Background:
Activating mutations in EGFR are present in approximately 10-12% of non-small cell carcinomas of the lung (primarily adenocarcinomas). Based on a number of phase II and III trials, most EGFR mutations predict a good response to treatment with EGFR inhibitors such as gefitinib and erlotinib.1 The exceptions are insertion mutations in exon 20 and the T790M substitution, which correlate with resistance to these drugs.
Methodology:
- Microscopic examination of the specimen and macrodissection of tumor-rich areas.
- DNA extraction and purification.
- PCR amplification of EGFR coding exons 18, 19, 20 & 21.
- Screening for mutations by one of two methods.
- Pyrosequencing of each exon
- Real-time PCR with high resolution melting curve analysis (HRM), to screen for deletions in exon 19 and insertions in exon 20. DNA sequencing is used to confirm any potential mutations identified by this approach.
- Estimated sensitivity: 20% mutant allele.
- Estimated specificity: 98% of EGFR mutations reported in non-small cell lung carcinoma.
Specimen Requirements:
- A paraffin block or
- 10 unstained sections of tumor (4-5 microns) (15 sections for small biopsies)
Contact Client Services for shipping materials and procedures at (855) 535-1522.
A REQUISITION FORM MUST ACCOMPANY ALL SAMPLES. Please include detailed clinical information.
Test Performed (Days):
Mon - Fri
Turn Around Time:
10-14 days
Shipment Sensitivity Requirements:
- Keep specimen cool during transit, but do not ship on dry ice.
- Please use the cold pack provided in the KDL shipping kit.
- Ship the specimen overnight express, using the FedEx priority overnight label provided.
- Contact Client Services for shipping materials and procedures at (855) 535-1522.
References:
- Linardou H, Dahabreh IJ, Bafaloukos D, Kosmidis P, Murray S. Somatic EGFR mutations and efficacy of tyrosine kinase inhibitors in NSCLC. Nat Rev Clin Oncol. 2009 Jun;6(6):352-66.
Additional Info: