Pleural aspiration (drainage of fluid from the pleura)

The pleura makes a fluid that acts as a lubricant. Your specialist doctor may take a sample of this fluid, to see if it contains cancer cells.

What is pleura?

The lungs are covered by a lining (membrane) called the pleura, which has 2 layers. Between the 2 layers, in a space called the pleural cavity, is a small amount of fluid. This fluid acts as a lubricant. It allows the lungs to move in and out smoothly and helps you to breathe easily.

What is a pleural aspiration?

Mesothelioma cells can cause fluid to build up between the 2 layers of the pleura around the lung. This is called a pleural effusion. Draining the fluid may help with your breathing. This is called a pleural aspiration. Your specialist doctor may take a sample of this fluid to be checked for mesothelioma cells.

About our information

  • References

    Below is a sample of the sources used in our mesothelioma information. If you would like more information about the sources we use, please contact us at

    Woolhouse I et al. British Thoracic Society Guideline for the investigation and management of malignant pleural mesothelioma. Thorax. 2018.

    Thomas A et al. Mesothelioma. BMJ Best Practice. 2019.

    Baas P et al. Malignant pleural mesothelioma: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up.  Annals of Oncology. 26 (Supplement 5): v31–v39. 2015. Available from:

    Kusamara S et al. Peritoneal mesothelioma: PSOGI/EURACAN clinical practice guidelines for diagnosis, treatment and follow-up. European Journal of Surgical Oncology. March 2020.

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Dr David Gilligan, Consultant Clinical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

Date reviewed

Reviewed: 01 August 2021
Next review: 01 August 2024
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

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