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