Mesothelioma is a rare and deadly form of cancer infecting the lining of the lungs and chest cavity. It is caused by exposure to asbestos, and due to its long latency period, it is often not diagnosed until late in its progression. The stage of the disease can determine a patient’s prognosis and inform their treatment options, so it is important for patients and their doctors to keep a close eye on the patient’s stage. Understanding the stages of mesothelioma can help patients communicate with their doctor and make sure their treatment plan works for them.
Like other forms of cancer, mesothelioma’s progression is measured in four stages; as a patient’s condition worsens, they are categorized into the next stage. The stages are primarily determined by the size of the tumors and their location in the body, as well as tumor grading and differentiation. Changes to these factors show whether the disease has worsened and spread or metastasized to other areas. While tumor size and location can impact the symptoms that a patient experiences, the symptoms themselves are usually not considered when determining a patient’s stage.
One of the difficulties with diagnosing mesothelioma is the lack of symptoms in the early stages. Early-stage mesothelioma presents relatively small tumors and does not have a noticeable impact on the body, so patients may not realize something is wrong until the tumors grow to a much larger size. Early diagnosis is key to successfully treating malignant mesothelioma, but it is not always possible.
A patient in stage one of malignant pleural mesothelioma will have small tumors that are confined to the pleura, or the lining of the lungs. Mesothelial cancer cells will not be found in other parts of the body, and the tumors will not be large enough to affect the patient’s breathing or cause any pain in the chest. At this stage, most conventional cancer treatments are available to patients, including surgery, chemotherapy, and radiation, and most treatment plans will begin with surgery to remove the tumors. With surgery, patients have an average life expectancy of close to two years, and some may experience long-term survival.
Patients are moved to stage two when tumors begin to grow beyond the mesothelial lining and infect the nearby lymph nodes, diaphragm, esophagus, or lung tissue within the lining. Tumors are still small, and most patients in this stage continue to show no symptoms, though some may experience difficulty breathing when exercising or a slight cough. Stage two malignant pleural mesothelioma patients are usually still eligible for surgery to remove the tumors and may be treated with chemotherapy and radiation as well. Patients at this stage can live up to three to five years with an average life expectancy of 20 months.
The third stage of pleural mesothelioma typically includes respiratory symptoms, such as chest pain, difficulty breathing, wheezing, and cough, as well as fever and unusual weight loss. Tumors in the pleura will be larger, and the cancer will be found in other tissues and organs in the chest area, making some patients ineligible for surgery. Patients in stage three are often treated with chemotherapy and may be eligible for unique treatments, such as clinical trials or immunotherapy; in some cases, doctors may choose to provide palliative care instead to help patients manage their pain and preserve their quality of life. Patients who qualify for surgery have a much better life expectancy, living an average of about 18 months; age and overall health play a big role in determining what treatment options for mesothelioma are available.
Mesothelioma is more likely to metastasize locally in and around the area where it is first presented rather than travel to distant parts of the body. This type of distant metastasis is only seen in stage four malignant mesothelioma patients, who may have tumors present in the brain, bones, or other tissues not located in the chest cavity. Patients in stage four will experience severe respiratory symptoms, including difficulty breathing, acute chest pain, coughing up blood, and difficulty swallowing. They may also experience fever, weakness or fatigue, night sweats, nerve sensitivity, weight loss, and loss of appetite. Stage four patients may also be eligible for clinical trials and immunotherapy, but most receive chemotherapy and palliative care to control their symptoms. The average life expectancy at this stage is about 15 months.
There are three staging systems used to track the progression of malignant pleural mesothelioma. The most commonly used is the Tumor, Node, and Metastasis (TNM) staging system, developed by the American Joint Committee on Cancer (AJCC). This system assigns a stage by measuring three metastasis factors: the growth of the primary tumor (T), the spread of cancerous cells to nearby lymph nodes (N), and the infection of other organs (M). Doctors using this system can indicate both the clinical stage as indicated by imaging tests, such as CT or PET scans, along with physical examination, as well as the pathological stage, which is determined by surgical findings.
Mesothelioma tumors can also be staged using the Brigham system, which focuses on the operability of a tumor. Oncologists may also refer to the Butchart system, which follows a similar trajectory to the TNM system but mainly focuses on the location of the primary tumor as its benchmark.
Pleural mesothelioma, which infects tissues in the chest cavity, is the most common form of mesothelioma, accounting for approximately 75 percent of cases. Patients suffering from peritoneal mesothelioma, which infects the lining of the abdomen, may have different symptoms than those with pleural mesothelioma. Peritoneal mesothelioma patients often experience symptoms more closely related to the digestive tract; in early stages, this could present as weight loss or bloating, then progress to abdominal pain, constipation, diarrhea, abdominal swelling, or bowel obstruction in later stages.
There are some similarities, however. Symptoms for peritoneal mesothelioma patients will typically follow the same pattern as pleural mesothelioma patients, with few showing symptoms in stages one and two and symptoms progressing through stage three and presenting as severe in stage four. Peritoneal mesothelioma patients may also experience fever, fatigue, and pain as the disease worsens.
Peritoneal mesothelioma may also be rated on a different staging system than pleural mesothelioma. Malignant peritoneal mesothelioma does not have its own dedicated staging system yet, and while some use the TNM system for pleural mesothelioma to stage the disease, others use the Peritoneal Cancer Index, which is used to stage other abdominal cancers. Some oncologists will limit their categorization to either localized or advanced.
Mesothelioma can also infect the pericardium or the testes. While there is a TNM system for peritoneal mesothelioma in process, there is still not enough data from these two forms of the disease to build accurate staging systems. Pericardial mesothelioma and testicular cancer are both extremely rare; there are approximately 50 cases of pericardial mesothelioma in the United States each year, and only 100 cases of testicular mesothelioma have been recorded.
If you or a loved one has been diagnosed with mesothelioma, call one of our respected Philadelphia mesothelioma lawyers at Brookman, Rosenberg, Brown & Sandler. Our experienced legal team will thoroughly review the facts of your case to determine who is at fault for your asbestos exposure and hold them accountable. Contact us online or call us at 215-569-4000 for a free consultation today. Located in Philadelphia, we serve clients throughout New Jersey and Pennsylvania, including Delaware County, Chester County, and Philadelphia County.