Peritoneal mesothelioma is type of cancer that causes tumor formation in the lining of the abdomen or mesothelium. Mesothelioma is a rare, highly-aggressive and malignant cancer with only about 3,000 new cases emerging each year. Peritoneal mesothelioma is the second-most common type of the cancer, representing 10 to 25% of all new cases.
Peritoneal mesothelioma, like other types of this cancer, can take up to 20 to 50 years to develop after asbestos exposure. Because of this long “latency” period, symptoms may develop slowly and may be mistaken for other disorders. As it is a rare and highly aggressive cancer, it is vital that patients seek treatment from a mesothelioma specialist.
About Peritoneal Mesothelioma
The peritoneum is a membrane-like lining on the inside of the abdominal cavity. Peritoneal mesothelioma develops in a particular layer of this lining, known as the mesothelium. It is caused by ingestion of the thin, needle-like fibers of asbestos which lodge in the peritoneal lining. After a long period of time, the fibers can cause inflammation and genetic mutations, causing mesothelial cells to divide uncontrollably, resulting in tumor formation.
The great majority of peritoneal mesothelioma cases have been caused by asbestos exposure which prior to the 1970s was widely used as insulation in high-heat industries. Though the U.S. government began to implement a series of asbestos bans, it is still present in some products today and due to the long latency period, new peritoneal cases continue to emerge.
Most peritoneal mesothelioma diagnoses are made in people who had occupational exposure of asbestos due to work in industries such as auto manufacturers, steel workers, pipe-fitters, ship builders, and those who worked in demolition and construction. Family members of these workers may also have been exposed to asbestos dust which came into the home through contaminated clothing.
Besides peritoneal mesothelioma, the cancer may also develop in other areas of the body including the lungs, heart and testicles.
Peritoneal Mesothelioma Symptoms
Symptoms of peritoneal mesothelioma are caused by tumor growth and inflammation in the abdomen which may result in ascites or fluid collection in the abdomen. Symptoms of peritoneal mesothelioma may include:
- Abdominal swelling – caused by tumor growth and fluid collection in the abdominal cavity
- Abdominal pain – also due to tumor growth and fluid collection in the abdominal cavity
- Shortness of breath – caused by tissue swelling and fluid collection which may compress the lungs
- Bowel difficulties – from compression of the intestines from tumor formation or fluid collection
- Vomiting – due to compression of the stomach and intestines
- Fatigue – a general symptom of cancer and due to lack of food intake and difficulty breathing
- Weight loss – due to lack of food intake and also a general symptom of cancer
- Fever – from inflammation caused by cancer
Symptoms of peritoneal mesothelioma may develop slowly an d worsen over time as the cancer progresses.
Diagnosing Peritoneal Mesothelioma
Because the latency time for development of peritoneal mesothelioma is so long, it may be difficult it diagnose. Symptoms may mimic those of other disorders and because the cancer is so rare, the disease may be mistaken for another disorder.
When symptoms do not resolve over time and other disorders have been ruled-out, the doctor may perform imaging studies including:
- CT Scan
- PET Scan
When imaging studies result in a suspected case of peritoneal mesothelioma, certain blood tests to detect proteins released by cancer cells may be performed. Results of imaging studies and blood testing will commonly be confirmed by a biopsy procedure in which tumor tissue is removed and examined under a microscope. The biopsy will confirm the cancer diagnosis and identify the particular type of cancer cell the tumor contains.
Staging of Peritoneal Mesothelioma
Once the diagnosis of peritoneal mesothelioma has been made, the cancer will be categorized into one of the four stages. Stage 1 cancer is the least developed but is rarely diagnosed with Stage 4 being the most advanced category. Cancer staging will help to determine the type of treatment that may be most appropriate.
There are several staging systems for cancer but most commonly, the TNM system will be used. The TNM system bases stage categorization on tumor size (T), involvement of lymph nodes (N), and how far the cancer has spread or metastasized (M).
- Stage 1 – Tumor is still in the peritoneal layer and there are no cancer cells any lymph nodes. Peritoneal mesothelioma is rarely diagnosed at this stage
- Stage 2 –Tumor is larger but has not spread far beyond peritoneal area and some local lymph nodes do contain cancer cells.
- Stage 3 – Tumor(s) are significantly larger or more than one exists and it has penetrated into surrounding tissue such as the abdominal muscle layer. There is also cancer cell presence in more lymph nodes, including nodes that are further from the abdomen.
- Stage 4 – Cancer cells have traveled to other areas of the body and begun growing tumors of mesothelioma tissue on other organs such as the brain, kidneys, lungs or liver.
Treatment of Peritoneal Mesothelioma
Treatment options for peritoneal mesothelioma are identified by the stage of cancer and the type of cells that were identified during biopsy. In addition, patient specifics such as symptom severity, general health and other factors may affect treatment decisions.
Peritoneal mesothelioma that is diagnosed at earlier stages will have more options for treatment and the success of those treatments may be higher. At later stages, treatment options are often limited to palliative care to increase patient comfort. Options include:
- Surgery – removal of the tumor, along with a healthy margin of tissue may be successful in earlier stages. In many cases, surgery will be performed alongside other treatment methods. In the later stages, surgery to remove tumor and affected tissue is done to decrease severity of symptoms such as intestinal obstruction.
- Traditional chemotherapy – cancer-killing medications are given through intravenous infusion or as oral tablets or capsules. Chemotherapy is often used in combination with surgery to ensure that cancer cells are killed. It may also be used to shrink tumor size prior to surgery or to improve quality of life.
- Radiation – radiotherapy involves delivery of concentrated energy beams which are focused on the tumor to kill cancer cells. Radiation therapy may have limited use when the tumor is located closer to vital organs. It may be used alongside other treatments but it may also be used only to shrink tumor size in the same manner that chemotherapy is used prior to surgery or for symptom resolution.
- Newer treatments – newer medications and immunotherapy agents are constantly in development, some of which may be available through clinical trials. These treatments have not yet been approved for general use but may show promise for peritoneal mesothelioma treatment.
Peritoneal Mesothelioma Treatment Cost
Peritoneal mesothelioma has significant financial implications. The cost of treatment may be high and the patient or family may have also suffered due to loss of wages and loss of life. As a clear connection between asbestos exposure and peritoneal mesothelioma has been established, victims may be eligible for financial assistance or coverage.
Some victims or loved ones have received lawsuit settlements reaching into the hundreds of $millions from companies directly involved in the asbestos industry. Others may be eligible for financial assistance due to the establishment of a fund which still contains an estimated $30 billion. As each case of peritoneal mesothelioma is different, victims or loved ones of those diagnosed with the disease should seek legal advice from a mesothelioma expert.