As one of the several types of mesothelioma, peritoneal mesothelioma is a malignant tumor that develops in the lining of the abdominal cavity (known as the peritoneum). Peritoneal mesothelioma accounts for about 15% to 20% of all mesothelioma cases diagnosed throughout the world, making it the second-most common form of this variety of cancer. It is almost always fatal.
Due to its location in the body, peritoneal mesothelioma is sometimes referred to as abdominal mesothelioma.
Causes of Peritoneal Mesothelioma
As with any form of mesothelioma, exposure to asbestos has been shown to be the cause of nearly all peritoneal mesothelioma cases. A very small number of people with a specific genetic predisposition may also develop peritoneal mesothelioma after prolonged exposure to erionite, a naturally occurring mineral similar to asbestos.
While most asbestos fibers tend to lodge in the lining of the lungs, researchers have a few theories about why some individuals develop peritoneal rather than pleural mesothelioma.
- Some experts believe the asbestos fibers may be inhaled and transported through the lymphatic system to the peritoneal cavity.
- Others hypothesize that after the fibers are ingested and make their way to the intestinal tract, they may work themselves into the peritoneal cavity and peritoneum.
- Some researchers surmise that that the fibers captured and held by the mucus in the trachea or bronchi may eventually be swallowed.
Regardless of how the fibers reach the peritoneum, their presence in the abdominal area causes inflammation and, ultimately, tumors. As the malignancy grows, it covers the abdominal cavity and eventually may spread (metastasize) to other areas of the body.
Symptoms of Peritoneal Mesothelioma
Like all forms of asbestos-caused cancer, peritoneal mesothelioma can lay dormant in the system for up to fifty years. Victims are usually difficult to diagnose, because when the symptoms finally surface, it is often difficult to make connect them to asbestos, especially when the individual has not been exposed to the substance for many years.
Furthermore, the symptoms of peritoneal mesothelioma can be easily confused with those of other more common diseases. Therefore, many victims go undiagnosed or are improperly diagnosed for months before the proper conclusion is determined.
Symptoms of peritoneal mesothelioma include:
- Abdominal pain (acute to severe)
- Swelling of the abdominal region due to fluid accumulation
- Breathing difficulties
- Loss of appetite and/or weight loss
- Bowel obstruction
Symptoms may vary with each patient and may depend on a number of factors, including:
- Tumor location and size
- Patient’s age
- General health of the individual
When presenting symptoms for diagnosis, it’s important for patients to tell the doctor about their exposure to asbestos, even if the exposure occurred many years ago. This knowledge will aid in diagnosis and possibly spare the patient a number of unnecessary tests.
Diagnosis of this rarer form of mesothelioma is much the same as with pleural mesothelioma. Your doctor may order such tests as a traditional x-ray or perhaps a more sophisticated test, such as an MRI or CT scan.
While imaging technologies can provide some indication of peritoneal mesothelioma, doctors will usually order a tissue biopsy to make a conclusive diagnosis. The biopsy is performed using a peritoneoscopy or laparotomy to take a sample of the tissue around the abdominal cavity, which is then analyzed under a microscope to determine whether tumors are present. The biopsy can be uncomfortable, but it is usually over in just a few minutes.
Once a diagnosis is determined, an oncologist will help determine a course of treatment for the patient.
Because peritoneal mesothelioma is often diagnosed in its very late stages, tumor removal by surgery is usually not an option. However, if surgery is established as a viable option, it may involve excising a portion of the lining and tissue from the abdominal area to remove the tumor. If the tumor is unusually large, a lung or a section of the diaphragm may need to be removed as well.
Radiation may be aimed directly at the tumors or used as a palliative measure to relieve pain or lessen symptoms. However, radiation therapy will not cure mesothelioma. It is often used alongside chemotherapy treatment.
Common chemotherapy techniques for this kind of mesothelioma include intra-peritoneal chemo, which involves injecting chemotherapy drugs directly into the abdomen. Different drugs in various combinations are recommended, depending on each individual case. Like radiation, chemotherapy can be a palliative measure, relieving uncomfortable symptoms and improving the quality of life for mesothelioma patients.
Clinical trials are offered by researchers through many cancer clinics and health centers for those diagnosed with mesothelioma. These trials usually offer the opportunity to try experimental medications or emerging treatments that have not yet been shown to be completely effective and have not received approval from the FDA and other governmental organizations that oversee health care.
Although riskier than traditional treatments, new treatments may offer hope to those whose cancer does not go into remission using standard therapy techniques.
Because it takes so long to diagnose peritoneal mesothelioma, the outcome is not positive. As with other forms of the disease, most victims live for less than a year after diagnosis. The longest-known survivor of mesothelioma lived 19 years after diagnosis, but such cases are extremely rare.
Mesothelioma patient prognosis depends on a variety of considerations:
- The individual’s gender and age
- The stage of the disease at diagnosis
- Mesothelioma cell type
- Exact location of tumors in the peritoneum
Doctors and research scientists continue to look for ways to treat and cure mesothelioma and its symptoms, as well as prolong the lives of those who are affected.