Malignant peritoneal mesothelioma is a rare and aggressive cancer that develops in the lining around the abdominal organs. Doctors usually treat it with surgery and chemotherapy.

Peritoneal mesothelioma starts in the cells that make up the mesothelial lining of the abdominal cavity and typically spreads diffusely in the abdominal area.

Diffuse spread means that the edges of the tumor do not have clear borders between cancerous cells and noncancerous cells, making it hard to fully remove the tumor with surgery.

It develops when a mutation causes mesothelial tissue cells to divide rapidly.

Researchers are currently looking for improved treatment options for peritoneal mesothelioma. Current treatment involves removing as much of the tumor as possible, followed by chemotherapy to target any cells that may have been left behind.

Continue reading to learn about the possible causes of peritoneal mesothelioma, the possible symptoms, and how it’s treated.

Peritoneal mesothelioma develops in the mesothelial lining of the peritoneum, which is the lining around the abdominal organs.

Like other forms of mesothelioma, it may develop about 20 years after exposure to asbestos or other mineral fibers. However, the link to asbestos exposure isn’t as strong with peritoneal mesothelioma as with other forms.

Other risk factors that may increase the risk of developing peritoneal mesothelioma may include:

Peritoneal mesothelioma usually causes symptoms such as:

  • abdominal swelling due to fluid buildup
  • abdominal pain
  • diarrhea
  • constipation
  • nausea
  • unexplained weight loss

Your symptoms may vary depending on the location and size of the tumor.

To diagnose peritoneal mesothelioma, doctors may order imaging scans and other tests to determine the cause of your symptoms and rule out potential causes. This may include:

After a biopsy, experts analyze the removed tissue in a laboratory for the presence of specific cancer markers. This can provide your care team with information about the specific mutations of your peritoneal mesothelioma.

Treatment for peritoneal mesothelioma typically involves cytoreductive surgery (CRS) to remove as much of the tumor mass as possible from around the abdominal cavity.

This may be followed by hyperthermic intraperitoneal chemotherapy (HIPEC) to target any remaining cancer cells. HIPEC is also known as “hot” chemotherapy, as it involves heating the chemotherapy drugs.

Doctors perform HIPEC during surgery. They fill the abdomen with chemotherapy medication, which provides a more intense dose of chemotherapy compared to infused or oral chemotherapy. This may reduce chemotherapy side effects on the rest of the body.

However, the digestive system needs to recover after HIPEC, and people may need to receive a feeding tube or intravenous (IV) nutrition for about 2 weeks following the procedure.

If the cancer has spread beyond the abdomen, your care team may recommend infused chemotherapy to target it.

Clinical trials

You may also qualify for a clinical trial to treat peritoneal mesothelioma, particularly if you’ve already had surgery and HIPEC and the cancer comes back.

Clinical trials examine the effectiveness of new treatments or new combinations of treatment, such as:

  • additional chemotherapy
  • targeted therapies that may prevent the cancer cells from replicating by blocking certain proteins
  • targeted therapies that destroy cells with certain mutations

Peritoneal mesothelioma is a rare and aggressive cancer. However, a person’s individual outlook with it can depend on many factors, including:

  • age
  • specific mutations in the tumor
  • size and spread of the tumor
  • overall health
  • response to treatment

According to 2022 research based on data from 2015 to 2018, the median age-standardized survival is about 16.6 months. However, the same researchers note that CRS and HIPEC may improve a person’s outlook with peritoneal mesothelioma, in some cases to a median of 34 to 92 months.

If you have a diagnosis of peritoneal mesothelioma, it’s best to talk with your care team about your individual outlook.

Peritoneal mesothelioma is a rare cancer that develops in the lining around the abdominal organs.

Doctors usually treat it with surgery to remove cancerous cells followed by intensive chemotherapy to target any cells left behind after surgery.

Your specific treatment plan can depend on your overall health and where the tumor has spread.