EGFR mutational genotyping of liquid based cytology samples obtained via fine needle aspiration (FNA) at endobronchial ultrasound of non-small cell lung cancer (NSCLC)

• Published in: Lung cancer (Amsterdam, Netherlands) Vol. 86; no. 2; pp. 158 - 163
• Main Authors: Reynolds, Jordan P., MD, Tubbs, Raymond R., DO, Minca, Eugen C., MD, PHD, MacNamara, Stephen, Almeida, Francisco A., MD, Ma, Patrick C., MD, Pennell, Nathan A., MD, PHD, Cicenia, Joseph C., MD
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ireland Ltd 01.11.2014; Elsevier
• Subjects: Alleles; Biological and medical sciences; Biopsy, Fine-Needle; Carcinoma, Non-Small-Cell Lung - diagnosis; Carcinoma, Non-Small-Cell Lung - genetics; Endobronchial ultrasound guided fine needle aspiration; Endosonography; Epidermal growth factor receptor; Exons; Fine needle aspiration; Gene Frequency; Genotype; Genotyping Techniques; Hematology, Oncology and Palliative Medicine; Humans; Lung cancer; Lung Neoplasms - diagnosis; Lung Neoplasms - genetics; Medical sciences; Multiple tumors. Solid tumors. Tumors in childhood (general aspects); Mutation; Non-small cell lung carcinoma; Pneumology; Pulmonary/Respiratory; Receptor, Epidermal Growth Factor - genetics; Reproducibility of Results; Sensitivity and Specificity; Targeted therapy; Tumors; Tumors of the respiratory system and mediastinum; ALK; NSCLC; Targeted therapy; Lung cancer; anaplastic lymphoma kinase; Non-small cell lung carcinoma; formalin-fixed paraffin-embedded; EBUS FNA; Epidermal growth factor receptor; EGFR; Fine needle aspiration; FFPE; cell block; ASPCR; allele specific polymerase chain reaction; Endobronchial ultrasound guided fine needle aspiration; CB; Lung disease; Typing; Respiratory disease; Sample; Cytology; Genotype; Malignant tumor; non-small cell lung carcinoma; Aspiration punction; Guidance; Liquid; Fine needle; Targeted drug; Bronchus disease; Mutation; Ultrasound; Cancer; Non small cell carcinoma
• ISSN: 0169-5002; 1872-8332
• DOI: 10.1016/j.lungcan.2014.09.003

Abstract Objectives Epidermal growth factor receptor ( EGFR ) gene mutation status should be determined in all patients with advanced, non-squamous non-small cell lung carcinoma (NSCLC) to guide targeted therapy with EGFR tyrosine kinase inhibitors. EGFR mutations are commonly tested by Sanger sequencing or allele specific polymerase chain reaction (ASPCR) on formalin-fixed paraffin-embedded (FFPE) samples including cell blocks (CB) that may fail due to absence of tumor cells. The cell pellet from cytology specimens obtained at the time of endobronchial guided ultrasound fine needle aspiration (EBUS FNA) (EBUS-TBNA, transbronchial needle aspiration) represents an alternative resource for additional tissue. Here we demonstrate the utility of using the FNA cell pellet versus for the detection of EGFR mutations in NSCLC. Materials and methods For internal validation, 39 cytology samples from patients with NSCLC referred for EGFR testing were analyzed using the EGFR rotor-gene Q (RGQ) PCR assay (Qiagen). Thereafter, a consecutive series of 228 EBUS FNA samples were tested. Results The ASPCR assay demonstrated acceptable intra-assay, inter-assay and inter-lot reproducibility, sensitivity, and specificity. For the consecutive series, only 6/228 (2.6%) failed analysis (5 due to insufficient DNA yield). Of 228 EBUS FNA cell pellets tested 32 (14.0%) demonstrated clinically relevant mutations. Results and conclusion ASPCR can reliably detect EGFR gene mutations in FNA preparations from patients with NSCLC obtained at EBUS.