At a Glance: Pleural Mesothelioma

[Part One]

This article on pleural mesothelioma is the first in a two-part series; it profiles two types of a disease that affects thousands of people in the U.S., who were exposed to asbestos during the latter part of the last century.

Two types of mesothelioma commonly strike people who have experienced asbestos exposure: pleural mesothelioma and peritoneal mesothelioma. The former is the most frequently diagnosed and describes a rare form of cancer that attacks the pleura—a protective lining that covers the lungs. In people diagnosed with this particular cancer, between 70 and 80% have been exposed to asbestos.

Asbestos is a mineral made up of tiny fibers. It was once a popular choice for the manufacturing of many consumer products—from roofing shingles to children’s toys. Touted for its strength and its ability to resist heat and flames, asbestos was in widespread use until the latter part of the 20th century, when it was identified as a highly toxic carcinogen and ultimately banned by the EPA.

People who have been exposed to asbestos—especially on a frequent and continual basis—are at risk for developing asbestosis, malignant mesothelioma and other types of cancer. All are the result of damage caused to the internal organs after asbestos is inhaled or swallowed. Illness does not typically onset until 20 to 50 years post-exposure. Toxic contact occurs when materials made from asbestos are broken up, causing the fibers to be released into the air.

Symptoms. Mesothelioma can go undetected for some time. The first noticeable symptoms of pleural mesothelioma include coughing, wheezing, shortness of breath and chest pain. One of the difficulties in diagnosing mesothelioma is the commonality of its symptoms. It can be difficult to distinguish between the early symptoms of mesothelioma and those of minor conditions, like the common cold and flu.

Diagnosis. Conclusively diagnosing mesothelioma requires a biopsy of the affected tissue—in this case, the pleura. Screening methods used to try and eliminate a diagnosis of mesothelioma, before performing a biopsy, include chest x-rays, MRIs and CTs.

Stages. There are three staging systems for pleural mesothelioma, but the most familiar to the majority of cancer patients is the TNM system. According to its classifications: stage 1 affects only one layer of the pleura; stage 2 affects both layers; stage 3 also affects the nearby esophagus, lymph nodes or chest wall; and stage 4 affects also other parts of the body.

Treatment. What type of treatment is selected depends on a few different factors, such as the stage of the cancer and overall health of the patient. Surgery, chemotherapy and radiation are the most common traditional treatment choices. Alternative and experimental treatments may also be used. One highly promising option that is currently being studied in clinical trials is immunotherapy. Regardless of the type, the earlier treatment is begun, the more likely it is to be effective.

Prognosis. Even with treatment, there is no known cure for pleural mesothelioma. Life expectancy can vary, depending on how early treatment is begun and the age of the victim, among other specifics.