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Staging is a medical term that describes the amount of a disease found in a person’s body. Staging is critical at the time of an initial diagnosis in addition to following any treatment invention. Any choices made about what type of treatment should be utilized are made based on a disease’s stage.
How Mesothelioma Is Staged
Staging for mesothelioma involves categorizing mesothelioma based on the extent of the disease in a person’s body. The staging process is applied to all types of cancer, even though certain staging systems are often created based on the unique elements of certain types of cancer. Mesothelioma staging is made during a person’s first diagnosis. Medical professionals who treat people with mesothelioma routinely rely on the general characteristics of cancer to stage the illness.
The Four Stages of Mesothelioma
Medical professionals categorize malignant mesothelioma into four stages. While stage 1 mesothelioma is viewed as early-stage mesothelioma, stage 4 is the most advanced stage for mesothelioma. In most situations, people are diagnosed with mesothelioma after stage 1. Consider the following details about the various stages of mesothelioma
- Stage 1. In this stage, a person’s tumor is only in the mesothelial lining and has not spread.
- Stage 2. In this stage, cancer spreads to nearby organs including the diaphragm or lung.
- Stage 3. Cancer cells in this stage have spread to organs as well as lymph nodes and tissues.
- Stage 4. Cancer during this stage has spread to both nearby and distant tissues, lymph nodes, and organs
Staging is not altered as mesothelioma advances. If tumors either grow or shrink, staging remains the same. People sometimes hear medical professionals refer to metastasis during which cancer spreads or grows. During the later stages of mesothelioma, mesothelioma symptoms are more easily recognized. People with late stage mesothelioma routinely have shorter life expectancies than individuals who are diagnosed with earlier-stage mesothelioma.
The Staging of Pleural Mesothelioma
Pleural mesothelioma is the only kind of mesothelioma that involves a unique staging system for mesothelioma. Some of the systems used to stage mesothelioma include the Butchart, Brigham, and TMN staging systems. While differences exist in each of these staging systems, people diagnosed at the early stages have better treatment options and a more favorable outcome.
Tumors Caused by Mesothelioma
In contrast to lung cancer, mesothelioma does not result in one central mass. Instead, mesothelioma often impacts many locations that line a person’s lungs, chest, or abdominal cavity. Besides involving many areas, the degree of thickening varies and can make it challenging to quantify the amount of cancer that is present.
Staging for Pleural Mesothelioma
For pleural mesothelioma, we rely on the International Mesothelioma Interest Group Staging or the Brigham and Women’s Hospital Staging. These systems take the extent of tumor involvement, the location of lymph nodes, and whether there is metastatic disease into consideration. The system is not utilized for either peritoneal or pericardial mesothelioma. X-rays by themselves are never utilized for mesothelioma staging. Instead, mesothelioma staging depends on information obtained from CT scans, MRIs, and/or PET scans.
The Butchart Staging System
Created in 1976, the Butchart Staging System is the oldest staging system for mesothelioma. The system is not for all types of mesothelioma but is instead only utilized to stage pleural mesothelioma. In the Butchart system, a primary tumor’s location influences the stage. The Butchart does not take some important factors into consideration including a tumor’s size, how many cancer cells are present, and the level of cancer in a person’s body. Some important details to consider about mesothelioma staging include
- Stage 1. Cancer in this stage is restricted to one side of the lung lining or pleura. Some people also have tumors in the abdominal cavity or the lining of the heart, which is also referred to as the pericardium.
- Stage 2. Cancer in this stage has spread to the chest wall and is on both sides of the lung lining or pleura. Also in this stage, cancer commonly spreads to both the lymph nodes and esophagus in a person’s chest
- Stage 3. Cancer in this stage spreads to the abdominal cavity and can be located in the lymph nodes found outside of a person’s chest.
- Stage 4. Mesothelioma spreads to distant organs in a person’s body through the bloodstream. Impacted organs can include the bones, brain, or liver.
Brigham’s Staging System
Brigham and Women’s Hospital staging was developed at the Brigham and Women’s Hospital to better characterize how staging relates to surgery. This process is meant to provide a better depiction of the anticipated outcomes after chest surgery for the illness. In 1993, while employed at the Brigham & Women’s Hospital, Dr. David Sugarbaker along with several of his coworkers created the Brigham staging system. The system’s creation was ultimately made through collaboration with the Dana-Farber Cancer Institute. While the system was first created from experience with 52 patients, the system was ultimately updated in 1998 to reflect a larger sample size. The Brigham system often relies on surgery as a method to treat mesothelioma. Some critical details to consider about how the Brigham system stages pleural mesothelioma include
- Stage 1. During this stage, cancer is not in a person’s lymph nodes. Surgical options to remove the cancerous tumor can be performed at this time.
- Stage 2. Mesothelioma in this stage spreads to a person’s lymph nodes, but surgery is still an option.
- Stage 3. Cancer in this stage has spread to the chest wall as well as the abdominal lining or heart. Surgery is not a feasible option in stage 3.
- Stage 4. Mesothelioma during this stage spreads through a person’s bloodstream. Because cancer can spread to the brain, liver, bones, and lymph nodes during this late-stage, surgery is not a feasible option.
TNM Staging System
The Tumor, Nodes, and Metastasis (TSM) system of staging was created by Pierre Denoix, a French medical doctor, during the 1940s. The system has been modified to apply to various types of cancer. The first TNM system for mesothelioma staging was created by A.P. Chahinian during the 1980s. The TSM system for mesothelioma staging is routinely updated to consider recent mesothelioma research. When it comes to classifying mesothelioma by staging, medical professionals who utilize the TSM system consider tumor size, the presence of cancer in lymph nodes, and whether cancer has metastasized to other parts of a person’s body. Some important details to consider about the TSM stages include
- Stage 1. Mesothelioma during this stage only impacts a single layer of the pleura. Mesothelioma might spread to the diaphragm, lung, or pericardium.
- Stage 2. During this stage, mesothelioma spreads to the pleura’s two layers but remains only on one side of a person’s body.
- Stage 3. Mesothelioma in this stage spreads to a person’s esophagus, chest wall, diaphragm, or lymph nodes. Cancer during this stage might also spread to nearby lymph nodes. Mesothelioma in this late stage has not yet spread to distant parts of a person’s body.
- Stage 4. The illness in this final stage has not yet spread to distant organs in a person’s bloodstream. This cancer can end up impacting the bones, brain, or liver.
What Types of Staging System Is Most Commonly Used
The TNM system is most routinely used because it considers a wider picture of lymph nodes, metastasis, and tumors. The TNM system also has additional subcategories that consider how cancer has spread, whether surgery will prove helpful, and how the pleura has been impacted.
When Staging Should Be Performed
The best type of staging occurs during surgical intervention including thoracoscopy, during which a medical professional can obtain a detailed look inside a person’s chest and biopsy areas. Lymph nodes are bean-like and have small tissue areas. The existence or absence of mesothelioma impacting lymph nodes both in and surrounding the disease is a critical part of the staging process, particularly during initial planning.
If lymph nodes are cancerous but located during surgery, they will be removed. If lymph nodes distant from the impacted area are believed to be cancerous, a person might not be viewed as a suitable candidate for surgery. Besides cancer, however, lymph nodes can be enlarged for other reasons. Often, an additional biopsy is necessary to gain an understanding of the lymph nodes involved. If the lymph nodes are located in the center of a person’s chest, a mediastinoscopy will be performed. This minor procedure is routinely performed before making a final assessment to operate even if no enlarged lymph nodes are found to exist.
The primary issue for surgery is if a tumor can be reduced to undetectable levels that are not visible or if this is not possible as the result of the disease’s presence in parts of the body that are accessible like the chest and lungs.
Circumstances also exist where surgery even if a tumor is not anticipated of being removed will need to be performed. This is often in settings where the procedure is used to relieve some substantial medical problems that prevent a person from having a better quality of life. Surgery, however, is rarely used for mesothelioma patients unless a situation exists where a substantial reduction of the disease’s burden can be performed.
Staging for Other Types of Mesothelioma
No distinct staging system exists for testicular, peritoneal, or pericardial
mesothelioma. Staging for people with peritoneal mesothelioma is made using the Peritoneal Cancer Index (PCI), which classifies diseases based on tumor size. Higher scores are assigned to more extensive cases, which often have less favorable outcomes.
Some medical professionals utilize a modified type of TNM system for staging peritoneal mesothelioma. This system of staging, however, is not yet widely accepted by the medical community. Studies have shown, however, that the TNM system predicts patient prognosis more accurately than any other system.
Due to their rarity, pericardial mesothelioma, as well as testicular mesothelioma, lack unique systems for staging. Instead, not enough data exists from case studies to accurately stage patients.
How Quickly Metastases of Mesothelioma Occurs
Mesothelioma is not common and can take between 15 to 60 years before symptoms of the disease become visible. Unfortunately, mesothelioma is often diagnosed after it has metastasized or shortly before metastases occur. Most cases of mesothelioma are diagnosed in Stage III or IV. Mesothelioma is viewed as a type of aggressive cancer because the condition develops in the abdomen or chest which is close to the vital organs in the human body and the kind of tumors seen in mesothelioma patients metastasize faster than many other types of cancer. Three types of cells in mesothelioma include epithelial biphasic, or sarcomatoid. Approximately 70 percent of mesothelioma cases involve epithelial cells, which surround organs and form tumors after being invaded by mesothelioma. Biphasic cells are found in approximately 35 percent of patients and most frequently in pleural mesothelioma.
How Staging Ends Up Influencing Treatment
The stage of mesothelioma that a person has when diagnosed directly influences what type of treatment is recommended. People with mesothelioma who are diagnosed at an early stage have the widest range of available treatment options. During the early stages, mesothelioma remains localized and a person has better health. This means that early-stage mesothelioma often allows for more aggressive treatment.
Mesothelioma treatment for people with later-stage forms of the illness often has a limited range of available treatment options. By stage 3, cancer spreads to other parts of a person’s body. Advanced-stage patients routinely receive palliative treatment to reduce symptoms and increase their life expectancy.
Palliative Treatment Options for People With Mesothelioma
Palliative treatment is given to individuals to reduce the severity of mesothelioma instead of curing the condition. These symptoms can be caused by either mesothelioma or side effects from the treatment that is given. Besides the stage, the type of mesothelioma and the type of cell influence what treatment options are used. Medical professionals also consider a person’s age and health when deciding on what type of treatment is given.
Despite staging, patients are often eligible to participate in clinical trials at mesothelioma centers. Treatments including gene therapy and immunotherapy have proven successful in clinical trials. People with mesothelioma should review the details of their case to appreciate what treatment options exist.
Life expectancy for individuals with early-stage mesothelioma is substantially
greater than for individuals with later stage mesothelioma. Chemotherapy, surgery, and radiation have proven capable of successfully treating early-stage mesothelioma.
Consider the following details about the relationship between the stage of mesothelioma that a person has and treatment options:
- Stage 1. Cytoreductive surgery is often recommended as a treatment option for people with stage 1 mesothelioma. During this early stage, surgery is routinely utilized to remove the greatest amount of cancer possible. People with pleural mesothelioma routinely receive extrapleural pneumonectomy or pleurectomy. People with stage 1 peritoneal mesothelioma can be treated with a unique type of chemotherapy called hyperthermic intraperitoneal chemotherapy. People who are diagnosed with stage 1 mesothelioma can also be treated with other types of care including intravenous chemotherapy drugs or radiation therapy.
- Stage 2. While cancer has advanced from stage 1, people with stage 2 mesothelioma still have a wide range of mesothelioma options available. Multimodal treatment is a commonly utilized type of medical care for people with stage 2 mesothelioma. This treatment involves a combination of chemotherapy, surgery, and radiation. During stage 2, surgery’s viability is influenced by metastasis and a person’s health. Multimodal plans can also incorporate emerging treatments like gene therapy and immunotherapy. What treatment options are utilized varies, though, and not all people with stage 2 mesothelioma can receive multimodal treatment. Physicians decide on what options are viable on an individual basis. Incorporated therapies vary based on individual cases and are not an option for all people with stage 2 mesothelioma.
- Stage 3. The type of medical care given to people with stage 3 mesothelioma is mainly palliative and designed to lessen the severity of symptoms. This type of treatment focuses on both prolonging a person’s life as well as improving the patient’s quality of life. During this late stage, medical providers often recommend chemotherapy and radiation. Many people with stage 3 are not suitable candidates for surgical resection. Medical providers often use minor surgical procedures to drain fluid and reduce the severity of symptoms. Both pleurocentesis and paracentesis are common types of surgery administered during this stage.
- Stage 4. Treatment methods for people with stage 4 are primarily focused on palliative treatment. During this late stage, medical professionals create treatment plans to reduce symptoms, increase a person’s life expectancy, and improve the patient’s quality of life. Some of the options used for stage 4 mesothelioma include chemotherapy, palliative surgery, and radiation.
Mediastinoscopy is a procedure used to view a person’s organs as well as the structures in the area between the lungs where lymph nodes are located. A tube is placed through an incision located above a person’s breastbone. The surgery is routinely performed to obtain a sample from the lymph nodes located on the right side of a person’s chest. Surgery is rarely indicated in mesothelioma unless a substantial reduction of the disease’s burden can be performed.