title: Strategic management of transthoracic needle aspirates for histological subtyping and EGFR testing in patients with peripheral lung cancer: An institutional experience.
abstract: BACKGROUND
  Lung cancer therapy is personalized based on the histological subtype and molecular status. Totally, 70% of lung cancer patients present in advanced stages and are diagnosed on small biopsy or cytology specimens, hence an accurate but tissue-sparing approach is necessary. This study aimed to demonstrate efficient utilization of cell block (CB) on transthoracic needle aspiration (TTNA) for lung cancer subtyping, and to investigate the usefulness of needle washing after TTNA for assessing EGFR molecular status.
  
  
  METHODS
  Each TTNA specimen from the 79 peripheral lung masses was divided into three parts; liquid-based cytology (LBC), CB (with or without immunohistochemistry), and needle washing for analysis of EGFR mutation using peptide nucleic acid-mediated real-time PCR clamping.
  
  
  RESULTS
  Totally 79 specimens were diagnosed as malignancy, 75 (94.9%), benign, 3 (3.8%), and inadequate specimen, 1 (1.3%). The combination of LBC and CB (92.0%) showed a higher diagnostic yield for definitive subtyping of lung cancer than LBC alone (72.0%). Of the 75 malignant cases, 17 (22.7%) showed an EGFR mutation in needle washing specimens. EGFR mutational status was compared in all paired needle washing and scraped CBs with a 100% concordance.
  
  
  CONCLUSIONS
  We hereby proposed a strategy to maximize biological information retrieval from a limited TTNA specimen in patients with peripheral lung cancer. This algorithm indicated CB preparation for accurate histological subtyping and waste needle washing for molecular testing.
authors.affiliation: Department of Internal Medicine, Dong-A University College of Medicine, Busan, Korea.
authors.forename: Choonhee
authors.initials: C
authors.lastname: Son
authors.affiliation: Department of Radiology, Dong-A University College of Medicine, Busan, Korea.
authors.forename: Eun-Ju
authors.initials: EJ
authors.lastname: Kang
authors.affiliation: Department of Pathology, Dong-A University College of Medicine, Busan, Korea.
authors.forename: Mee Sook
authors.initials: MS
authors.lastname: Roh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics* / Q000378:metabolism; D044963:Biopsy, Fine-Needle / Q000379:methods; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology / Q000601:surgery; D066246:ErbB Receptors / Q000235:genetics* / Q000378:metabolism; D005091:Exons; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009154:Mutation; D020135:Peptide Nucleic Acids / Q000737:chemistry; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D014408:Biomarkers, Tumor; D020135:Peptide Nucleic Acids; C512478:EGFR protein, human; D066246:ErbB Receptors
keywords: EGFR; cell block; lung cancer; transthoracic needle aspiration