How Is Mesothelioma Diagnosed & Staged?
by Contributing Writer
Mesothelioma is a cancer that affects cells that line the body cavities, such as the chest and abdomen. It is most commonly found around the lungs, often as a result of asbestos exposure. About 77 percent of people with this type of mesothelioma have been exposed to significant amounts of asbestos. There are 2,000 to 3,000 cases of mesothelioma diagnosed every year in the United States.
Mesothelioma patients often go to a doctor complaining of chest pain, and several investigative tests may need to be done before a definitive diagnosis is made. Radiological testing, such as X-rays, MRIs or CT scans may or may not show the nodules and plaques usually formed by mesothelioma, but will often show excess fluid around the lungs. This can be a symptom of many different diseases. This fluid may be partially drained and tested, though mestothelioma cells are often not contained in the fluid. However, the analysis can help rule out other causes for fluid accumulation. A biopsy is performed, with the aid of a tiny camera inserted into an incision in the chest, called a thoracoscope. The cells are then analyzed through staining tests, immunochemistry tests and microscopic examinations, to determine if the sample is positive for mesothelioma or another type of lung cancer. A biopsy will yield a definitive diagnosis 98 percent of the time.
Stage 1 indicates that the disease is confined to the parietal pleura, a membrane that lines the chest wall. There is no cancer in the lymph nodes at Stage 1.
In Stage 2, the cancer has spread to the lymph nodes next to the lung.
Stage 3 represents an extension of the disease into the chest wall, through the diaphragm, or to lymph nodes on the same side as the tumor, but farther away from the lung.
Stage 4 indicates that the cancer has spread to the opposite lung, or to organs in abdomen or neck.