Pleuroscopy First Versus Thoracentesis First in Patients With Suspected Malignant Pleural Effusions

This is a randomized control trial of patients with suspected malignant pleural effusions comparing patients who undergo either pleuroscopy or thoracentesis as the first diagnostic test. Both procedures are considered standard of care for this diagnosis but it is unknown which one provides more adequate biopsy samples and achieves faster diagnosis and shorter time to oncologic treatment. Currently, most patients undergo thoracentesis first and, if this is inadequate for diagnosis, they then undergo pleuroscopy for further biopsy samples. This study seeks to assess whether patients who undergo pleuroscopy as the first test obtain adequate biopsy samples and a faster path to further oncologic care compared to patients who undergo thoracentesis first. Patients will be recruited and randomized in a 1:1 manner.

Ultrasound is routinely used prior to the procedure and a chest x-ray is done after the procedure. Any other imaging will be determined by clinic need only. No imaging will be done for research purposes. No additional samples will be collected other than what is necessary for diagnostic purposes. In patients who have a non-diagnostic thoracentesis, the participants will be referred for pleuroscopy as the next diagnostic step. In the rare case that pleuroscopy does not achieve adequate diagnosis, the next step would be a liquid biopsy (non-invasive serologic testing for oncologic markers.) The need for liquid biopsy in participants in this study will be determined on a case-by-case basis depending on the clinical concern for malignancy.

Inclusion criteria

• Referral for diagnostic pleural procedure.
• Age ≥ 18 years.
• Suspected malignant pleural effusion (Suggestive radiologic appearance (based on computed tomography or positron emission tomography) OR suspected cancer with associated effusion.)

Exclusion criteria

• Inability to provide informed consent.
• Needs emergent drainage.
• Pleural effusion is known to be malignant.
• Suspected transudative, infectious or inflammatory effusion etiology.
• Having prior inconclusive/non-diagnostic thoracentesis or pleuroscopy.
• Patient is deemed by the clinical team to be more appropriate for VATS biopsy.
• Terminally ill patients in whom a diagnosis will not change management, or who is unlikely to be a candidate for oncological treatment due to significant comorbidities.
• Pregnancy