Stage 4 Mesothelioma

What Is Stage 4 Mesothelioma?

Stage 4 mesothelioma is the most advanced and final stage of the rare and aggressive cancer known as mesothelioma. This cancer forms in the lining of the lungs or abdominal cavity, and by stage 4 has spread significantly through the body.

Mesothelioma starts in either the:

• Pleura (the lining of the chest cavity) for pleural mesothelioma
• Peritoneum (the membrane covering the abdominal cavity) for peritoneal mesothelioma

In stage 4, surgery is generally not an option. However, treatment is available to manage symptoms, improve comfort, and potentially extend survival.

What Mesothelioma Symptoms to Expect in Stage 4

If you are experiencing these symptoms, see your doctor right away. You should be evaluated for the cause of your symptoms. This is how to receive a mesothelioma diagnosis.

Stage 4 Mesothelioma Treatment Options

Stage 4 mesothelioma treatment options include chemotherapy, immunotherapy, radiation therapy and palliative therapy. These treatment options are primarily used to manage symptoms, alleviate pain, and improve the patient’s quality of life.

In stage 4, tumors have possibly reached the liver, heart or kidneys. The spread of tumors to these vital organs – and the overall mass of the cancer in the body – makes mesothelioma surgery unlikely.

Some doctors may use surgery for selective cases of stage 4 mesothelioma. The surgery options for mesothelioma are:

• Pleurectomy with decortication (P/D) and extrapleural pneumonectomy (EPP) for pleural mesothelioma
• Cytoreduction with heated intraperitoneal chemotherapy (HIPEC) for peritoneal mesothelioma

There is still long-term survival hope for patients. Chemotherapy, radiation and some emerging therapies could shrink the disease enough to “downstage” the patient to stage 3 or stage 2. Immunotherapy, for instance, can slow or even stop tumor growth and extend life.

Chemotherapy for mesothelioma uses cancer-fighting drugs to target mesothelioma cells, shrink tumors, and slow cancer progression. The U.S. Food and Drug Administration (FDA) has approved pemetrexed and cisplatin as chemotherapy for mesothelioma. Doctors typically use these drugs together to maximize their effectiveness in controlling the disease.

Immunotherapy for mesothelioma enhances the immune system’s ability to recognize and attack cancer cells. The FDA has approved three immunotherapy drugs to treat mesothelioma:

• Opdivo (nivolumab) and Yervoy (ipilimumab) – Approved as a combination treatment for patients with pleural mesothelioma who cannot have surgery
• Keytruda (pembrolizumab) – Approved for patients with pleural mesothelioma who cannot have surgery

These treatments help slow disease progression and may improve survival outcomes in some patients. Since they are approved for people who cannot have surgery, they are top options to consider for patients with stage 4 mesothelioma.

Radiation for mesothelioma uses high-energy beams to target and destroy cancer cells while minimizing damage to healthy tissue. It can shrink tumors, slow disease progression, and alleviate symptoms.

• Radiation is primarily used for pleural mesothelioma. Most doctors do not recommend radiation for peritoneal mesothelioma due to the potential damage to vital abdominal organs.
• This therapy can help extend survival and relieve pain by reducing tumor size in the chest, making breathing easier.

Palliative mesothelioma surgery aims to relieve symptoms and improve quality of life. While not curative, these procedures can extend survival by a few months and help manage complications.

Common Palliative Surgeries for Mesothelioma:

• Pleurodesis – This procedure for pleural mesothelioma removes excess fluid from the pleural space (pleural effusion) and seals the cavity to prevent further buildup.
• Thoracentesis – This procedure for pleural mesothelioma uses a needle to drain excess fluid from the pleural cavity.
• Paracentesis – This procedure for peritoneal mesothelioma uses a needle to drain excess fluid from the abdominal cavity.
• Pericardiocentesis – This procedure for pericardial mesothelioma uses a needle to drain excess fluid from the sac surrounding the heart (pericardium).

These procedures help reduce discomfort and improve lung or organ function, enhancing the patient’s overall well-being.

Clinical trials offer access to experimental treatments that may be more effective than standard therapies. Immunotherapy, for example, has shown promise in enhancing the immune system’s ability to combat mesothelioma.

Some clinical trials target late-stage cancer, including stage 4 mesothelioma. Patients often enroll in clinical trials to access emerging treatments that could improve their life expectancy.

Prognosis

The prognosis for mesothelioma for stage 4 is typically less than one year. A study published in UpToDate reported a median life expectancy of 11 months following diagnosis.

Research in the Journal of Thoracic Oncology found that approximately 20% of mesothelioma patients are diagnosed in stage 4, while the majority are diagnosed in stage 2 or stage 3.

Several factors influence an individual’s prognosis, including cell type, overall health, age, and gender. While stage 4 mesothelioma has a poor prognosis, some patients respond well to treatment and may live longer than expected.

Second Opinion

Receiving a second opinion is critical for patients diagnosed with stage 4 mesothelioma. A second opinion from a mesothelioma specialist could reveal a different stage, more treatment options, and a better prognosis.

According to a study published in the Journal of Thoracic Oncology, around 13.5% of patients who initially receive a stage 4 diagnosis were reclassified to a lower stage. People in lower stages are more likely to be considered for surgery and clinical trials. This reassessment can positively impact treatment decisions and potential outcomes.

Mesothelioma Survivors and Stage 4

There have been a few mesothelioma survivors who were diagnosed with stage 4 cancer. One mesothelioma survivor, Alexis Kidd, is an example of why you should get a second opinion.

Alexis was diagnosed with peritoneal mesothelioma in stage 4. However, a second opinion revealed her cancer was in stage 2. With appropriate treatment, including surgery and chemotherapy, she has survived for more than 17 years as of 2025.

Her story underscores the potential benefits of getting a second opinion from a specialist and receiving treatment from experienced mesothelioma doctors.

How Each Mesothelioma Staging System Defines Stage 4

The TNM system (Tumor, Node, Metastasis) is the most widely used staging system for pleural mesothelioma. It evaluates three key factors:

• Tumor (T): Size and extent of the primary tumor
• Node (N): Degree of lymph node involvement
• Metastasis (M): Spread to distant organs

In stage 4 mesothelioma, the TNM system defines the disease as having large tumors, extensive lymph node involvement and widespread metastasis. Lymph nodes are often significantly swollen and cancer has likely spread to distant organs such as the liver, brain or other areas of the body.

The Butchart System is the oldest staging system for pleural mesothelioma. It focuses on the size of tumors and where they’ve spread. In stage 4, the mesothelioma cells have spread through the bloodstream to distant organs, such as the liver or brain.

The Brigham System focuses on whether surgery is an option. It was designed by esteemed mesothelioma specialist Dr. David Sugarbaker when he worked at Brigham and Women’s Hospital in Boston. Since stage 4 mesothelioma has spread to distant organs and lymph nodes, this system does not consider stage 4 mesothelioma to be operable.

The peritoneal cancer index (PCI) is a staging system for peritoneal mesothelioma. It classifies how much tumors have spread within the abdominal cavity.

The abdomen is split into 13 regions, and each region receives a score between 0 and 3. The score is based on the extent of tumors in the region, with 3 signaling that tumors cover the majority of the region and 0 meaning that tumors aren’t present.

PCI scores between 31 and 39 correlate to stage 4 mesothelioma.