title: ALK expression is absent in pancreatic ductal adenocarcinoma.
abstract: OBJECTIVE
  It has not yet been clearly defined whether anaplastic lymphoma kinase (ALK) expression can be detected in pancreatic ductal adenocarcinoma (PDAC).
  
  
  METHODS
  Within a retrospective study, archival PDAC surgical specimens were screened for ALK expression in tumor and normal tissue by immunohistochemistry (IHC) with the use of a specific ALK detection kit on a tissue microarray (TMA).
  
  
  RESULTS
  PDAC tumor tissue was available from 99 resected cases: fifty-eight out of 99 patients (59 %) had nodal-positive disease, and 80 patients (81 %) had pT3 tumors. Forty-nine patients underwent R0 resection, and in 48 cases, resection status was classified R1. Regarding ALK expression, five cases showed faint immunoreactivity on TMA, which was negative on whole mount sections. All other 94 cases showed no ALK expression.
  
  
  CONCLUSIONS
  In 99 PDAC cases, no ALK expression was detected by IHC; ALK thus may not serve as a relevant drug target in PDAC.
authors.affiliation: Institute of Pathology, Ludwig-Maximilians-University of Munich, Thalkirchnerstr. 36, 80337, Munich, Germany, steffen.ormanns@med.uni-muenchen.de.
authors.forename: Steffen
authors.initials: S
authors.lastname: Ormanns
authors.forename: Gerald
authors.initials: G
authors.lastname: Assmann
authors.forename: Simone
authors.initials: S
authors.lastname: Reu
authors.forename: Eike
authors.initials: E
authors.lastname: Gallmeier
authors.forename: Dominik C
authors.initials: DC
authors.lastname: Bader
authors.forename: Axel
authors.initials: A
authors.lastname: Kleespies
authors.forename: Michael
authors.initials: M
authors.lastname: Haas
authors.forename: Stephan
authors.initials: S
authors.lastname: Kruger
authors.forename: Volker
authors.initials: V
authors.lastname: Heinemann
authors.forename: Thomas
authors.initials: T
authors.lastname: Kirchner
authors.forename: Stefan
authors.initials: S
authors.lastname: Boeck
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077548:Anaplastic Lymphoma Kinase; D021441:Carcinoma, Pancreatic Ductal / Q000235:genetics*; D005260:Female; D015870:Gene Expression / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000235:genetics*; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*; D012189:Retrospective Studies
chemical_list: C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D020794:Receptor Protein-Tyrosine Kinases