Peritoneal mesothelioma is a type of cancer caused by exposure to asbestos. It happens when the asbestos fibers irritate the lining of the abdominal wall and inner organs of the abdomen. This causes cellular mutation and the formation of tumors. The most successful treatment for this disease is surgery with heated chemotherapy. With this treatment, many patients live years beyond their diagnosis.
Understanding Peritoneal Mesothelioma
Peritoneal mesothelioma is very rare. It accounts for only about 10-20 percent of all incidents of mesothelioma. The cancer develops in the lining of the abdomen, called the peritoneum. It may be caused by ingesting asbestos fibers. After swallowing the fibers, the asbestos may travel to other parts of the abdomen to cause cancer.
Veterans often develop the disease because of exposure to asbestos in their military career. Many veterans also moved on to work in industrial and construction trades. These are careers where asbestos exposure was the most common.
What is the peritoneum?
The peritoneum is a protective membrane found around the abdominal organs. It has two layers. The visceral layer surrounds the organs. The parietal layer lines the abdominal cavity. Mesothelioma can occur in either layer of the peritoneum.
Why does peritoneal mesothelioma occur?
No one knows exactly how the asbestos fibers get to the peritoneum. Experts believe that the fibers get to the abdomen by swallowing asbestos fibers or by inhaling the fibers. Then the fibers travel to the abdomen through the lymph system. The lymphatic system is part of the immune system that collects and stores foreign invaders, such as bacteria, viruses and foreign particles.
Peritoneal mesothelioma patients have the best prognosis compared to patients with other types of mesothelioma. Results from a study published in April 2017 showed that two patients are “alive and well 10-13 years from diagnosis.” The two patients got standard treatment, relapsed and then had novel treatments that prolonged their lives.
Symptoms of Peritoneal Mesothelioma
The symptoms of peritoneal mesothelioma depend on where the cancer has begun. Most of the early symptoms of peritoneal mesothelioma may not seem dangerous.
In the early stages, there might only be:
- Abdominal pain
- Swelling from extra fluid in the abdomen
Often there are no symptoms or only nonspecific symptoms until the cancer has advanced. In such cases, there may be unexplained weight loss and fatigue. When mesothelioma has spread, it is harder to cure.
Later signs of peritoneal cancer include:
- Night sweats
- Fullness in the abdomen
- Nausea and/or vomiting
- Weight loss
- Anemia (low blood count)
It takes up to 50-60 years between the time of exposure to asbestos and the development of peritoneal mesothelioma. The asbestos fibers remain in the lining of the abdomen for many years before the irritation leads to tumor development.
Diagnosis of Peritoneal Mesothelioma
The nonspecific symptoms of peritoneal mesothelioma can make it hard to diagnose. Doctors may begin to suspect this disease if you have both abdominal symptoms and a history of exposure to asbestos. If you were in the military from World War II and onward, there is a good chance that you were exposed to asbestos in your service. Chances that you were exposed are higher if you worked in construction or in naval shipyards.
An X-ray or CT scan of the abdomen or chest may show areas where tumors might be present. The images look like thickened areas of the lining around the organs or the abdominal cavity. Extra fluid might also show up on the CT scan of the abdomen. This is a natural reaction to having irritation in the peritoneal lining.
If doctors find an area of thickening, the next step is taking a biopsy. In a biopsy, doctors take a sample of tissue from the peritoneum where it has thickened or where nodules (lumps) have formed. Only a biopsy showing mesothelioma cells can diagnose mesothelioma with certainty.
Obtaining a Biopsy
There are different ways to get a tissue sample. A doctor can insert a thin needle into the fluid of the abdomen. Then the doctor draws the fluid out through the needle. Thousands of cells from inside the fluid can be drawn out and looked at under the microscope. Cancerous cells may be found in the peritoneal fluid. This can accurately diagnose peritoneal mesothelioma up to 84 percent of the time.
Other methods of getting biopsies of cancerous areas are called endoscopic biopsies. This method involves a camera and small tools inside the abdominal spaces to look for and sample for cancer.
Laparoscopy involves a camera inserted into the abdomen. Cancerous cells can be found in a tissue sample.
A biopsy can also be taken by doing open surgery on the abdomen and looking for possible cancerous areas.
Treatment of Peritoneal Mesothelioma
Surgery is the most effective treatment for peritoneal mesothelioma. Whether you’re eligible for surgery depends on your overall health and stage of disease. Patients with more advanced mesothelioma may need treatments to shrink and contain tumors before surgery is feasible. Surgery can be done along with chemotherapy and radiation to try and reduce the number of cancer cells in the body.
Cytoreduction with HIPEC is the most successful treatment for peritoneal mesothelioma. HIPEC stands for “hyperthermic intraperitoneal chemotherapy.” Dr. Paul Sugarbaker, the leading peritoneal mesothelioma specialist in the country, developed the procedure. In his treatment, all visible signs of cancer are removed from the abdomen with surgery. Then heated chemotherapy agents are put inside the abdomen to kill any remaining cancer cells. Some people who have had this procedure have lived more than five years after treatment.
Patients in earlier stages of their disease live longer and have more treatment choices than people with a more advanced diagnosis. Your prognosis depends on how far the disease has spread, your health, the cell type found in the mesothelioma and the treatments you are eligible for. About 25 percent of all peritoneal mesothelioma patients will live for three years with the best treatment possible.
Because treatment is so important to the length of survival, it is important to find a mesothelioma specialist. These doctors have invaluable experience treating this rare disease that general oncologists don’t have.
Surgery for Peritoneal Mesothelioma
Surgery is the best way to remove visible signs of cancer. It is very effective for early-stage patients. If the surgery is designed to be curative, all areas affected by cancer are removed. If the surgery is designed to be palliative, only those parts of the cancer that are causing the most symptoms are removed. Palliative surgery can relieve pain and other symptoms of advanced mesothelioma.
“For patients referred very early, I would say we are successful nearly 100% of the time,” said Dr. Paul Sugarbaker in 2011. “We can get a complete cytoreduction with the primary cancer resection, removing the peritoneal metastases, and using HIPEC. We can almost promise those patients that they will not have further peritoneal metastases.”
Common surgeries done for peritoneal mesothelioma include:
- Cytoreductive surgery. This aims to remove as many cancerous cells as possible throughout the abdomen.
- Peritonectomy. This tries to remove the cancerous cells and the lining around cancerous cells.
- Bowel resection. This removes parts of the intestines that have advanced cancer on them.
- Organ removal. This can involve removal of the spleen, kidneys, stomach or liver affected by cancer.
Chemotherapy and Radiation for Peritoneal Mesothelioma
Chemotherapy can kill cancer cells that cannot be seen by the naked eye. Doctors may prescribe chemotherapy before surgery, during surgery or after surgery for cancer. Common chemotherapy drugs for peritoneal mesothelioma include cisplatin, carboplatin, pemetrexed and gemcitabine.
HIPEC is a type of chemotherapy that uses heated chemicals during surgery. Heating the chemotherapy drugs and applying them directly to the abdomen can be far more effective than traditional chemotherapy.
While radiation can shrink areas of cancer and can kill cancer cells, it is risky to do this in the entire abdomen. Radiation cannot tell the difference between cancer cells and healthy cells. So it may do more harm than good to the abdominal organs. Your specialist will determine if radiation makes sense for you
You can be a part of experimental therapies for mesothelioma, especially if you get treatment at one of the top mesothelioma centers in the country. In a clinical trial, doctors test new techniques to see if it can help control the disease better than existing treatments. Some mesothelioma survivors have clinical trials to thank for their longer lives. Clinical trials are also good to consider if you aren’t responding well to your current treatments.
Becoming a Survivor
Veterans diagnosed with peritoneal mesothelioma have cause for hope that some mesothelioma patients don’t have. Science is progressing to the point where peritoneal patients are able to live with the disease for a long time. Most of these patients also have independent lives worth living.
Things to consider about your diagnosis:
- Peritoneal patients have the best life expectancies.
- Seeing a specialist is most important factor in prolonging your life.
- Discuss all available treatment options with your doctor.
Twenty years ago it was unthinkable that there would be mesothelioma survivors. Yet, thanks to emerging treatments like cytoreduction with HIPEC, that has become a reality. You can learn more about your treatment and support options in our free Mesothelioma Veterans Guide.