Mesothelioma Stages

Expert Fact Checked

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James Stevenson, M.D. Thoracic Medical Oncologist

Mesothelioma has four main stages.

  • Stage 1: Tumors are in the lining of one lung.
  • Stage 2: Tumors spread to nearby organs.
  • Stage 3: Tumors spread to lymph nodes and other tissues.
  • Stage 4: Tumors spread distantly.

Early stages may have more options, but treatment can improve prognosis for all stages.

01. Stages of Mesothelioma

What Are the Stages of Mesothelioma Cancer?

Doctors classify malignant mesothelioma into four main stages. Stages of mesothelioma indicate how far cancerous tumors have progressed in the body. During mesothelioma diagnosis, doctors can determine whether the cancer is stage 1, 2, 3 or 4. Stage 4 is the most advanced stage of malignant mesothelioma. At diagnosis, most patients have stage 3 or 4 mesothelioma.

The Four Stages of Mesothelioma

An illustration of the 4 stages of mesothelioma

Pleural Mesothelioma Stages

Most cancers are categorized into four stages. The four stages of pleural mesothelioma are:

  • Stage 1: The tumor is localized to the mesothelial lining and has not spread.
  • Stage 2: Cancer has spread to nearby organs, such as the lungs or diaphragm.
  • Stage 3: Cancer cells have spread to nearby tissues, lymph nodes or organs.
  • Stage 4: Cancer has spread to nearby and distant organs, tissues and lymph nodes.

Staging does not change as the disease progresses. If a tumor grows or shrinks in size, the stage remains the same. Patients may hear doctors reference metastasis when cancer grows or spreads to other parts of the body. In the later stages of the disease, symptoms are more recognizable and may worsen. Patients with stage 3 or 4 mesothelioma also tend to have shorter life expectancies than those diagnosed at an earlier stage.

Medical professionals use a variety of diagnostic tests to determine the cancer stage. Doctors evaluate tumor location, size and the extent cancer has spread during the staging process.

02. Pleural Mesothelioma Staging

How Is Pleural Mesothelioma Cancer Staged?

Staging refers to the process of categorizing malignant mesothelioma according to how much cancer is in a patient’s body. The staging process is applied to all types of cancer. Specific staging systems are often developed based on the characteristics of certain cancers. Pleural mesothelioma is the only type of mesothelioma with specific staging systems.

Mesothelioma staging occurs during the initial diagnosis. Mesothelioma doctors often use set characteristics to stage the disease. The American Joint Committee on Cancer’s AJCC Cancer Staging Manual is the most commonly cited.

The Four Stages of Malignant Pleural Mesothelioma

An illustration of stage 1 mesothelioma

An illustration of stage 2 mesothelioma

Stage 3 Mesothelioma Illustration

An illustration of stage 4 mesothelioma

Pleural mesothelioma is the only type of mesothelioma with unique mesothelioma staging systems. These systems include the Butchart, Brigham, and Tumor, Nodes and Metastasis (TNM) staging systems. These staging systems generally indicate earlier stages have better survival. But treatment options have expanded in recent years. Patients should keep an open mind about available therapies and their potential to improve prognosis.

TNM Staging System

The TNM staging system is the most commonly used staging system for pleural mesothelioma. It is periodically reviewed and updated according to new mesothelioma research. To classify pleural mesothelioma stage, doctors look at:

  • Tumor size and extent
  • Lymph node involvement
  • Metastasis to other parts of the body

Staging Pleural Mesothelioma With the TNM Staging System

Stage 1

The cancer is only affecting one layer of the pleura, or lining of the lungs. Mesothelioma may have spread to the pericardium (lining of the heart), diaphragm or lung.

Stage 2

Mesothelioma has spread to both layers of the pleura but is still localized to one side of the body. Tumors may have spread to nearby lymph nodes.

Stage 3

Mesothelioma has spread to other tissues or organs, like the chest wall, esophagus or diaphragm. The cancer may have also spread to nearby lymph nodes on both sides of the body. Tumors have not spread to distant parts of the body at this stage.

Stage 4

Mesothelioma has spread to more distant organs through the bloodstream. The cancer may impact the liver, bones or brain.

The TNM system also breaks down the four stages even further to include stages 1A, 1B, 3A and 3B. This update was intended to make it easier to estimate mesothelioma prognosis. The additional stages can also help doctors choose the most effective treatment options for each patient.

Other Pleural Mesothelioma Staging Systems

There are other systems for staging mesothelioma, although medical professionals rarely use them today. These systems were historically used for staging mesothelioma but have now largely fallen out of use.

Butchart Staging System

Proposed in 1976, the Butchart System is the oldest formal mesothelioma staging system. The system is only used to stage pleural mesothelioma. In this system, the location of the primary tumor mass determines the stage. This mesothelioma staging system does not take into account tumor size or overall level of cancer present.

Brigham Staging System

In 1993, while working at the Brigham & Women’s Hospital, Dr. David Sugarbaker and several colleagues developed the Brigham staging system. They created the system through collaboration with the Dana-Farber Cancer Institute.

Fact: The Surveillance, Epidemiology and End Results (SEER) Program from the National Cancer Institute (NCI) has its own simple staging system. Doctors do not typically use it, but researchers may.

What Are the Symptoms of Each Stage of Pleural Mesothelioma?

Many mesothelioma symptoms can be present at multiple stages. Some symptoms are more common in earlier stages. Some symptoms may develop in later stages.

Symptoms of Pleural Mesothelioma by Stage

Stage 1 and Stage 2 Symptoms
  • Chest pain
  • Difficulty breathing
Stage 3 and Stage 4 Symptoms
  • Chest pain
  • Difficulty breathing
  • Fatigue
  • Weight loss
General Mesothelioma Symptoms for All Stages
  • Coughing up blood
  • Difficulty swallowing
  • Dry cough
  • Fever
  • Night sweats
  • Pleural effusion
  • Pleural plaques
03. Staging Other Asbestos Cancers

Peritoneal Mesothelioma and Rare Asbestos Cancer Staging

Peritoneal, pericardial and testicular mesothelioma do not have their own unique staging systems. Doctors see fewer cases of these types of mesothelioma. So they have done less research into staging these types.

Peritoneal Mesothelioma Staging

Doctors may stage peritoneal mesothelioma patients using the Peritoneal Cancer Index (PCI). This staging system classifies the cancer according to tumor size and number. Thirteen regions of the abdomen are analyzed and assigned a numerical score. A higher combined score of these regions means more extensive cancer.

Some mesothelioma doctors may use a modified version of the TNM system to stage peritoneal mesothelioma patients. This staging system is not yet widely accepted within the medical community. However, data suggests it may predict patient prognosis more accurately than the PCI.

Pericardial and Testicular Mesothelioma Cancer Staging

Because they are rare, pericardial mesothelioma and testicular mesothelioma do not have their own staging systems. There are fewer than 30 pericardial mesothelioma diagnoses in the United States each year. Fewer than 300 cases of testicular mesothelioma have been described in medical literature. Because these types of mesothelioma are so uncommon, researchers have not developed unique staging systems for them.

Staging Other Asbestos Cancers and Conditions

Doctors use the TNM system to stage asbestos lung cancer. Other asbestos cancers, such as laryngeal cancer and ovarian cancer, follow their own staging systems.

Asbestosis is a lung disease caused by asbestos exposure, not a type of cancer. Doctors generally do not use a staging system to assess asbestosis cases. But they may assign it a grade ranging from zero to four, with four being the most severe.

04. Mesothelioma Treatment by Stage

How Mesothelioma Stage Impacts Treatment and Prognosis

Mesothelioma stage directly influences the recommended treatment options and is an important factor in a patient’s prognosis. Mesothelioma patients diagnosed at stage 1 or 2 often have the most treatment options available. During the early stages, the cancer is still localized. As a result, early-stage diagnosis typically allows for more aggressive treatments, such as surgery, and has a more favorable prognosis.

Mesothelioma treatment options for those with late-stage diagnoses may be more limited. By stage 3 or 4, the cancer has spread to other areas of the body, and patients may experience more severe or additional symptoms. Advanced-stage patients commonly undergo combination treatments that can extend survival. They may also receive palliative therapies to reduce symptoms, improve comfort and potentially extend life expectancy.

Understanding Palliative Mesothelioma Treatment

Palliative care is treatment administered with the intention of relieving symptoms. Patients diagnosed in any stage of mesothelioma can benefit from symptom relief. These symptoms may be the result of the mesothelioma cancer or side effects caused by other forms of treatment. In some cases, palliative care may extend life expectancy by up to six months.

Doctors also consider other factors when determining mesothelioma cancer treatment plans. In addition to stage, mesothelioma type and cell type affect treatment options. Doctors also commonly consider a patient’s existing conditions, age and overall health.

Regardless of stage, patients may be eligible for clinical trials at mesothelioma cancer centers. Treatments such as cancer vaccines and gene therapy have shown success in clinical trials.

Patients should discuss their individual cases with their doctors to understand all treatment options available.

Stage 1 Mesothelioma Treatment

Cytoreductive surgery (CRS) is often the recommended course of treatment for stage 1 mesothelioma patients. At this early stage, doctors perform this type of surgery to remove as much of the cancer as possible. Pleural mesothelioma patients often undergo extrapleural pneumonectomy or pleurectomy/decortication.

Stage 1 peritoneal mesothelioma patients may be treated with hyperthermic intraperitoneal chemotherapy (HIPEC). This is a form of chemotherapy often applied during or immediately following surgical procedures like CRS.

Mesothelioma patients diagnosed in stage 1 may be treated with radiation therapy. Doctors may also recommend intravenous chemotherapy drugs, such as pemetrexed and cisplatin.

Stage 2 Mesothelioma Treatment

Patients diagnosed with stage 2 mesothelioma typically have many treatment options. Multimodal treatment is a widely accepted option for stage 2 patients. Multimodal treatment plans include a combination of therapies, such as surgery, chemotherapy, immunotherapy and radiation.

Multimodal plans may also incorporate emerging treatments. However, therapies will vary according to each patient’s individual needs. Multimodal therapy may not be an option for all stage 2 patients. Doctors can recommend other effective options.

Stage 3 Mesothelioma Treatment

Treatment options for stage 3 mesothelioma patients typically focus on prolonging life and improving quality of life. At this stage, physicians commonly recommend multimodal or systemic treatments that target the whole body, like chemotherapy.

Doctors may also recommend immunotherapy. In 2020, the Food and Drug Administration (FDA) approved a combination of immunotherapy drugs to treat pleural mesothelioma. The drugs, Opdivo® (nivolumab) and Yervoy® (ipilimumab), improved survival compared to chemotherapy.

Surgery to remove tumors may involve too many risks for stage 3 patients. But physicians commonly use minor surgical procedures to drain fluid and ease symptoms. Pleurocentesis and paracentesis are common palliative surgeries administered at this stage.

Stage 4 Mesothelioma Treatment

Treatment plans for stage 4 mesothelioma patients largely focus on systemic treatments. But some patients may still benefit from surgery-based approaches. At this stage, physicians design treatment plans to manage symptoms, prolong life and improve quality of life.

Patients with stage 4 mesothelioma may undergo systemic chemotherapy, immunotherapy or palliative surgery.

Ongoing Research for All Mesothelioma Stages

Mesothelioma researchers use clinical trials to investigate new treatment options for early- and late-stage patients. For example, additional developments in immunotherapy continued through 2022, including promising results from new treatment combinations and immunotherapy drugs.

Ongoing clinical trials continue to test new treatments for all stages of mesothelioma.

05. Common Questions

Common Questions About Mesothelioma Cancer Stages

How fast does mesothelioma progress?

Mesothelioma may progress quickly once diagnosed, but symptoms can take years to develop. Mesothelioma has a long latency period, and patients may not experience symptoms for 10 to 50 years. Many factors can impact the latency period, such as age at first exposure to asbestos.

How does staging impact a mesothelioma diagnosis?

Doctors usually determine the mesothelioma stage during diagnosis. It is one of several factors that doctors consider when recommending treatment options. The stage of mesothelioma also impacts a patient’s prognosis, or the likely course of the disease.

Which staging system is used to stage pleural mesothelioma?

The TNM staging system is the most commonly used for pleural mesothelioma. The TNM system assesses tumor extent, lymph node involvement and metastasis. Doctors use this staging system to help determine the best treatment options for a patient’s case.