title: Cytology smears as diagnostic material for EGFR gene testing in non-small cell lung cancer.
abstract: OBJECTIVE
  Cytology smears can be effectively used for EGFR mutation testing in the qualification of NSCLC patients for EGFR tyrosine kinase inhibitor therapy. However, tissue specimens are preferred for EGFR mutation analysis. The aim of this study was to estimate the effectiveness of the real-time PCR method for EGFR testing in histology and cytology materials obtained simultaneously from NSCLC patients.
  
  
  METHODS
  Fourteen adenocarcinoma patients with EGFR-mutation-positive primary tumor tissues were included in the study. Corresponding cytological smears of metastatic lymph nodes obtained by EBUS-TBNA were examined. EGFR Mutation Analysis Kit (EntroGen, USA) and real-time PCR (m2000rt system, Abbott, USA) were used for EGFR mutation analysis in both types of material.
  
  
  RESULTS
  In primary tumor tissues, 12 deletions in exon 19 and 2 substitutions in exon 21 (L858R mutation) of the EGFR gene were found. Except for 1 deletion in exon 19, the same EGFR gene mutations were detected in all corresponding cytology samples. The percentage of tumor cells, DNA concentration, percentage of mutated DNA as well as ΔCt values were similar in cytology slides and histology material. In both types of materials, no significant correlations were found between the percentage of tumor cells and the percentage of mutated DNA nor between the DNA concentration and the percentage of mutated DNA.
  
  
  CONCLUSIONS
  We demonstrated the high effectiveness of a sensitive real-time PCR method in EGFR gene mutation detection in cytology smears.
authors.affiliation: Pneumonology, Oncology and Allergology Department, Medical University, Lublin - Poland.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Powrózek
authors.affiliation: Pneumonology, Oncology and Allergology Department, Medical University, Lublin - Poland.
authors.forename: Paweł
authors.initials: P
authors.lastname: Krawczyk
authors.affiliation: Department of Pathology, Pulmonary Hospital, Zakopane - Poland.
authors.forename: Juliusz
authors.initials: J
authors.lastname: Pankowski
authors.affiliation: Genim Genetics and Immunology Institute, Lublin - Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Reszka
authors.affiliation: Department of Pathology, Pulmonary Hospital, Zakopane - Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Jakubiak
authors.affiliation: Department of Pathology, Pulmonary Hospital, Zakopane - Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Obrochta
authors.affiliation: Pneumonology, Oncology and Allergology Department, Medical University, Lublin - Poland.
authors.forename: Kamila
authors.initials: K
authors.lastname: Wojas-Krawczyk
authors.affiliation: Pneumonology, Oncology and Allergology Department, Medical University, Lublin - Poland.
authors.forename: Jarosław
authors.initials: J
authors.lastname: Buczkowski
authors.affiliation: Pneumonology, Oncology and Allergology Department, Medical University, Lublin - Poland.
authors.forename: Janusz
authors.initials: J
authors.lastname: Milanowski
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology*; D000368:Aged; D044963:Biopsy, Fine-Needle; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics; D003584:Cytological Techniques; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000032:analysis; D066246:ErbB Receptors / Q000235:genetics*; D005091:Exons; D005260:Female; D017353:Gene Deletion; D018773:Genes, erbB-1 / Q000235:genetics*; D005820:Genetic Testing; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009154:Mutation; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D004273:DNA, Neoplasm; C512478:EGFR protein, human; D066246:ErbB Receptors