Mesothelioma

The medical term for mesothelioma that develops in the abdomen is peritoneal mesothelioma, a variation of the disease that develops in the peritoneum, which is the layer of tissue lining the abdominal cavity wall. The predominant symptom is swelling of the abdomen, due to the production of abnormal amounts of the peritoneal fluid that is normally present in small amounts. The cancer cells develop in the peritoneum, creating small malignancies spread over the surface of the tissue.

The abnormal cells cause the development of excess fluid, which acts as a conduit for malignant cells into adjacent tissues including the lymph systems and eventually nearby organs in the abdominal cavity. Because symptomatic behavior occurs after the disease has matured to a degree the treatment options most patients face are for a cancer that has already moved through the early stages. Peritoneal mesothelioma is generally a diffuse form of cancer made up of a layer of small tumors; on infrequent occasions it will manifest as a single growth of greater mass.

Physical manifestations that begin to develop as the disease develops are similar to more common abdominal afflictions, which is why diagnosing abdominal mesothelioma can be a process of elimination. Annual diagnoses of the disease in the United States are no more than 500 occurrences per year. Those developing symptoms include:

There are instances of "dry" peritoneal mesothelioma where the development of excess fluid is not present. In those instances a single tumor may develop which can be seen in a CT scan. The diffuse small tumors normally associated with the disease can also be seen on a CT scan but require further diagnostic steps to determine whether they are in fact tumors or simply cystic growths. A sample of the abdominal fluid can be withdrawn using a procedure called paracentesis for diagnostic purposes, but even then the evidence of cancerous cells is not sufficient. A biopsy is required, most often performed through the naval with the assistance of a laparoscope.

If cancerous tissue is located the options for treatment depend on the stage to which the disease has advanced. If it has metastasized to organs within the body then palliative care is likely the only option. If the malignancy is sufficiently contained to be "debulked," the malignant peritoneal tissue may be removed along with growths that have developed in lymph nodes and adjacent surfaces such as the small bowel. Surgical resection is the preferred choice for patients who are healthy enough to recover from major surgical intervention.

The most successful post-surgical treatment has proven to be intraperitoneal chemotherapy that applies chemotherapy medications directly to afflicted areas within the abdominal cavity. The most common medication for this purpose is cisplatin, which is often heated before application. The most responsive cellular form of mesothelioma to this type of treatment is epithelioid; biphasic and sarcomatoid cells are not effectively reduced either by this type of chemotherapy or generalized chemotherapy.