title: Standard pleural biopsy versus CT-guided cutting-needle biopsy for diagnosis of malignant disease in pleural effusions: a randomised controlled trial.
abstract: BACKGROUND
  Over 200000 pleural effusions are attributable to cancer in the UK and USA every year. Cytological examination of pleural fluid classifies about 60% of malignant effusions. Pleural biopsy needs to be done in the remaining cases. We aimed to assess whether CT-guided biopsy is an improvement over standard pleural biopsy in this setting.
  
  
  METHODS
  50 consecutive patients with cytologically negative suspected malignant pleural effusions were recruited. All had a contrast-enhanced thoracic CT scan to assess pleural thickening. Patients were randomly allocated, stratified by baseline pleural thickening, to either Abrams' pleural biopsy (standard care; n=25) or CT-guided cutting needle biopsy (n=25). Sensitivity for pleural malignancy from the biopsy specimen was the primary endpoint, with the patient's clinical outcome after 1 year being the diagnostic gold standard. Analysis was per protocol.
  
  
  RESULTS
  Three patients did not undergo biopsy. Abrams' biopsy correctly diagnosed malignancy in eight of 17 patients (sensitivity 47%, specificity 100%, negative predictive value 44%, positive predictive value 100%). CT-guided biopsy correctly diagnosed malignancy in 13 of 15 (sensitivity 87%, specificity 100%, negative predictive value 80%, positive predictive value 100%; difference in sensitivity between Abrams' and CT-guided 40%, 95% CI 10-69, p=0.02). Diagnostic advantage was similar in patients proving to have mesothelioma.
  
  
  CONCLUSIONS
  Primary use of CT-guided biopsy would avoid doing at least one Abrams' biopsy for every 2.5 CT-guided biopsies undertaken. In cytology-negative suspected malignant pleural effusions, CT-guided pleural biopsy is a better diagnostic test than Abrams' pleural biopsy.
authors.affiliation: Respiratory Trials Unit, Oxford Centre for Respiratory Medicine, Churchill Hospital, Oxford Radcliffe NHS Trust, OX3 7LJ, Oxford, UK. nickmaskell@doctors.org.uk <nickmaskell@doctors.org.uk>
authors.forename: N A
authors.initials: NA
authors.lastname: Maskell
authors.forename: F V
authors.initials: FV
authors.lastname: Gleeson
authors.forename: R J O
authors.initials: RJ
authors.lastname: Davies
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle / Q000295:instrumentation*; D002277:Carcinoma / Q000473:pathology; D003937:Diagnosis, Differential; D004739:England; D005260:Female; D006801:Humans; D008297:Male; D008654:Mesothelioma / Q000473:pathology*; D008875:Middle Aged; D016066:Pleural Effusion, Malignant / Q000473:pathology*; D010997:Pleural Neoplasms / Q000473:pathology*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*