title: Surfactant protein A detection in primary pulmonary adenocarcinoma without bronchioloalveolar pattern.
abstract: BACKGROUND
  Immunohistochemical studies in human lung carcinoma reported positive staining of tumor cells for surfactant protein A (SP-A), especially in peripheral airway cell carcinoma, which include bronchioloalveolar carcinoma and in some reports also papillary subtypes.
  
  
  OBJECTIVE
  The purpose of this study was to determine the SP-A expression in tumor cells of lung adenocarcinoma without a bronchioloalveolar pattern, classified according to the WHO.
  
  
  METHODS
  In total, 169 primary adenocarcinomas of the lung (109 acinar, 32 solid with mucin, 24 papillary and 4 mucinous) were examined by immunohistochemistry for SP-A expression.
  
  
  RESULTS
  Twenty-five percent of acinar, 38% of papillary and 3% of solid adenocarcinoma with mucin showed a positive intracytoplasmic SP-A reaction of the tumor cells. None of the mucinous adenocarcinomas stained for SP-A. This study included the largest number of acinar adenocarcinomas and solid adenocarcinomas with mucin studied for SP-A. We clearly demonstrated that also primary lung adenocarcinoma without a bronchioloalveolar pattern can express SP-A. A positive staining of hyperplastic type II cells surrounding the tumors or entrapped in the tumor could clearly be differentiated from the SP-A-positive stain of tumor cells.
  
  
  CONCLUSIONS
  These results support the theory that SP-A-producing cells may generate not only bronchioloalveolar and papillary carcinoma, but also other subtypes of lung adenocarcinoma.
authors.affiliation: General and Experimental Pathology, University of Bochum, Bochum, Germany.
authors.forename: Esra
authors.initials: E
authors.lastname: Uzaslan
authors.forename: Tina
authors.initials: T
authors.lastname: Stuempel
authors.forename: Michael
authors.initials: M
authors.lastname: Ebsen
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Freudenberg
authors.forename: Shinobu
authors.initials: S
authors.lastname: Nakamura
authors.forename: Ulrich
authors.initials: U
authors.lastname: Costabel
authors.forename: Josune
authors.initials: J
authors.lastname: Guzman
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D002288:Adenocarcinoma, Mucinous / Q000378:metabolism / Q000473:pathology; D000231:Adenocarcinoma, Papillary / Q000378:metabolism / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018267:Carcinoma, Acinar Cell / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology; D037662:Pulmonary Surfactant-Associated Protein A / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D037662:Pulmonary Surfactant-Associated Protein A