title: Pulmonary embolism in oncologic patients: frequency and embolus burden of symptomatic and unsuspected events.
abstract: BACKGROUND
  Pulmonary embolism (PE) is a common cause of morbidity and mortality in oncologic patients. Furthermore, PE is an unsuspected finding in many cases.
  
  
  OBJECTIVE
  To determine the frequency and embolus burden of PE in a consecutive oncologic patient group including symptomatic as well as incidental and initially unreported events.
  
  
  METHODS
  In a retrospective, single-center study from June 2005 to January 2010 all patients with an oncologic disease (ICD-10 code C00 to C96) that received at least one contrast-enhanced computed tomography (CT) examination of the chest were reviewed. The study group included 3270 patients with 6780 examinations. A validated pulmonary artery obstruction index (Mastora score) was used to assess embolus burden.
  
  
  RESULTS
  PE was found in 240 of 3270 (7.3%) oncologic patients. The frequency was highly variable among different malignancies ranging from 0% to 25%. In the present study about half of all PE were unsuspected. The mean embolus burden was significantly higher in symptomatic PE than in unsuspected PE (P <0.001). The risk of developing a PE was 1.5 times higher in patients with metastases compared to patients without metastases (P <0.005). Age and sex had no influence on PE risk and embolus burden.
  
  
  CONCLUSIONS
  PE is a frequent unsuspected finding in staging examinations: particularly in patients with malignancies of the ovary, brain, and pancreas, and in patients with metastases. Therefore, the status of the pulmonary vasculature should be assessed in every staging examination that includes the chest. The effect of therapeutic actions on PE events and the unsuspected finding of PE in follow-up CT examinations require further prospective studies.
authors.affiliation: Department of Radiology, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
authors.forename: Andreas Gunter
authors.initials: AG
authors.lastname: Bach
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Schmoll
authors.forename: Christoph
authors.initials: C
authors.lastname: Beckel
authors.forename: Curd
authors.initials: C
authors.lastname: Behrmann
authors.forename: Rolf Peter
authors.initials: RP
authors.lastname: Spielmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Wienke
authors.forename: Jasmin
authors.initials: J
authors.lastname: Abbas
authors.forename: Alexey
authors.initials: A
authors.lastname: Surov
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D006801:Humans; D007479:Iopamidol; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications*; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging* / Q000209:etiology*; D013902:Radiography, Thoracic; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007479:Iopamidol
keywords: CT staging incidental finding; Mastora score; Oncologic patients; malignancy; pulmonary angiography; unsuspected pulmonary embolism