title: HER2 Testing and Clinical Decision Making in Gastroesophageal Adenocarcinoma: Guideline From the College of American Pathologists, American Society for Clinical Pathology, and American Society of Clinical Oncology.
abstract: BACKGROUND
  ERBB2 (erb-b2 receptor tyrosine kinase 2 or HER2) is currently the only biomarker established for selection of a specific therapy for patients with advanced gastroesophageal adenocarcinoma (GEA). However, there are no comprehensive guidelines for the assessment of HER2 in patients with GEA.
  
  
  OBJECTIVE
  To establish an evidence-based guideline for HER2 testing in patients with GEA, to formalize the algorithms for methods to improve the accuracy of HER2 testing while addressing which patients and tumor specimens are appropriate, and to provide guidance on clinical decision making.
  
  
  METHODS
  The College of American Pathologists, American Society for Clinical Pathology, and American Society of Clinical Oncology convened an expert panel to conduct a systematic review of the literature to develop an evidence-based guideline with recommendations for optimal HER2 testing in patients with GEA.
  
  
  RESULTS
  The panel is proposing 11 recommendations with strong agreement from the open-comment participants.
  
  
  CONCLUSIONS
  The panel recommends that tumor specimen(s) from all patients with advanced GEA, who are candidates for HER2-targeted therapy, should be assessed for HER2 status before the initiation of HER2-targeted therapy. Clinicians should offer combination chemotherapy and a HER2-targeted agent as initial therapy for all patients with HER2-positive advanced GEA. For pathologists, guidance is provided for morphologic selection of neoplastic tissue, testing algorithms, scoring methods, interpretation and reporting of results, and laboratory quality assurance.
  
  
  CONCLUSIONS
  This guideline provides specific recommendations for assessment of HER2 in patients with advanced GEA while addressing pertinent technical issues and clinical implications of the results.
authors.affiliation: From the Department of Pathology, St Joseph Mercy Hospital, Ann Arbor, MI angelbart16@gmail.com.
authors.forename: Angela N
authors.initials: AN
authors.lastname: Bartley
authors.affiliation: Department of Pathology, Vanderbilt University Medical Center, Nashville, TN.
authors.forename: Mary Kay
authors.initials: MK
authors.lastname: Washington
authors.affiliation: Surveys and Governance, College of American Pathologists, Northfield, IL.
authors.forename: Christina B
authors.initials: CB
authors.lastname: Ventura
authors.affiliation: Quality and Guidelines Department, American Society of Clinical Oncology, Alexandria, VA.
authors.forename: Nofisat
authors.initials: N
authors.lastname: Ismaila
authors.affiliation: Surveys and Governance, College of American Pathologists, Northfield, IL.
authors.forename: Carol
authors.initials: C
authors.lastname: Colasacco
authors.affiliation: Division of Hematology/Oncology, Northwestern University, Chicago, IL.
authors.forename: Al B
authors.initials: AB
authors.lastname: Benson
authors.affiliation: Medical Oncology Department, Ramon y Cajal University Hospital, Madrid, Spain.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Carrato
authors.affiliation: Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill.
authors.forename: Margaret L
authors.initials: ML
authors.lastname: Gulley
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, CT.
authors.forename: Dhanpat
authors.initials: D
authors.lastname: Jain
authors.affiliation: Department of Pathology and Laboratory Medicine, UCSF, San Francisco, CA.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Kakar
authors.affiliation: Division of Medical Oncology and Hematology, University of Toronto/Sunnybrook Odette Cancer Centre, Toronto, Canada.
authors.forename: Helen J
authors.initials: HJ
authors.lastname: Mackay
authors.affiliation: Department of Laboratory Medicine, St Michael's Hospital, Toronto, Canada.
authors.forename: Catherine
authors.initials: C
authors.lastname: Streutker
authors.affiliation: Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY.
authors.forename: Laura
authors.initials: L
authors.lastname: Tang
authors.affiliation: Department of Pathology, Stanford University Medical Center, Stanford, CA.
authors.forename: Megan
authors.initials: M
authors.lastname: Troxell
authors.affiliation: Department of Gastrointestinal Medical Oncology, University of Texas MD Anderson Cancer Center, Houston.
authors.forename: Jaffer A
authors.initials: JA
authors.lastname: Ajani
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D000970:Antineoplastic Agents / Q000627:therapeutic use; D000066491:Clinical Decision-Making; D004938:Esophageal Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D004943:Esophagogastric Junction / Q000473:pathology*; D005820:Genetic Testing; D006801:Humans; D008495:Medical Oncology; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D014481:United States
chemical_list: D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human
keywords: Gastroesophageal adenocarcinoma; Guidelines; HER2 testing