title: EGFR mutational genotyping of liquid based cytology samples obtained via fine needle aspiration (FNA) at endobronchial ultrasound of non-small cell lung cancer (NSCLC).
abstract: OBJECTIVE
  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.
  
  
  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.
  
  
  CONCLUSIONS
  ASPCR can reliably detect EGFR gene mutations in FNA preparations from patients with NSCLC obtained at EBUS.
authors.affiliation: Department of Molecular Pathology, Robert J. Tomsich Pathology & Laboratory Medicine Institute, Cleveland Clinic and the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States; Department of Anatomic Pathology, Robert J. Tomsich Pathology & Laboratory Medicine Institute, Cleveland Clinic and the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States. Electronic address: Reynolj4@ccf.org.
authors.forename: Jordan P
authors.initials: JP
authors.lastname: Reynolds
authors.affiliation: Department of Molecular Pathology, Robert J. Tomsich Pathology & Laboratory Medicine Institute, Cleveland Clinic and the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States.
authors.forename: Raymond R
authors.initials: RR
authors.lastname: Tubbs
authors.affiliation: Department of Molecular Pathology, Robert J. Tomsich Pathology & Laboratory Medicine Institute, Cleveland Clinic and the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States; Department of Anatomic Pathology, Robert J. Tomsich Pathology & Laboratory Medicine Institute, Cleveland Clinic and the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States.
authors.forename: Eugen C
authors.initials: EC
authors.lastname: Minca
authors.affiliation: Department of Molecular Pathology, Robert J. Tomsich Pathology & Laboratory Medicine Institute, Cleveland Clinic and the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States.
authors.forename: Stephen
authors.initials: S
authors.lastname: MacNamara
authors.affiliation: The Respiratory Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Francisco A
authors.initials: FA
authors.lastname: Almeida
authors.affiliation: Department of Solid Tumor Oncology, Taussig Cancer Center, Cleveland Clinic, United States.
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Ma
authors.affiliation: Department of Solid Tumor Oncology, Taussig Cancer Center, Cleveland Clinic, United States.
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Pennell
authors.affiliation: The Respiratory Institute, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Cicenia
mesh_terms: D000483:Alleles; D044963:Biopsy, Fine-Needle; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000235:genetics*; D019160:Endosonography; D066246:ErbB Receptors / Q000235:genetics*; D005091:Exons; D005787:Gene Frequency; D005838:Genotype; D060005:Genotyping Techniques; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000235:genetics*; D009154:Mutation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D066246:ErbB Receptors
keywords: Endobronchial ultrasound guided fine needle aspiration; Epidermal growth factor receptor; Fine needle aspiration; Lung cancer; Non-small cell lung carcinoma; Targeted therapy