Peritoneal aspiration (drainage of fluid from the abdomen)

Peritoneal aspiration is a diagnostic test that takes a sample of fluid from the peritoneum to see if it contains cancer cells.

What is the peritoneum?

The organs in the tummy (abdomen) are covered by a lining (membrane) called the peritoneum. It has an inner and outer layer. The inner layer covers the organs in the abdomen. This is called the visceral peritoneum. The outer layer lines the abdominal wall. This is called the parietal peritoneum.

The peritoneum helps protect the organs in the abdomen and keeps them in place.

Mesothelioma can cause the layers of the peritoneum to thicken.

Side view of the tummy (abdomen) showing the peritoneum

A diagram of the side view of the tummy, showing the internal organs including the liver, stomach and bowel. Also shown is the peritoneum, the inner and outer layers, and the space between them called the peritoneal cavity. — Image: The illustration shows a side view of the tummy, which is also called the abdomen. The person is facing to the left. It shows the internal organs in the tummy, including the liver, the stomach and the bowel. These are surrounded by the peritoneum, which is a thin membrane. The peritoneum has two layers. The outer layer lines the wall of the tummy, and the inner layer covers the internal organs. There is a small space between these layers, called the peritoneal cavity.

What is peritoneal aspiration?

Mesothelioma cells can cause fluid to collect in the abdomen. This is called ascites. Your doctor may take a sample of this fluid to send to the laboratory. This is to see if it contains mesothelioma cells.

You may have an ultrasound scan during the test. Ultrasound uses sound waves to build up a picture of the area. This helps guide the doctor to where the fluid is. Your doctor will give you a local anaesthetic to numb the area first. After this, they pass a needle through your skin into the fluid to take a sample.

References

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

Kusamura S, Kepenekian V, Villeneuve L, Lurvink RJ, Govaerts K, De Hingh IHJT, Moran BJ, Van der Speeten K, Deraco M, Glehen O; PSOGI. Peritoneal mesothelioma: PSOGI/EURACAN clinical practice guidelines for diagnosis, treatment and follow-up. Eur J Surg Oncol. 2021 Vol, 47(1) pp6-59. [accessed April 2024].

Popat, S., Baas P., Faivre-Finn, C., Girard, N., Nicholson, A., Nowak, A., Opitz, I., Scherpereel, A, and Reck, M. 2021. ESMO Pleural mesothelioma guidelines. Malignant pleural mesothelioma: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Available from: https://www.annalsofoncology.org/action/showPdf [accessed April 2024].

Cancer Information Development team

Author

Dr David Gilligan

Reviewer

Consultant Clinical Oncologist

Addenbrookes Hospital, Cambridge

Date reviewed

Reviewed: 01 February 2025

Next review: 01 February 2028

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