title: Cytology specimens offer an effective alternative to formalin-fixed tissue as demonstrated by novel automated detection for ALK break-apart FISH testing and immunohistochemistry in lung adenocarcinoma.
abstract: BACKGROUND
  Minimally invasive sampling by cytology or core needle biopsy often provides an initial diagnosis for treatment in patients with lung nodules. From these limited specimens, multiple molecular studies are frequently requested. Current guidelines from the US Food and Drug Administration recommend using formalin-fixed paraffin-embedded tissue sections for the detection of anaplastic lymphoma kinase (ALK) gene rearrangement by fluorescence in situ hybridization (FISH). The authors compared alcohol-fixed and formalin-fixed cytology specimens using a novel automated detection for ALK rearrangements by FISH and immunohistochemistry (IHC).
  
  
  METHODS
  ALK FISH testing was performed on 129 lung adenocarcinomas from 71 cytology cases and 58 biopsy/resection specimens using Papanicolaou staining with integrated cytomorphology. IHC with the ALK D5F3 antibody was performed on cases with residual material (88 of 129 cases).
  
  
  RESULTS
  The mean age of the patients was 66 years; there were 62 women and 67 men. ALK gene rearrangement was present in 4% of cytology specimens (3 of 71 specimens) and 7% of surgical specimens (4 of 58 specimens). FISH in 13 cases was technically unsuccessful. Of the 7 FISH-positive cases, only 2 cytology cases (4%) and 2 surgical cases (6%) were found to be positive with the ALK antibody, demonstrating 80% concordance. The one case found to be negative for ALK by IHC demonstrated a variant rearrangement of the ALK 2p23 gene locus by FISH.
  
  
  CONCLUSIONS
  The results of the current study validate the usefulness of alcohol-fixed and/or formalin-fixed cytology specimens for ALK rearrangement by a novel automated FISH method. IHC using the D5F3 antibody for ALK is specific in this limited cohort. The authors also demonstrated that alcohol-fixed cytology specimens can be used for ALK rearrangement by automated FISH, alone or in conjunction with IHC.
authors.affiliation: Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Frida
authors.initials: F
authors.lastname: Rosenblum
authors.forename: Lloyd M
authors.initials: LM
authors.lastname: Hutchinson
authors.forename: Joann
authors.initials: J
authors.lastname: Garver
authors.forename: Bruce
authors.initials: B
authors.lastname: Woda
authors.forename: Ediz
authors.initials: E
authors.lastname: Cosar
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Kurian
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000438:Alcohols / Q000737:chemistry; D000077548:Anaplastic Lymphoma Kinase; D003581:Cytodiagnosis / Q000379:methods; D066246:ErbB Receptors / Q000235:genetics; D005260:Female; D005404:Fixatives / Q000737:chemistry*; D005557:Formaldehyde / Q000737:chemistry; D015321:Gene Rearrangement; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009154:Mutation; D065006:Papanicolaou Test / Q000379:methods; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016707:Tissue Fixation / Q000379:methods; D055815:Young Adult; D018631:ras Proteins / Q000235:genetics
chemical_list: D000438:Alcohols; D005404:Fixatives; D005557:Formaldehyde; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D066246:ErbB Receptors; D020794:Receptor Protein-Tyrosine Kinases; D018631:ras Proteins
keywords: ALK immunohistochemistry; anaplastic lymphoma kinase (ALK); crizotinib; fluorescence in situ hybridization (FISH); lung adenocarcinoma; lung cytology