title: Errors in cancer diagnosis: current understanding and future directions.
abstract: OBJECTIVE
  Errors in cancer diagnosis are likely the most harmful and expensive types of diagnostic errors. We reviewed the literature to understand the prevalence, origins, and prevention of errors in cancer diagnosis, focusing on common cancers for which early diagnosis offers clear benefit (melanoma and cancers of the breast, colon, and lung).
  
  
  METHODS
  We searched the Cochrane Library and PubMed from 1966 until April 2007 for publications that met our review criteria and manually searched references of key publications. Our search yielded 110 studies, of which nine were prospective studies and the remaining were retrospective studies.
  
  
  RESULTS
  Errors in cancer diagnosis were not uncommon in autopsy studies and were associated with significant harm and expense in malpractice claims. Literature on prevalence was scant. For each type of cancer, we classified preventable errors according to their origins in patient-physician encounters in the clinic setting, diagnostic test or procedure performance, pathologic confirmation of diagnosis, follow-up of patient or test result, or patient-related delays.
  
  
  CONCLUSIONS
  The literature reflects advanced knowledge of contributory factors and prevention for diagnostic errors related to the performance of procedures and imaging tests and emerging understanding of pathology errors. However, prospective studies are few, as are studies of diagnostic errors arising from the clinical encounter and patient follow-up. Future research should examine further the system and cognitive problems that lead to the many contributory factors we identified, and address interdisciplinary interventions to prevent errors in cancer diagnosis.
authors.affiliation: Health Policy and Quality Program, Houston Center for Quality of Care and Utilization Studies, Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX 77030, USA. hardeeps@bcm.tmc.edu
authors.forename: Hardeep
authors.initials: H
authors.lastname: Singh
authors.forename: Saurabh
authors.initials: S
authors.lastname: Sethi
authors.forename: Martin
authors.initials: M
authors.lastname: Raber
authors.forename: Laura A
authors.initials: LA
authors.lastname: Petersen
mesh_terms: D003951:Diagnostic Errors / Q000517:prevention & control* / Q000706:statistics & numerical data / Q000639:trends; D006801:Humans; D009369:Neoplasms / Q000175:diagnosis*; D015995:Prevalence; D011787:Quality of Health Care