What Is Peritoneal Mesothelioma?
Peritoneal mesothelioma is a rare cancer affecting your peritoneum. Your peritoneum is the lining of the abdominal cavity. Similar to other types of mesothelioma, peritoneal mesothelioma is mainly related to asbestos exposure.
Peritoneal mesothelioma is the second-most common type of this rare cancer. Pleural mesothelioma develops in the lungs and is the most common.
The primary proven cause of malignant peritoneal mesothelioma is asbestos exposure. The incidence is equal among women and men.
I tell my peritoneal mesothelioma patients they certainly do have treatment options. With the good treatment that we use now, the median survival can increase years versus the survival rate without treatment.Dr. W. Charles ConwayPeritoneal mesothelioma surgical oncologist
What Causes Peritoneal Mesothelioma?
Peritoneal mesothelioma develops over a long period of time. Most people will not notice symptoms until 40 years after asbestos exposure.
When the thin asbestos fibers are ingested, they can travel through the bloodstream to the abdomen. The trapped asbestos fibers cause inflammation and irritation, damaging DNA. This process can lead to abnormal cell growth, causing tumors to form.
Inhaled or swallowed asbestos fibers can pass through the bloodstream, digestive system and lymphatic system and travel to the peritoneum. Years of inflammation and scar tissue formation cause genetic damage and excess abdominal fluid buildup. As tumors develop and grow on the peritoneum, they put pressure on vital organs and can spread to form new tumors.
Other types of mesothelioma include pericardial (heart lining) and testicular (testes). Omental mesothelioma is extremely rare and forms in the omentum, the lining covering the stomach and other organs.
Symptoms of Peritoneal Mesothelioma
Peritoneal mesothelioma symptoms can include stomach pain, swelling, fever and unexplained weight loss. Often, patients don’t notice these symptoms until the cancer has progressed, so diagnosing it early is important.
- Abdominal pain and swelling
- Ascites (or peritoneal effusion, fluid buildup in the abdomen)
- Bowel obstruction
- Changes in bowel habits
- Chest pain
- Difficulty breathing
- Fatigue and weakness
- Loss of appetite
- Nausea and vomiting
- Night sweats
- Unexplained weight loss
These symptoms are like many other abdominal disorders. An accurate diagnosis often requires a mesothelioma specialist and a biopsy sample. People may develop other symptoms if tumors spread to organs in the abdominal cavity, including the liver or intestines.
Rare Symptoms of Peritoneal Mesothelioma
Serious but less common symptoms may get overlooked because of their rarity. Both common and less common symptoms of peritoneal mesothelioma may be mistaken for signs of other cancers or diseases.
- Abnormalities in liver function tests
- Blood clotting disorders
- Thrombocytosis (high platelet count)
- Hypoglycemia (low blood sugar)
- Pleural effusion (fluid buildup in the lung lining)
- Pericardial effusion (fluid buildup in the sac surrounding the heart)
- Neurological symptoms (such as seizures or paralysis)
A general medical oncologist has the training and tools to diagnose peritoneal mesothelioma. While any oncologist can diagnose the disease, a peritoneal mesothelioma specialist has the experience to treat it effectively. Seek a second opinion and treatment from a specialist to get the best care.
How Is Peritoneal Mesothelioma Diagnosed?
Peritoneal mesothelioma is diagnosed with a core needle or laparoscopic biopsy. A biopsy is the only way to confirm the presence of malignant mesothelioma cells. Imaging scans and blood tests play a role in diagnosing the type and stage of this rare cancer. The following tests help determine the spread of cancer and staging.
- Biopsies show what kind of cancerous cells are present.
- Blood tests reveal certain biomarkers associated with cancer.
- Imaging scans, such as X-rays, CTs, PETs or MRIs, show the size and location of tumors.
- Physical exams look for protruding tumors and a review of medical history assesses overall health and asbestos exposure.
Biopsies are samples of tumor tissue that pathologists examine under a microscope in a lab. Pathologists perform tests on the biopsy sample to reveal the kinds of cancerous cells, including epithelioid, sarcomatoid and biphasic types, within the tumors. They then summarize the results in a pathology report. Patients and their loved ones may request a copy.
When Should I See a Doctor?
Many doctors lack experience with the disease and may misdiagnose it as more common illnesses. Peritoneal mesothelioma misdiagnosis can delay proper treatment. The best way to get a diagnosis is to schedule an appointment with a mesothelioma specialist. Peritoneal specialists have the knowledge and tools needed to make a precise diagnosis.
The process for getting an accurate diagnosis may seem overwhelming because of the number of tests and unfamiliar terms and procedures. A mesothelioma specialist understands this and will work with you and your loved ones to make the diagnostic process a better experience.
The Life-Saving Impact of an Early Peritoneal Mesothelioma Diagnosis
Early detection of mesothelioma has a big impact on treatment outcomes and an increased chance of long-term survival. Because peritoneal symptoms can resemble those of more common conditions, it can lead to delays in diagnosis and treatment.
People who have a history of asbestos exposure and show signs of the disease should seek an experienced peritoneal mesothelioma specialist. Currently, there are no U.S. Food and Drug Administration-approved screenings for peritoneal mesothelioma. However, researchers are developing screening methods for earlier detection.
Staging Peritoneal Mesothelioma
The stages of mesothelioma describe the size of tumors and how far they have spread. The stage affects treatment options and helps assess a patient’s prognosis.
There is no official staging system for peritoneal mesothelioma. However, doctors have used the Tumor Node Metastasis system, or TNM, to define three peritoneal mesothelioma stages. Doctors also use the Peritoneal Cancer Index to define tumor stages within the TNM system.
- Stage 1: Cancerous tissue is minimal, tumors are only within the abdominal lining and lymph nodes are free of cancer.
- Stage 2: Cancerous tissue is moderate and tumors have not spread outside the lining or into lymph nodes.
- Stage 3: Cancerous tissue is more extensive and tumors may have spread outside the peritoneal lining or into lymph nodes.
More data is needed to clearly define the fourth stage. Many doctors consider stage 4 to involve extensive tumors that have spread to distant sites throughout the body. Most peritoneal patients are diagnosed at a later stage.
The Peritoneal Cancer Index is a tool doctors use to assess tumor location and spread in the abdomen. It helps them determine the approximate mesothelioma stage and appropriate treatments. Lower index scores mean the patient may qualify for surgery. Index scores above 20 indicate cancer has spread too far and the patient likely won’t respond well to surgery.
Peritoneal Mesothelioma Survival Rate and Prognosis
Survival with peritoneal mesothelioma varies depending on the treatment a person qualifies for.
- The 5-year survival rate for all cases of peritoneal mesothelioma is 65%.
- People who don’t qualify for surgery live about 13 months with chemotherapy alone.
- Over 50% of peritoneal patients who undergo surgery with HIPEC live more than five years.
- Surgery with HIPEC, post-operative chemotherapy and long-term chemotherapy has led to a 75% 5-year survival rate.
- The median survival for people who opt against treatment is six months.
Prognosis for peritoneal mesothelioma is generally poor for patients who don’t qualify for surgery, which can improve a patient’s prognosis significantly. The median survival of peritoneal mesothelioma patients who do not undergo any treatment is six months.
Mesothelioma statistics represent all patients and cannot predict an individual patient’s prognosis. Individual factors affect the patient’s cancer and health, including cancer stage, cell type, tumor grade, gender and treatments selected. Patients with epithelial cells have a longer life expectancy than those with other cell types. Epithelial cells tend to respond better to treatments such as chemotherapy.
Is There a Cure for Peritoneal Mesothelioma?
Unfortunately, there is currently no cure for peritoneal mesothelioma or any other type of mesothelioma. But there is hope among the medical community as treatment and survival continue to improve through clinical trials and research. Those eligible for surgery and hyperthermic intraperitoneal chemotherapy, or HIPEC, typically live longer than five years. Some patients may be eligible for repeat surgery with heated chemotherapy if a recurrence happens.
In 2017, mesothelioma expert Dr. Paul Sugarbaker reported improved survival among patients who received early post-operative chemotherapy and long-term chemotherapy after cytoreductive surgery with heated chemotherapy. Surgery with HIPEC, post-operative chemotherapy and long-term chemotherapy worked best. About 75% of these patients lived longer than five years.
Treatment for Peritoneal Mesothelioma
Chemotherapy is the most-used treatment for peritoneal mesothelioma. The most effective treatment option is a multimodal therapy approach that incorporates surgery and hyperthermic intraperitoneal chemotherapy.
HIPEC involves a multidisciplinary team of surgical oncologists, medical oncologists and other experts to execute. Not all peritoneal mesothelioma patients qualify for this cytoreductive surgery.
The treatment options your doctor recommends for you will depend on your stage, tumor cell type and overall health. Other treatment options for peritoneal mesothelioma include immunotherapy and surgery.
Peritoneal Mesothelioma Chemotherapy
Patients who don’t qualify for surgery with HIPEC can receive systemic (whole-body) chemotherapy. Some patients receive only intraperitoneal chemotherapy. Chemotherapy combined with cisplatin and pemetrexed has the following benefits:
- A response rate of about 30%.
- Average progression-free survival of about 11.5 months.
- Median survival around 13 months.
- Chemotherapy delivered directly to the peritoneum without surgery has a higher response rate of 47%.
- When combined with heated chemotherapy given during surgery, the response rate is 84.6%
Chemotherapy drugs can shrink peritoneal mesothelioma tumors and slow the growth and spread of cancer.
Hyperthermic Intraperitoneal Chemotherapy (HIPEC) Surgery
Cytoreductive surgery is used during a peritonectomy. It attempts to remove as much cancer as possible. Heated chemotherapy is applied locally to the abdomen before the surgery ends. Doctors only perform this procedure on a case-by-case basis. A 2022 study in the Journal of Clinical Haematology reported that more than 80% of the patients who underwent HIPEC lived five years or longer.
The chemotherapy did what it was intended to do and it killed the cancer. Since the HIPEC procedure, I have not had any cancer recurrences. I’m a 15-year and counting survivor.Tamron LittlePeritoneal Mesothelioma Survivor
“Peritoneal mesothelioma patients I speak with commonly ask about the HIPEC procedure,” said Dr. Snehal Smart, a Patient Advocate at The Mesothelioma Center. “They ask about how doctors determine who will receive this treatment. They also ask if they’ll need further chemo after a HIPEC procedure.”
A qualifying patient for HIPEC surgery is younger and in good enough health to tolerate the intensive 12-hour procedure and recovery. Doctors evaluate a patient’s performance status, considering their overall health, to identify suitable candidates. Apart from cancer, patients must be healthy enough to undergo the aggressive treatment.
Peritoneal Mesothelioma Immunotherapy and Emerging Treatments
There is no consensus on the role of immunotherapy in the treatment of peritoneal mesothelioma, according to a 2023 review in Molecular and Clinical Oncology.
“Patients have a lot of questions about participation in immunotherapy-focused clinical trials as a treatment option,” said Patient Advocate Danielle DiPietro.
Immunotherapy has been approved by the U.S. Food and Drug Administration for pleural mesothelioma, but not for the peritoneal type. People with peritoneal mesothelioma are historically excluded from immunotherapy clinical trials because of the rarity of the disease.
Results from the few immunotherapy trials that included peritoneal patients have been mixed. A few immunotherapy studies have shown a benefit for peritoneal patients, while other studies showed no benefit.
Clinical trials test innovative therapies to discover new treatments for mesothelioma. Emerging treatments under investigation for peritoneal mesothelioma have included immunotherapies and targeted therapies.
Palliative Care for Peritoneal Mesothelioma
Many peritoneal patients receive palliative care, which controls symptoms and can improve quality of life. For example, a paracentesis procedure drains excess fluid from the abdomen to lessen pain.
A palliative care specialist prescribes medications to control pain and side effects. They may refer patients to physical or occupational therapy or recommend complementary therapies.
Managing a Peritoneal Mesothelioma Diagnosis and Coping Tips
Managing a cancer diagnosis is a difficult and emotional experience for patients and their loved ones. It’s a journey of multiple tests and uncertain results. There is no one right way to cope with cancer. Every individual experience is different.
- 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 quality of life.
- Take Care of Yourself: Eating a healthy diet and managing mental health through relaxation or physical activity can maintain strength.
- Seek Financial Assistance: Compensation for peritoneal mesothelioma is available through trust funds, lawsuits and workers’ compensation.
It’s important for cancer patients to remember they’re not alone. Many resources are available to help them cope with the diagnosis. Cancer treatment is constantly evolving, and survival has significantly improved for peritoneal mesothelioma thanks to treatment advancements.
Finding Peritoneal Mesothelioma Specialists and Cancer Centers
Top Peritoneal Mesothelioma Doctors
Top Treatment & Cancer Centers for Peritoneal Mesothelioma
Questions to Ask Your Doctor About Peritoneal Mesothelioma
While a general oncologist is qualified to answer these questions, a peritoneal mesothelioma specialist has the expertise to review your case and provide answers based on your unique needs. Consider asking the following questions when you meet with your doctor.
- 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.
Common Questions About Peritoneal Mesothelioma
- How does peritoneal mesothelioma develop?
Asbestos fibers that were inhaled or ingested cause inflammation and DNA damage over an average latency period of 40 years before causing cells in the abdominal lining to turn cancerous.
- How common is peritoneal mesothelioma?
Of the estimated 3,000 mesothelioma cases diagnosed in the U.S. annually, peritoneal cases account for 300 to 500 cases. Incidence data shows about one to two cases occur per million people each year.
- Is peritoneal mesothelioma considered terminal cancer?
Malignant peritoneal mesothelioma is considered terminal at all four stages. Clinical trials search for a cure. They test new treatments, including immunotherapy and multimodal therapy.
- Can peritoneal mesothelioma go into remission?
Yes, about 12% of peritoneal mesothelioma patients who undergo aggressive treatment experience complete remission, according to a 2020 study published in Surgical Oncology & Clinical Practice Journal. Partial remission is also possible. Remission is not the same as a cure. Doctors monitor patients because cancer can return after entering partial or complete remission.