Stages of Diagnosis
The basis of staging of mesothelioma is from the recommendation of the International Mesothelioma Interest Group. It is the process of determining the degree of how the cancer has spread that involves the use of imaging test such as X-rays, CT scan and MRI scans. The type of treatment most effective and life expectancy for mesothelioma patients depends largely on the extent of spread known stage of the cancer. The staging classification, however, exists for pleural mesothelioma since it is the most common and frequent for studies to be conducted on. These are the Butchart system, the TNM system and the Brigham system. Little difference exists among the three systems.
Butchart System
The often used form of mesothelioma cancer staging is the Butchart system, which was developed by mesothelioma expert Dr. Eric Butchart. Dividing mesothelioma stages in to four, it is based mainly on the progression of primary tumor mass, ignoring secondary tumors and medical complications as result of cancer presence in the body.
Stage I – This is the given designation when the primary mass or tumor is present in either the right or left pleura and may at times be at lung, pericardium or diaphragm on the same side. Growth of the mass has been notably restricted to only one side of the body.
Stage II – Mesothelioma is said to be in this stage when the mass has extended to the chest wall. In many cases of Stage II mesothelioma, the presence of the primary mass will have grown to the esophagus, heart, or the lymph nodes situated in the chest.
Stage III – This designation means that the primary mass has penetrated the limits of the diaphragm and has breached the peritoneum, or abdominal cavity. At this point in cancer development, primary mass may have spread to the lymph nodes beyond the chest.
Stage IV – At this point, the cancer has spread through the bloodstream to other parts of the body such as the liver, brain and bone. This stage is known as “distant metastases.”
TNM System
Another cancer staging system was developed by the International Mesothelioma Interest Group known as the TNM system. The TNM system describes the extent of the primary tumor (T), the absence or presence of cancer in nearby lymph nodes (N), and the absence or presence of distant metastases (M). Once the information about the three factors above are combined in a process called stage grouping, the earliest determined stage being stage 1 and the advanced is stage 4.
Stage I -The masses are rigidly localized, affecting one layer of the pleura, or lungs. At this stage in development, the cancer may also have grown into the covering of the heart and the diaphragm.
Stage 2 – Mesothelioma has spread from the pleura on one side to the nearby lymph nodes next to the same side of the lung. It may also have spread into the same side of the body.
Stage 3 - Mesothelioma has spread into the chest wall, lymph nodes, heart, esophagus, or other organs in the chest on the same side
Stage 4-This stage is where any mesothelioma with evidence of distant metastases (spread to other organs through the bloodstream) or spread to organs beyond the chest or abdomen.
Brigham System
While the other cancer staging systems is based on how far the cancer cells had spread or tumor has grown, this system measures the stage if reductive surgery is an option or not. This system uses a four distinctive staging as well, which considers two factors: the capacity of the mass to be successfully removed or not and presence or absence of cancer cells in the lymph nodes. Because rarely can the mesothelioma be surgically cured, this type of staging is not often used.
Stage 1 – Mesothelioma can be removed with surgery and there are no cancer cells in the lymph nodes.
Stage 2 – Mesothelioma can be removed with surgery but cancer cells have already spread to the nearby lymph nodes.
Stage 3 – The masses cannot be removed with surgery because it has spread into the chest wall, heart, or through the diaphragm into the peritoneum. There may or may not be cancer cells present in the lymph nodes.
Stage 4 – The cancer has greatly metastasized, where cancer cells had spread via the bloodstream to other organs in the body possibly the liver, brain or even to the bones.
Screening
There is no standard protocol for screening people who have been exposed to asbestos. Mesothelioma is even more so difficult to treat partly because it is usually not detected until the disease has progressed to the late stages. Mesothelioma patients would see an improved prognosis if the disease could be detected earlier. Screening tests may be sufficient to diagnose mesothelioma earlier than conventional methods resulting to improved survival outlook for patients and may aid management of aggressive cancer.
The serum osteopontin level might be useful in screening people for mesothelioma. The level of osteopontin is high in numerous inflammatory and fibrotic lung diseases, suggesting that it may be useful for screening. Doctors have begun testing using the Mesomark assay that measure for levels of soluble mesothelin-related proteins (SMRPs) secreted by mesothelium cancer cells. Some researchers see this as a breakthrough in mesothelioma detection as certain elevated levels of SMRP indicate the presence of mesothelioma. The test work best when through early detection of the biomarker in a diseased blood lead to an early diagnosis providing more treatment options and a better prognosis for the patient.
Mesomark blood test is also helpful for monitoring the progress of treatments in patients who have already been diagnosed with mesothelioma. In February 2007, the results of a study released by researchers at New York University show that the test may be effective. Dr. Harvey Pass of the Department of Cardiothoracic Surgery at NYU’s School of Medicine commented on a press release that their findings not only show that SMRP is indeed a valid biomarker for mesothelioma, but also justify further research as a prospective screening test. Dr. Pass pointed out that the test might assist researchers on the way towards improving survival rates and the quality of life for patients diagnosed with this aggressive and often fatal disease.
Mesomarktest was developed by Fujirebio Diagnostics Inc. of Malvern, Pennsylvania and was first released in Australia in March 2005 and eventually in Europe of the same year. Only in January 2007 that the U.S. Food and Drug Administration approved the blood test for humanitarian use.