title: Antibody 1A4 with routine immunohistochemistry demonstrates high sensitivity for ALK rearrangement screening of Chinese lung adenocarcinoma patients: A single-center large-scale study.
abstract: OBJECTIVE
  The rearrangement of echinoderm microtubule-associated protein-like 4-analplastic lymphoma kinase (EML4-ALK) in non-small cell lung cancer (NSCLC) cells might be a promising therapeutic target. However, the low positive rate seeks a reliable and cost-effective method for ALK rearrangement prescreening. This study aimed to evaluate the application of a novel primary antibody 1A4 for routine ALK immunohistochemistry (IHC) test.
  
  
  METHODS
  Primary antibody 1A4 and D5F3 were used for the screening of 595 formalin-fixed, paraffin-embedded tissues of consecutive patients with lung adenocarcinoma for ALK-positive candidates. Ventana detection system and fluorescence in-situ hybridization (FISH) were used as reference methods.
  
  
  RESULTS
  Among 595 cases, the protein expression statuses of 1A4 were 3+ (18), 2+ (50), 1+ (153), and 0+ (374), and those of D5F3 were 3+ (17), 2+ (18), 1+ (20), and 0+ (540). Ventana detection system and FISH test results were successfully obtained from 482 cases. A total of 298 specimens with 1A4 (-) showed 100% concordance with standard FISH results. All 58 FISH (+) cases were identified by antibody 1A4. Meanwhile, 14 and 5 were missed by antibody D5F3 with routine IHC and Ventana system, respectively. 1A4 with routine IHC had better sensitivity (100%, 75.9%, and 91.4%, respectively), but lower specificity (70.3%, 99.8%, and 100%, respectively), than D5F3 with routine IHC and Ventana system.
  
  
  CONCLUSIONS
  The novel antibody 1A4 used as a prescreening method may help to reduce the false-negative rearranged ALK status if FISH or reverse transcription polymerase chain reaction results were used for validation.
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Qiushi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Lianhua
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Shirong
authors.initials: S
authors.lastname: Wei
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Chengyi
authors.initials: C
authors.lastname: Mao
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Li
authors.initials: L
authors.lastname: Lin
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Fu
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Lyu
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China.
authors.forename: Zengpeng
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Pathology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, 10# Changjiangzhilu, Daping, Yuzhong District, Chongqing 400042, China. Electronic address: dpbl_xhl@126.com.
authors.forename: Hualiang
authors.initials: H
authors.lastname: Xiao
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; D000906:Antibodies; D001706:Biopsy; D002681:China; D005260:Female; D015321:Gene Rearrangement; 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* / Q000378:metabolism; D012307:Risk Factors; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D000906:Antibodies; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D020794:Receptor Protein-Tyrosine Kinases
keywords: 1A4; ALK; D5F3; FISH; Immunohistochemistry; Lung adenocarcinoma