title: Bronchioloalveolar carcinoma: a review of current concepts and evolving issues.
abstract: BACKGROUND
  The concept of bronchioloalveolar carcinoma underwent considerable refinement between the publications of the 1981 and 1999 World Health Organization classifications of lung tumors. Both pathologic and clinical aspects of this carcinoma are the subject of considerable interest.
  
  
  OBJECTIVE
  To review and summarize the evolution of the current concept of bronchioloalveolar carcinoma and evolving issues that are under further investigation.
  
  
  METHODS
  Pertinent peer-reviewed literature emphasizing historical classification and evolution as well as current and evolving concepts.
  
  
  CONCLUSIONS
  Small, solitary, nonmucinous bronchioloalveolar carcinomas are associated with a markedly better prognosis compared with conventional invasive adenocarcinomas. Such tumors may be cured by surgical resection and may be more responsive to epidermal growth factor receptor-targeted therapy. The prognosis and staging of multifocal disease remain unresolved, as does the question of whether a small amount of invasion adversely affects prognosis. Mucinous bronchioloalveolar carcinoma appears to be a markedly different entity than the nonmucinous subtype.
authors.affiliation: Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: Samuel A
authors.initials: SA
authors.lastname: Yousem
authors.forename: Mary Beth
authors.initials: MB
authors.lastname: Beasley
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology; D002282:Adenocarcinoma, Bronchiolo-Alveolar / Q000737:chemistry / Q000145:classification / Q000473:pathology*; D004268:DNA-Binding Proteins / Q000032:analysis; D006801:Humans; D006965:Hyperplasia; D053552:Keratin-7 / Q000032:analysis; D008175:Lung Neoplasms / Q000737:chemistry / Q000473:pathology*; D011230:Precancerous Conditions / Q000473:pathology; D014157:Transcription Factors
chemical_list: D004268:DNA-Binding Proteins; D053552:Keratin-7; C504003:TTF1 protein, human; D014157:Transcription Factors