Mesothelioma is an asbestos-related cancer that is both highly-aggressive and malignant. It affects the mesothelial lining of certain organs and body cavities including the lungs (pleural mesothelioma), abdomen (peritoneal mesothelioma), heart (pericardial mesothelioma) and testicles (testicular mesothelioma). Stage 3 mesothelioma is quite advanced and not easily treated.

The Third Stage

Stage 3 mesothelioma is the third most-advanced stage of the cancer. Pleural, and peritoneal mesothelioma are often diagnosed at this stage, while testicular and pericardial cancer may not be diagnosed until stage 4. Stage 3 mesothelioma has begun to spread beyond the local area, having penetrated into nearby tissues such as the diaphragm or abdominal muscle but has not spread to distant organs. Cancer cells are also found in greater numbers and in more lymph nodes, further away from the original cancer site. At stage 3, the cancer must be treated aggressively but treatment options may be limited due to the size of the tumor(s) and tissues that have been infiltrated.

Major Characteristics of Stage 3 Mesothelioma

  • Cancer has penetrated into multiple layers of surrounding tissue and may be threatening other organs. It has also spread to multiple lymph nodes, with cancer cells present in many nodes that are distant from the body.
  • Symptoms at Stage 3 are likely to be significant and persistent including frequent cough, fever, chest, testicular or abdominal pain, fever, and weight loss.
  • Treatment will be largely conducted as a palliative measure to relieve symptoms and improve patient comfort, though multiple treatments may be used.

What to Expect

  • Stage 3 mesothelioma is quite advanced and symptoms may be severe and generally persist, even with symptomatic treatment.
  • Mesothelioma diagnosis of pleural, peritoneal and testicular mesothelioma will be confirmable through imaging studies such as X-ray, CT, and PET scans, though these imaging studies may be inconclusive in pericardial mesothelioma.
  • Additional diagnostic procedures may include blood testing and biopsy, depending on the location of the tumor(s). As the cancer is so advanced, it is imperative that patients diagnosed with Stage 3 mesothelioma consult a mesothelioma specialist for a second opinion to ensure that the diagnosis is correct and all treatment options are considered.
  • Curative surgeries may not be an option as the amount of tissue that would be required to be removed may be too great.       The cancer may also be threatening other organs, making the cancer inoperable. Palliative surgeries to drain fluid or reduce tumor size may be used to relieve symptoms of mesothelioma and other treatments may also be performed as palliative care including chemotherapy.
  • Radiation is not often a possible treatment at Stage 3 due to proximity of the cancer to other organs but may sometimes be possible.

Stage 3 Symptoms

Mesothelioma may not develop for many years after exposure to asbestos has occurred. Mesothelioma carries a long “latency time” of up to 20 to 50 years for disease development after exposure. In addition, symptoms may develop slowly over time or may emerge suddenly. Many cases of mesothelioma are not readily diagnosed due to the rarity of the disease, symptoms that mimic other disorders and the long latency time.

Symptoms of Stage 3 Mesothelioma are often variable in severity but can include:

  • Shortness of breath or difficulty breathing
  • Frequent and persistent cough
  • Feeling of “fullness”
  • Difficulty swallowing
  • Chest, abdominal or testicular pain
  • Swelling of abdomen or scrotum
  • Weight loss
  • Lethargy
  • Fever

Diagnosis of Stage 3 Mesothelioma

A diagnosis of mesothelioma at stage 3 carries a fairly grim diagnosis. The cancer has penetrated several layers of local tissue, perhaps into muscle walls and has spread into distant lymph nodes in greater numbers of cells. Diagnosis may be made using:

  • Medical history – a complete and thorough medical history will help to rule out other conditions and identify asbestos exposure.
  • Imaging studies – X-ray, CT scans, and PET scans will be useful in pleural, peritoneal and testicular mesothelioma but may have limited accuracy in pericardial mesothelioma.
  • Blood testing – may identify unique proteins that are released into the blood stream by cancerous mesothelioma cells.
  • Biopsy – a small amount of tissue removed through a surgical procedure may confirm cancer and help to identify the particular cell type when subjected to microscopic examination. A biopsy may not be possible or advisable in all cases, particularly in pericardial mesothelioma.

Stage 3 Treatment Options

Stage 3 mesothelioma is quite advanced and has limited treatment options. Most treatments will be aimed at palliative care to reduce symptoms and even though treatments are similar to those used in earlier stages, are not intended to be curative. One or more of these procedures may be used.

Depending upon the type of mesothelioma, Stage 3 treatment options include:

Chemotherapy – medications that are targeted to rapidly dividing cells. Though they are intended to eradicate cancer, in Stage 3 mesothelioma, chemotherapy will mainly be used to reduce tumor size and improve patient comfort. Chemotherapy may also be used along with other treatments for the same reason. Chemotherapy for Stage 3 mesothelioma may be given by IV infusion or as an oral medication.

Radiotherapy – focused waves or beams of energy may be used to kill cancer cells. Energy is focused on the tumor site in an attempt to kill cancer cells and reduce tumor size for symptom relief.   Depending upon tumor location and proximity to vital organs such as the lungs or heart, may not be appropriate. If radiation is used, it is most commonly performed to shrink tumor and not eradicate it.

Palliative treatments – treatments intended to provide relief from severe symptoms. Treatments may include chemotherapy and radiation when appropriate but will also include medications intended to relieve pain and other symptoms. In some cases, certain surgeries may be useful to drain fluid from the lung area, chest, abdomen or scrotum. These surgeries include:

  • Thoracentesis – Drainage of fluid from pleural cavity surrounding the lungs
  • Pleurodesis – Forced adhesion of the pleural cavity tissues to stop fluid buildup, generally done through irritating chemical treatment such as talc which will cause tissues to “stick” to one another
  • Paracentesis – Drainage of fluid from the abdominal area
  • Pericardiocentesis – drainage of fluid from the pericardial area surrounding the heart


Stage 3 mesothelioma is quite advanced. The cancer has invaded other tissue, including muscle walls in many cases. In addition, cancer cells have traveled to multiple, distant lymph nodes in great numbers. In most cases, the prognosis for Stage 3 mesothelioma patients is quite poor with the average survival time being 6 months to one year, though some patients live longer.

Because of the rarity of mesothelioma, many physicians, including oncologists do not have a wealth of experience in treating this type of cancer. Consultation with a mesothelioma specialist may give the patient additional options that are not readily available such as inclusion in a clinical trial.

Mesothelioma Staging Systems for Stage 3

Three “systems” are used for staging mesothelioma, any one or combination of which can be used to determine the severity of the disease.

TNM system – classification of the cancer stage based on assignment of numbers for (T) tumor size, (L) lymph node involvement and (M) for metastases. In most cases, Stage 3 TNM results will be T=2, L=2, M=0, meaning that the mesothelioma tumor is large or invasive, has spread to distant lymph nodes in great numbers but has not metastasized and begun growing tumors on distant organs

Butchart System – identifies that tumor is larger in size has penetrated into muscular tissue such as the diaphragm, abdominal wall, chest wall or beyond the testicular sac into groin muscles. It also identifies that cancer has spread to distant lymph nodes.

Brigham System – is older and identifies how far cancer has invaded local tissues beyond the mesothelium. It is also used to determine whether the tumor(s) are inoperable and unlikely to be cured, though palliative surgery may be helpful.