What Is Peritoneal Mesothelioma?

Peritoneal mesothelioma is a rare cancer that affects the peritoneum, the lining of the abdomen. It is also known as abdominal mesothelioma. As tumors develop and grow on the peritoneum, they put pressure on vital organs and can spread to form new tumors.

Approximately 10% to 17% of all mesothelioma diagnoses are peritoneal. Among respondents to our exclusive 2023 survey, 23% had been diagnosed with peritoneal mesothelioma. Of the estimated 1.9 million new cancer diagnoses each year in the U.S., only 300 to 500 are abdominal mesothelioma cases. 


Percentage of peritoneal mesothelioma diagnoses among respondents to The Mesothelioma Center’s 2023 mesothelioma patient survey.

Symptoms of Peritoneal Mesothelioma

Peritoneal mesothelioma signs and symptoms can include stomach pain, swelling, fever and unexplained weight loss. Abdominal pain and bloating are the most common first signs. Symptoms often appear 20 to 60 years after asbestos exposure and once the cancer has already progressed to a later stage. 

If you or a loved one has a history of asbestos exposure, it’s important to discuss this with your doctor. They may recommend regular screenings for mesothelioma and other asbestos-related conditions to help identify disease early.

Common Peritoneal Mesothelioma Symptoms
  • Abdominal pain and swelling
  • Anemia
  • Bowel obstruction
  • Changes in bowel habits
  • Chest pain
  • Difficulty breathing
  • Fatigue and weakness
  • Fever
  • Fluid buildup in the abdomen (ascites or peritoneal effusion)
  • Loss of appetite
  • Nausea and vomiting
  • Night sweats
  • Unexplained weight loss

Peritoneal mesothelioma shares common symptoms with many other abdominal cancers and disorders. An accurate diagnosis often requires a mesothelioma specialist with experience diagnosing and treating mesothelioma. 

Key Facts About Peritoneal Mesothelioma
  • Incidence among men and women is equal in peritoneal cases.
  • The 5-year survival rate for all cases of peritoneal mesothelioma is 65%.
  • More than 50% of peritoneal patients who undergo surgery with HIPEC live more than 5 years.
  • About 75% of patients who undergo surgery with post-operative and long-term chemotherapy live longer than 5 years.

Rare Symptoms of Peritoneal Mesothelioma

Peritoneal mesothelioma can spread or metastasize when it progresses, leading to rare and serious symptoms in other areas of your body. You may develop other symptoms if tumors spread to organs in the abdominal cavity, including the liver or intestines. 

Peritoneal metastasis typically remains local or near where the tumors originally formed. Distant metastases are rarer, occurring in 10% to 50% of stage 4 mesothelioma cases. When distant metastasis does occur, it can cause symptoms in other organs including the chest cavity and brain.

Rare Peritoneal Mesothelioma Symptoms
  • Abnormal liver function tests
  • Anemia
  • Blood clotting disorders
  • Bowel obstruction
  • Fluid buildup around the lungs (pleural effusions)
  • Fluid buildup in the sac surrounding the heart (pericardial effusion)
  • Hernias
  • High platelet count (thrombocytosis)
  • Jaundice
  • Low blood sugar (hypoglycemia)
  • Neurological symptoms such as seizures or paralysis

Serious but less common symptoms of peritoneal mesothelioma can be mistaken for another cancer, such as colon cancer. In our exclusive mesothelioma survey in 2023, peritoneal respondents cited anemia and bowel obstruction as serious symptoms.

No symptoms are unique to mesothelioma, making it difficult sometimes to determine why you may be experiencing them. Communicating your known history of asbestos exposure with your doctor can help raise suspicion of possible mesothelioma.

What Causes Peritoneal Mesothelioma?

Asbestos exposure is the primary cause of developing peritoneal mesothelioma. Inhaled asbestos fibers can travel through your bloodstream and into the abdomen. The fibers can become trapped and cause inflammation, irritation and DNA damage. This can lead to abnormal cell growth, causing tumors to form.

Mesothelioma takes decades to develop after initial asbestos exposure. Symptoms typically appear about 40 years after exposure.

An illustration that depicts how peritoneal mesothelioma develops from asbestos fibers.

Risk factors for mesothelioma include different types of asbestos exposure, including occupational, environmental and secondary exposure. Many mesothelioma survivors were exposed while serving in the U.S. armed forces. Asbestos exposure is the primary cause of other types of mesothelioma as well. 

How Is Peritoneal Mesothelioma Diagnosed?

Peritoneal mesothelioma is diagnosed with a core needle biopsy or laparoscopic biopsy. A biopsy, or tissue sample, is the only way to confirm the presence of malignant mesothelioma cells. 

A core needle biopsy uses a long needle inserted through your skin to collect a sample of cells from a suspected tumor. A laparoscopic biopsy involves inserting a camera and surgical instruments into the abdomen through small incisions to see inside your body and collect a tissue sample.

Collecting a sample of mesothelioma cells is essential for a proper diagnosis. Pathologists examine biopsies in a lab to identify types of cancer cells, including epithelioid, sarcomatoid and biphasic mesothelioma cell types. This information helps doctors select appropriate treatment options.

Blood tests and imaging scans are also used to help diagnose peritoneal mesothelioma. Scans are especially useful to identify tumors that have spread to nearby or distant locations in the body. The size, location and spread of tumor cells are all important for mesothelioma staging.

Why Peritoneal Mesothelioma Is Frequently Misdiagnosed

Because peritoneal mesothelioma is so rare, most doctors and even oncologists have never seen patients with mesothelioma. As peritoneal mesothelioma survivor Sara B. told The Mesothelioma Center, “My primary care doctor told me he had never seen anyone with this disease before in his career.”

Sharing common symptoms with other diseases such as the flu and other forms of cancer also increases the risk of an initial misdiagnosis. As peritoneal cancer survivor Tamron Little told The Mesothelioma Center, “I was nauseous. I was tired all the time. It was the same symptoms I had when I was pregnant.”

I was told I had a fibroid tumor when I was pregnant. Even after my pregnancy, I was still told I had a fibroid tumor. I had surgery to remove it because of its increasing size. It wasn’t a fibroid. It was peritoneal mesothelioma.

Malignant peritoneal mesothelioma misdiagnosis can delay your treatment. The best way to get a proper diagnosis is to schedule an appointment with a mesothelioma specialist. Peritoneal specialists have the experience to ensure you get an accurate diagnosis.

Your mesothelioma diagnostic process may seem overwhelming because of the number of tests, unfamiliar terms and procedures. A mesothelioma specialist understands this and will guide you and your loved ones through the diagnostic experience.

Survivor Story
Survivor Story
Tammy Frank Peritoneal mesothelioma

20-Year Peritoneal Mesothelioma Survivor Was First Misdiagnosed With an Ovarian Cyst

Tammy Frank was told an ovarian cyst was causing her abdominal pain. Surgery uncovered a much more serious problem. At the time, not many doctors could identify peritoneal mesothelioma. It took months and multiple tests to confirm. Her prognosis was grim. “I spend most of my time now helping others,” Tammy says. “I never, ever thought I’d still be here 20 years later.”

Read Tammy’s Story

Staging Peritoneal Mesothelioma

There is no official staging system for peritoneal mesothelioma, so doctors use more general cancer staging to determine the disease’s progress. Doctors often use the tumor, node, metastasis system, the most widely used cancer staging system, to define 3 stages of peritoneal mesothelioma.  

Using the TNM system, the stages of malignant peritoneal mesothelioma describe the size and location of tumors and how far they’ve spread in the body. Most peritoneal patients are diagnosed at a later stage. The stage of cancer affects treatment options and helps in assessing a patient’s prognosis.

Tumor spread determines stage of peritoneal mesothelioma

Stage 1 of Peritoneal Mesothelioma

In early-stage peritoneal mesothelioma or stage 1, cancerous tissue is minimal. Tumors are only within the abdominal lining and lymph nodes are free of cancer.

Stage 2 of Peritoneal Mesothelioma

In mid-stage peritoneal mesothelioma or stage 2, cancerous tissue is moderate. Tumors haven’t spread outside the lining or into lymph nodes.

Stage 3 of Peritoneal Mesothelioma

In late-stage mesothelioma or stage 3, cancerous tissue is more extensive. Tumors may have spread outside the peritoneal lining or into lymph nodes.

Stage 4 peritoneal mesothelioma isn’t clearly defined. Many doctors consider mesothelioma progression stage 4 when tumor spread is extensive and to distant sites throughout the body. 

The peritoneal cancer index is another tool doctors use to assess tumor cells and help determine the approximate mesothelioma stage and appropriate treatments. PCI scores range from 1 to 39. Lower index scores mean the patient may qualify for surgery, while index scores above 20 indicate that cancer has spread too far and the patient likely won’t respond well to surgery.

Peritoneal Mesothelioma Treatment

Chemotherapy is the most common treatment for peritoneal mesothelioma. The most effective treatment option is a multimodal therapy approach that incorporates cytoreductive surgery to remove tumors and hyperthermic intraperitoneal chemotherapy (HIPEC). HIPEC involves a multidisciplinary team of surgical oncologists, medical oncologists and other experts. Not all malignant peritoneal mesothelioma patients qualify for this procedure.

The treatment options your doctor recommends for you will depend on your stage, tumor cell type and overall health. Other common peritoneal mesothelioma treatment options include immunotherapy and surgery. Enrolling in a clinical trial can also give mesothelioma patients access to the latest treatment regimens and innovative new therapies. 

Chemotherapy for Peritoneal Mesothelioma

Patients who aren’t good candidates for HIPEC with surgery can undergo chemotherapy as a standalone therapy. Chemotherapy delivered throughout the bloodstream is called systemic, while delivery to the abdominal cavity is called localized.

Systemic chemotherapy has a response rate of about 30%. Chemotherapy delivered directly to the peritoneum without surgery has a higher response rate of 47%.

Chemotherapy Key Facts
  • Average progression-free survival is about 11.5 months.
  • Median survival is around 13 months.

Chemotherapy drugs are effective for shrinking peritoneal mesothelioma tumors and slowing the growth and spread of cancer. The effective chemotherapy drugs for peritoneal mesothelioma include carboplatin, cisplatin, gemcitabine, paclitaxel and pemetrexed.

HIPEC Surgery

Doctors perform cytoreductive surgery, called a peritonectomy, to remove as much cancer as possible from the abdominal cavity. Then they infuse heated chemotherapy into the abdomen before the surgery ends. Heating chemotherapy and applying it after surgery increases the chemotherapy response rate to 84.6%.

HIPEC surgery has shown significant promise in treating peritoneal mesothelioma patients. A recent study in the Journal of Clinical Haematology reported that more than 80% of the patients who underwent HIPEC and continued localized chemotherapy lived 5 years or longer.


Percentage of eligible patients among respondents to The Mesothelioma Center’s 2023 survey who underwent HIPEC surgery.

Doctors only perform this procedure on a case-by-case basis. HIPEC surgery is typically the recommendation only for younger patients in good enough overall health to tolerate the intensive 12-hour procedure and recovery. About 54% of peritoneal mesothelioma patients who responded to The Mesothelioma Center at Asbestos.com’s survey were eligible for HIPEC surgery. 

Peritoneal mesothelioma patients I speak with commonly ask about the HIPEC procedure. We can help answer their questions and match them to specialists who can assess if it’s the right treatment for them.

Peritoneal Mesothelioma Immunotherapy 

Immunotherapy uses drugs that help the body’s immune system fight cancer. Because peritoneal mesothelioma is so rare, data from clinical trials is limited. Research has produced mixed results, but some studies indicate that immunotherapy may be useful in some cases of peritoneal mesothelioma. 

The U.S. Food and Drug Administration hasn’t yet approved immunotherapy for peritoneal mesothelioma. The agency has approved it to treat pleural mesothelioma.

Palliative Care for Peritoneal Mesothelioma

Many peritoneal mesothelioma patients receive palliative care to control symptoms and improve their quality of life. Palliative care can include procedures to reduce pain and other symptoms. This includes draining excess fluid from the abdomen (paracentesis), HIPEC and surgery designed to reduce symptoms.

Palliative care specialists can prescribe medications to control pain and mesothelioma complications. They may also refer you to physical or occupational therapy or recommend complementary therapies to improve quality of life.

Peritoneal Mesothelioma Survival Rate and Prognosis

The prognosis for peritoneal mesothelioma is generally poor for patients who don’t qualify for surgery, which can significantly improve survival. For example, more than 50% of peritoneal patients who undergo surgery with HIPEC live more than 5 years. Those who undergo HIPEC, post-operative chemotherapy and long-term chemotherapy have a 5-year survival rate of 75%.

Everyone is different. No one can simply look at a diagnosis of mesothelioma and tell you what your life expectancy is.

Individual peritoneal mesothelioma prognosis and survival varies depending on several factors. These include the stage at which the cancer is detected, the specific mesothelioma cell type you have, the treatments they choose in consultation with their doctor, any coexisting conditions they may have and their overall health. 

Peritoneal mesothelioma survivors are now living longer than ever before. Statistics do show, however, that the average life expectancy of peritoneal mesothelioma without any treatment is only 6 months. People who don’t qualify for surgery live about 13 months with chemotherapy alone.

Finding Top Peritoneal Mesothelioma Specialists

Peritoneal mesothelioma is rare and difficult to treat, so it’s important you find care from an experienced mesothelioma specialist. In selecting top mesothelioma doctors to feature, The Mesothelioma Center rigorously vets specialists. 

We look for doctors who practice at the top cancer centers in the U.S. and have experience in working in multidisciplinary teams. Their research and publications in medical journals are also reviewed.

Dr. W. Charles Conway

Santa Barbara, California

W. Charles Conway

Peritoneal Specialist | Peritoneal Surface Malignancies

Expertise: Peritoneal Mesothelioma, Thoracic Diseases, Cytoreductive Surgery and HIPEC

Languages: English

Dr. J.F. Pingpank Jr., peritoneal mesothelioma doctor

Pittsburgh, Pennsylvania

J.F. Pingpank Jr.

Peritoneal Specialist | Surgical Oncology

Expertise: HIPEC Research

Languages: English

Dr. Hedy Lee Kindler, pleural mesothelioma doctor

Chicago, Illinois

Hedy Lee Kindler

Peritoneal Specialist | Gastrointestinal Oncology

Expertise: Immunotherapy Research

Languages: English

Dr. Sophie Dessureault, peritoneal mesothelioma doctor

Tampa, Florida

Sophie Dessureault

Peritoneal Specialist | Surgery

Expertise: Cytoreductive Surgery HIPEC

Languages: English, French

Dr. Mecker Moller, peritoneal mesothelioma specialist

Chicago, Illinois

Mecker Moller

Peritoneal Specialist | Surgical Oncology

Expertise: Cytoreductive Surgery HIPEC

Languages: English, Spanish

Dr. Daniel M. Labow, peritoneal mesothelioma specialist

Danbury, Connecticut

Daniel M. Labow

Peritoneal Specialist | Surgical Oncology

Expertise: Cytoreductive Surgery HIPEC

Languages: English

Cancer hospitals with a mesothelioma treatment center offer mesothelioma specialists and an experienced multidisciplinary treatment team. They also offer mesothelioma clinical trials and a full range of support services for patients and their families. 

Experience matters when treating mesothelioma. However, few doctors and hospitals have experience treating peritoneal mesothelioma. It’s important you try to find a top treatment center to ensure you have the best possible outcomes.

Common Questions About Peritoneal Mesothelioma

Is there a cure for peritoneal mesothelioma?

Unfortunately, there is currently no cure for peritoneal mesothelioma or any other type of mesothelioma yet. Research is ongoing to find better, more effective treatments.

Currently, HIPEC with cytoreductive surgery offers the best outcomes, increasing lifespan more than 5 years. Research has shown that combining HIPEC, post-operative chemotherapy and long-term chemotherapy works best. About 75% of these patients lived longer than 5 years.

Why is early detection of peritoneal mesothelioma important?

Early detection of mesothelioma has a significant impact on treatment outcomes and an increased chance of long-term survival. People with a history of asbestos exposure who show signs of the disease should seek an experienced peritoneal mesothelioma specialist.

How long can you live with peritoneal mesothelioma?

Life expectancy with peritoneal mesothelioma varies from person to person. Without treatment, median survival is 6 months. However, the overall 5-year survival rate for peritoneal mesothelioma is 65%. This percentage increases to 75% with surgery, HIPEC, post-operative chemotherapy and long-term chemotherapy.

Some peritoneal mesothelioma survivors have lived for decades after treatment — well beyond the average life expectancy. With ongoing research into new emerging treatments, experts predict the life expectancy for this cancer to increase.

Can peritoneal mesothelioma go into remission?

Yes, according to a 2020 study, about 12% of peritoneal mesothelioma patients who undergo aggressive treatment experience complete remission. Partial remission is also possible.

Remission isn’t the same as a cure. Doctors continue to monitor patients because cancer can return after entering partial or complete remission.

Are there tips for managing a peritoneal mesothelioma diagnosis?

Managing a cancer diagnosis is a challenging experience for patients and their loved ones. There is no one right way for you to cope with mesothelioma. Every individual experience is different.

Tips for Managing a Cancer Diagnosis

  • Learn About Your Diagnosis: Understanding the specifics of your diagnosis can help you make informed decisions.
  • Get Emotional Support: Talking to a counselor or joining a support group can improve your quality of life.
  • Take Care of Yourself: Eating a healthy diet and managing mental health through relaxation or physical activity can maintain your strength.
  • Seek Financial Assistance: Compensation for peritoneal mesothelioma is available through trust funds, lawsuits and workers’ compensation.

It’s important to remember you’re not alone. Many resources are available. Cancer treatment is constantly evolving, and survival has significantly improved for peritoneal mesothelioma thanks to advances in treatment.

What questions should I ask my doctor about peritoneal mesothelioma?

Asking your doctor questions about peritoneal mesothelioma can help in managing a diagnosis.

Peritoneal Mesothelioma Questions

  • Has my cancer spread out of my abdomen? How does that affect my prognosis?
  • What are my treatment options? What are the benefits? What are the risks or side effects?
  • How can I manage side effects and symptoms?
  • Do I qualify for surgery? Do I qualify for HIPEC?
  • Do I qualify for any emerging treatments or clinical trials? How can I access them?

Health care communication at these appointments often falls on caregivers. Be prepared ahead of medical appointments to ask questions and communicate clearly with doctors. This can help families feel informed and empowered.

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