Table 2 Method of final diagnosis
Diagnostic methodNo of patients
Malignant disease (n = 33)
    Pleural histology:14
        Percutaneous biopsy10
        Thoracoscopic biopsy4
    Other histology:5
        Supraclavicular lymph node biopsy2
        Axillary lymph node biopsy1
    Pleural fluid cytology:11
    Clinical follow-up and repeat radiology3
Benign disease* (n = 19)
    Pleural histology†:6
        Percutaneous biopsy4
        Thoracoscopic biopsy2
    Other histology:3
        Supraclavicular lymph node biopsy2
    Pleural fluid cytology negative10
  • Pleural fluid cytology was taken as confirmation of malignancy only in the presence of a confident histopathology opinion reporting confirmed malignant cells on cytology ± immunostaining as required. In these cases, no further investigation to establish diagnosis was required. Negative pleural fluid cytology was not taken as definitive proof of benign aetiology (hence clinical follow-up as below was pursued).

  • *All patients with a diagnosis of benign disease were followed up for a period of 12 months (at our institution or the referring institution), in which time there was no evidence of malignancy developing within the pleura or elsewhere as the cause of the presenting pleural effusion.

  • †Two patients underwent non-diagnostic percutaneous pleural biopsy and subsequent diagnostic thoracoscopy. These patients are only listed once as thoracoscopic biopsies.