title: Diagnostic value of a novel fully automated immunochemistry assay for detection of ALK rearrangement in primary lung adenocarcinoma.
abstract: BACKGROUND
  To evaluate the diagnostic value of a novel fully automated immunohistochemistry (IHC) assay for detection of anaplastic lymphoma kinase (ALK) fusion in a large number of ALK-positive lung adenocarcinoma (ADC) patients.
  
  
  METHODS
  We tested 196 lung ADCs for ALK rearrangement by two IHC assays (Ventana pre-diluted ALK D5F3 antibody with the Optiview DAB IHC detection kit and Optiview Amplification kit, D5F3 by Cell Signaling Technology (CST) with Ultraview DAB detection kit by Ventana), fluorescence in situ hybridization (FISH) and real-time reverse transcription-PCR (RT-PCR). CST ALK IHC was scored using the scoring scheme of 0, no staining; 1+, faint; 2+, moderate; and 3+, strong cytoplasmic reactivity in ≥ 10% of tumor cells. As for Ventana IHC, a binary scoring system (positive or negative for ALK status) was adopted for evaluating the staining results.
  
  
  RESULTS
  Among 196 cases tested, 63 (32%), 65 (33%), 70 (36%), and 69 (35%) cases were ALK positive by FISH, Ventana IHC, CST IHC, and RT-PCR, respectively. The sensitivity and specificity of Ventana IHC were 100% and 98%, respectively. Two Ventana IHC-positive cases, which were also CST IHC score of 3+, showed FISH negative, but their ALK rearrangement was confirmed by RT-PCR and direct sequencing. The sensitivity and specificity of CST IHC with staining intensity score of 1+ or more were 100% and 95%, respectively. Five (25%, of 20) patients with CST IHC score of 1+ were both FISH and RT-PCR negative. The sensitivity and specificity of RT-PCR for detection of ALK fusion were 98% and 95%, respectively. The total accordance rate between ALK RT-PCR and Ventana IHC was 97%.
  
  
  CONCLUSIONS
  The novel fully automated IHC assay is a reliable screening tool in routine pathologic laboratories for identification of patients with ALK rearrangement for targeted therapy in lung ADC.
authors.affiliation: Department of Pathology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China. Electronic address: jmying@hotmail.com.
authors.forename: J
authors.initials: J
authors.lastname: Ying
authors.affiliation: Department of Pathology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: L
authors.initials: L
authors.lastname: Guo
authors.affiliation: Department of Pathology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: T
authors.initials: T
authors.lastname: Qiu
authors.affiliation: Department of Pathology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: L
authors.initials: L
authors.lastname: Shan
authors.affiliation: Department of Pathology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Ling
authors.affiliation: Department of Pathology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Pathology, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: N
authors.initials: N
authors.lastname: Lu
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000235:genetics*; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077548:Anaplastic Lymphoma Kinase; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000235:genetics*; D005260:Female; D015321:Gene Rearrangement / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D017404:In Situ Hybridization, Fluorescence; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: D011993:Recombinant Fusion Proteins; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D020794:Receptor Protein-Tyrosine Kinases
keywords: ALK; fluorescence in situ hybridization; immunohistochemistry; lung cancer; targeted therapy