Epidermal
Growth Factor Receptor (EGFR) Mutation Analysis
Clinical
Significance:
Recently
established guidelines from the American Society for Clinical Pathology (ASCP),
College of American Pathologists (CAP), Association for Molecular Pathology
(AMP), and/or the American Society of Clinical Oncology (ASCP) recommend
testing for all newly diagnosed non-small cell, non-squamous lung
carcinomas or such metastatic lung carcinomas that have not had a primary resection
available for testing. This test is
used to detect EGFR gene hotspot
mutations found in exons 18-19, 20 and 21, which include point mutations,
deletions and insertions. This testing allows identifying patients
who are most likely to respond to targeted lung cancer therapy, including
tyrosine kinase inhibitors (TKIs) erlotinib and gefitinib.
Specimen
Requirements and Collection:
Formalin-fixed tissue containing a sufficient amount of tumor (generally
at least several mm of tumor tissue submitted in the tissue block)
Methodology:
DNA isolation and extraction, library prep, and next-generation
sequencing (NGS)
Forms:
Molecular pathology requisition form
Transport:
Send formalin-fixed, paraffin-embedded (FFPE) tissue and cell block
containing tumor at room temperature.
Also acceptable 10-unstained, 4-5 micron slides with 1 post
H&E. Please include a surgical
pathology report
Unacceptable
specimen:
Specimens fixed in alternative fixatives or metal fixatives (ex. B-plus). Decalcified specimens.
Reference
Range:
EGFR mutation
present = positive result
EGFR mutation
not detected = negative result
CPT codes:
88381, 81235, G0452
Test
reported:
Results are reported within 7-10 days
