLC) cases. The most common mutations include exon 19 deletions and the exon 21 L858R substitution which together comprise ~85% of all EGFR mutations. The presence of either of these mutation types has been associated with clinical response to tyrosine kinase inhibitor therapies (gefitinib and erlotinib). This fragment analysis test will detect EGFR exon 19 deletion mutations and the L858R mutation in formalin fixed paraffin-embedded blocks, unstained paraffin sections on slides, and fresh/frozen tissue. The submitted specimen should contain an adequate proportion of tumor cells (> 5%) to enable mutation detection.

Reference Range *

Interpretive report provided

Test Limitations

This test will not detect EGFR mutations other than exon 19 deletions and L858R and may fail to detect mutations below the limit of detection of this assay (approximately 5% mutant allele). Discordant results are rarely observed between metastatic and primary specimens.

Test Details
Days Set Up
Monday - Friday
Analytic Time

3 - 8 days

Soft Order Code
MiChart Code
EGFR Mutation by Fragment Analysis
Molecular Diagnostics
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) 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. Diff-Quik stained aspirate smears (preferable containing a high percentage and overall amount of neoplastic cells) are acceptable. Store at room temperature.

Normal Volume
Formalin-fixed, paraffin-embedded tissue; Diff-Quik 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 and federal laws and the clinician has authorization from the patient permitting MLabs to report the test results to the ordering clinician. This test includes a pathologist’s review and microdissection billed as a separate charge. This test also includes a pathologist’s interpretation of results billed as a separate additional charge. This test is not available without this interpretation.

CPT Code
81235, 88381-TC
Fee Code
21660, NA037
Pro Fee CPT
G0452-26, 88381-26
NY State Approved