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Stages of Malignant Mesothelioma

After malignant mesothelioma has been diagnosed, tests are done to find out if cancer cells have spread to other parts of the body.

The process used to find out if cancer has spread outside the pleura or peritoneum is called staging. The gathered from the staging process determines the stage of the disease. It is important to know whether the cancer has spread in order to plan treatment.

The following tests and procedures may be used in the staging process:

  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of the chest and abdomen, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  • PET scan (positron emission tomography scan): A procedure to find cancer cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
  • Endoscopic ultrasound (EUS): A procedure in which an endoscope is inserted into the body. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. This procedure is also called endosonography. EUS may be used to guide fine-needle aspiration (FNA) biopsy of the lung, lymph nodes, or other areas.
  • Laparoscopy: A surgical procedure to look at the organs inside the abdomen to check for signs of disease. Small incisions (cuts) are made in the wall of the abdomen and a laparoscope (a thin, lighted tube) is inserted into one of the incisions. Other instruments may be inserted through the same or other incisions to perform procedures such as taking tissue samples to be checked under a microscope for signs of disease.
  • Lymph node biopsy: The removal of all or part of a lymph node. A pathologist views the lymph node tissue under a microscope to check for cancer cells.
  • Mediastinoscopy: A surgical procedure to look at the organs, tissues, and lymph nodes between the lungs for abnormal areas. An incision (cut) is made at the top of the breastbone and a mediastinoscope is inserted into the chest. A mediastinoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue or lymph node samples, which are checked under a microscope for signs of cancer.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

  • Tissue. The cancer spreads from where it began by growing into nearby areas.
  • Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
  • Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

  • Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
  • Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of cancer as the primary tumor. For example, if malignant mesothelioma spreads to the brain, the cancer cells in the brain are actually malignant mesothelioma cells. The disease is metastatic malignant mesothelioma, not brain cancer.

The following stages are used for malignant mesothelioma of the lung:

Stage I

Stage I is divided into stages IA and IB:

  • In stage IA, cancer is found in the inside lining of the chest wall on one side of the chest. On the same side of the chest, cancer may also be found in one or more of the following:
    • The thin layer of tissue that covers the lung.
    • The thin layer of tissue that covers the organs between the lungs.
    • The thin layer of tissue that covers the top of the diaphragm.
  • In stage IB, cancer is found in the inside lining of the chest wall, and in each of the thin layers of tissue that cover the lung, the organs between the lungs, and the top of the diaphragm on one side of the chest. On the same side of the chest, cancer has also spread into one or more of the following:
    • Diaphragm.
    • Lung tissue.
    • Tissue between the ribs and the inside lining of the chest wall.
    • Fat in the area between the lungs.
    • Soft tissues of the chest wall.
    • Sac around the heart.

Stage II

In stage II, cancer is found in the inside lining of the chest wall on one side of the chest. On the same side of the chest, cancer may also be found in one or more of the following:

  • The thin layer of tissue that covers the lung.
  • The thin layer of tissue that covers the organs between the lungs.
  • The thin layer of tissue that covers the top of the diaphragm.

Cancer has spread to lymph nodes along the center of the chest on the same side of the chest as the tumor.

or

Cancer is found in the inside lining of the chest wall, and in each of the thin layers of tissue that cover the lung, the organs between the lungs, and the top of the diaphragm on one side of the chest. On the same side of the chest, cancer has also spread into one or both of the following:

  • Diaphragm.
  • Lung tissue.

Cancer has spread to lymph nodes along the center of the chest on the same side of the chest as the tumor.

Stage III

Stage III is divided into stages IIIA and IIIB.

  • In stage IIIA, cancer is found in the inside lining of the chest wall, and in each of the thin layers of tissue that cover the lung, the organs between the lungs, and the top of the diaphragm on one side of the chest. On the same side of the chest, cancer has also spread into one or more of the following:
    • Tissue between the ribs and the inside lining of the chest wall.
    • Fat in the area between the lungs.
    • Soft tissues of the chest wall.
    • Sac around the heart.

    Cancer has spread to lymph nodes along the center of the chest on the same side of the chest as the tumor.

  • In stage IIIB, cancer is found in the inside lining of the chest wall, and may also be found in the thin layers of tissue that cover the lung, the organs between the lungs, and/or the top of the diaphragm on one side of the chest. On the same side of the chest, cancer may have also spread into one or more of the following:
    • Diaphragm.
    • Lung tissue.
    • Tissue between the ribs and the inside lining of the chest wall.
    • Fat in the area between the lungs.
    • Soft tissues of the chest wall.
    • Sac around the heart.

    Cancer has spread to lymph nodes above the collarbone on either side of the chest or cancer has spread to lymph nodes along the center of the chest on the opposite side of the chest as the tumor.

    or

    Cancer is found in the inside lining of the chest wall, and in each of the thin layers of tissue that cover the lung, the organs between the lungs, and the top of the diaphragm on one side of the chest. Cancer has also spread to one or more of the following:

    • The chest wall and may be found in the rib.
    • Through the diaphragm into the peritoneum.
    • The tissue lining the chest on the opposite side of the body as the tumor.
    • The organs in the area between the lungs (esophagus, trachea, thymus, blood vessels).
    • The spine.
    • Through the sac around the heart or into the heart muscle.

    Cancer may have spread to lymph nodes.

Stage IV

In stage IV, cancer has spread to the tissue covering the lung or the lung on the opposite side of the chest, peritoneum, bones, liver, lymph nodes outside the chest, or to other parts of the body.

Malignant mesothelioma can recur (come back) after it has been treated.

The cancer may come back in the chest or abdomen or in other parts of the body.

This information is not intended to replace the advice of a doctor. Navigating Care disclaims any liability for the decisions you make based on this information. This information was sourced and adapted from Adapted from the National Cancer Institute's Physician Data Query (PDQ®) Cancer Information Summaries on www.cancer.gov.