title: D-dimer assay to exclude pulmonary embolism in high-risk oncologic population: correlation with CT pulmonary angiography in an urgent care setting.
abstract: OBJECTIVE
  To prospectively evaluate (a) the diagnostic performance of D-dimer assay for pulmonary embolism (PE) in an oncologic population by using computed tomographic (CT) pulmonary angiography as the reference standard, (b) the association between PE location and assay sensitivity, and (c) the association between assay results and clinical factors that raise suspicion of PE.
  
  
  METHODS
  This HIPAA-compliant study had institutional review board approval; informed consent was obtained. Five hundred thirty-one consecutive patients were clinically suspected of having PE; 201 were enrolled (72 men, 129 women; median age, 61 years) and underwent CT pulmonary angiography and D-dimer assay. Relevant clinical history, symptoms, and signs were recorded. CT images were interpreted, and the location of emboli was recorded. The negative predictive value (NPV), positive predictive value (PPV), sensitivity, specificity, and diagnostic likelihood ratios of the D-dimer assay results were calculated.
  
  
  RESULTS
  Forty-three patients (21%) had pulmonary emboli at CT. D-Dimer results were positive in 171 patents (85%). The NPV and sensitivity were 97% and 98%, respectively. The specificity and PPV were 18% and 25%, respectively. No association was shown between clinical history, symptoms, or signs and NPV, PPV, sensitivity, or specificity or between location of PE and sensitivity.
  
  
  CONCLUSIONS
  D-Dimer results have high NPV and sensitivity for PE in oncologic patients and, if negative, can be used to exclude PE in this population. Combining the assay with clinical symptoms and signs did not substantially change NPV, PPV, sensitivity, or specificity.
authors.affiliation: Department of Radiology, Department of Medicine, Urgent Care Service, Department of Epidemiology and Biostatistics, and Clinical Laboratories, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY 10021, USA.
authors.forename: Valencia
authors.initials: V
authors.lastname: King
authors.forename: Anjali A
authors.initials: AA
authors.lastname: Vaze
authors.forename: Chaya S
authors.initials: CS
authors.lastname: Moskowitz
authors.forename: Larry J
authors.initials: LJ
authors.lastname: Smith
authors.forename: Michelle S
authors.initials: MS
authors.lastname: Ginsberg
mesh_terms: D000328:Adult; D000792:Angiography / Q000379:methods*; D003287:Contrast Media; D004630:Emergencies; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D006801:Humans; D007472:Iohexol; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000097:blood* / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D; D007472:Iohexol