title: Tumour marker requesting in primary care and the role of the laboratory.
abstract: OBJECTIVE
  To review the incidence of multiple tumour marker (TM) requesting in the primary care setting and determine whether the rationale for requesting a TM panel is in agreement with evidence-based guidelines.
  
  
  METHODS
  Data-mining software was used to retrospectively identify multiple TM requests and requesting practices of GP surgeries over a 34-month period for α-fetoprotein, CA125, CA15-3, CA19-9, carcinoembryonic antigen and prostate-specific antigen. The appropriateness of each test was reviewed by a clinical biochemist in accordance with National Association of Clinical Biochemistry best-practice guidelines.
  
  
  RESULTS
  505 multiple TM requests were identified which corresponded to 1304 TM tests. Comparison with best-practice guidelines suggested that 68% of request cards contained no appropriate TM request, and 84% of the tests requested were inappropriate.
  
  
  CONCLUSIONS
  A review of requesting practices in primary care for TMs highlights the need for laboratories to be more proactive in educating their users on their clinical utility and limitations.
authors.affiliation: Department of Clinical Biochemistry, University Hospital Lewisham, London, UK. patrick.walker@gstt.nhs.uk
authors.forename: Patrick L C
authors.initials: PL
authors.lastname: Walker
authors.forename: Martin
authors.initials: M
authors.lastname: Crook
mesh_terms: D019985:Benchmarking; D014408:Biomarkers, Tumor / Q000032:analysis*; D019963:Clinical Chemistry Tests / Q000706:statistics & numerical data; D057225:Data Mining; D019317:Evidence-Based Medicine; D006801:Humans; D007400:Interprofessional Relations; D013677:Medical Laboratory Science / Q000706:statistics & numerical data*; D009369:Neoplasms / Q000097:blood / Q000175:diagnosis*; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D011320:Primary Health Care / Q000706:statistics & numerical data*; D012189:Retrospective Studies
chemical_list: D014408:Biomarkers, Tumor