Pleural effusion: transudates were rare with malignancy.

Clinical bottom line (level 4)

  1. Patients with malignancy rarely had transudative pleural effusions.
Assi et al: Chest 1998; 113 (5): 1302-1304
Expires October 2003

The study

Case series with objective outcomes, not adjusted for confounding factors, not validated in an independent set of patients.

Setting: university hospital, USA

98 patients (aged range 27 to 85 years; mean 62, 57% female) cytologically-proven malignant pleural effusions



Outcomes studied:
  • malignant effusions were exudates

    • Exudate defined according to Light's criteria: positive if any of:
      • pleural fluid LDH > two-thirds upper limit of normal serum level
      • pleural fluid: serum LDH ratio > 0.6
      • pleural fluid: serum protein ratio > 0.5

    The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)
    malignant effusions were exudates ? 97/98 99%
    (97% to 100%)

    • One patient had a borderline transudate and was in heart failure at the time. She had diffuse metastatic lung disease.

    Comments

    1. Few studies have assessed whether patients with malignancy only have exudates. Clinicians work on the assumption that a transudate makes malignancy unlikely though most centres perform routine cytology on pleural fluid samples.

    Citation

    1. Assi Z, Caruso JL, Herndon J, et al: cytologically proved malignant pleural effusions: distribution of transudates and exudates. Chest 1998; 113 (5): 1302-1304
    Contributor: Chris Ball and Clare Wotton, October 2000
    Reviewer:

    Clinical Question.
    Patient malignant pleural effusion
    Intervention or Exposure prevalence
    Outcome transudative effusions