Staging

Mesothelioma Staging

Staging cancer helps doctors and specialists determine how far the disease has advanced. Information gained during staging is also important for determining the type of treatment a given patient will receive. Different types of treatment tend to be used in different stages.

Basic Staging Information

During the process of diagnosing mesothelioma, your doctor or specialist must determine the extent that the cancer has spread within the affected area and whether it has metastasized (spread to distant locations via the bloodstream). To do this, you will undergo imaging procedures such as x-ray, MRI scan, CT scan, and PET scan, which create detailed images of the inside of the body. Your specialist can then “read” these images to determine where cancer is located, and how large tumors are. Based on this information, cancer is staged, and this information is used to determine the best course of treatment.

Mesothelioma cancers, and all other cancers, are broken down into four basic stages.

Basic Stage One: The cancer is localized to one small section of the chest or abdomen (depending on the type of mesothelioma involved). The point at which the cancer first develops is called the primary tumor site.

Basic Stage Two: The cancer is said to be “advanced,” and has spread from its point of origin in the mesothelium to the organ directly beside it (in the case of pleural mesothelioma, for example, it has spread from the lining of the lungs to the lung itself).

Basic Stage Three: The cancer has spread from the mesothelium to adjacent organs, and has also spread to the lymph nodes closest to the primary tumor site.

Basic Stage Four: The cancer has metastasized to areas not adjacent to the primary tumor, usually via the bloodstream. Mesothelioma most often metastasizes to the brain, as well as other major organs.

There are various specific staging systems that are used to diagnose and treat cancers, including mesothelioma. Each of the systems uses slightly different methods of staging cancers.

Staging Systems: Butchart

The Butchart system is the oldest staging system developed, and is the one that is most commonly used to diagnose and treat mesothelioma. The Butchart system is based mainly on tumor mass, and is generally used to stage only pleural mesothelioma.

Butchart Stage One: Mesothelioma has developed in the right or left side of the chest cavity. It has not spread to the other side of the chest but may be seen in the diaphragm.

Butchart Stage Two: Cancer has been found in the lining of the heart, pleura or esophagus on both sides of the chest. Lymph nodes may be affected.

Butchart Stage Three: Mesothelioma has spread to the abdominal cavity. Lymph nodes past the chest may be affected.

Butchart Stage Four: Cancer has entered the bloodstream and spread to distant organs.

Staging Systems: TNM

The TNM System is a more modern staging system that is based on the extent of the tumor, metastasis, and lymph node involvement. This system can be used to stage both peritoneal and pleural mesothelioma.

TNM Stage One: Cancer is present in the left or right pleural membrane, and may have spread to the lung, to the lining around the heart (the pericardium), or to the diaphragm on the same side of the body. Lymph nodes are not involved at this stage.

TNM Stage Two: Mesothelioma has spread from the chest cavity to nearby lymph nodes on the same side. The cancer has also spread to the diaphragm, pericardium or the lung on the same side as the primary tumor.

TNM Stage Three: Ccancer has penetrated one or more of the chest lining, heart, esophagus, muscle, ribs, and vital organs within the chest cavity on the same side as the cancer.

TNM Stage Four: Cancer has metastasized to the opposite side of the chest from its point of origin. It may have reached the chest cavity or lungs on both sides, or has spread to vital organs in the abdomen.

Staging Systems: Brigham

The Brigham System is the newest of the four cancer staging systems. This system evaluates the stage of a cancer based on the involvement of the lymph nodes and the ability to remove tumors via surgery (this is referred to as the resectability of the tumor).

Brigham Stage One: The mesothelioma tumor is resectable and the lymph nodes are not affected.

Brigham Stage Two: The tumor is resectable, but the cancer has spread to nearby lymph nodes.

Brigham Stage Three: The mesothelioma tumor is not resectable. The cancer has penetrated the chest wall, heart, abdominal cavity, or diaphragm. Lymph nodes may or may not be affected.

Brigham Stage Four: The tumor is not resectable and the cancer has entered the bloodstream and metastasized to organs and tissues distant from the primary tumor site.