Mesothelioma Stages and Staging Systems

To keep a track of mesothelioma cancer, the extent of its spread and the size of tumor(s); mesothelioma has been divided into a few stages or staging systems. These mesothelioma staging systems keep a track of the development of cancer in the human body and also help in planning future treatments and the line of action for taking care of the mesothelioma patients.

An important aspect is that as pleural mesothelioma is the most common among all types of cancer and occurs frequently, these staging systems are devised to mark its stages.

The three established and recognized clinical staging systems for mesothelioma are:

• The Butchart System
• TNM Staging
• The Brigham System

Butchart Staging System

This staging system was used quiet frequently in the past. It is mainly based on the extent of primary tumor mass and divides mesothelioma into 4 stages depending upon the extent of tumor.

Stage I - In the first stage, mesothelioma is present in the right or left pleura or lining of the lungs. It can also include the lungs, pericardium or diaphragm on the same side.

Stage II – This stage marks the invasion of chest wall or esophagus, heart or pleura by mesothelioma cancer. In this stage, the lymph nodes in the chest may also become affected.

Stage III - By this stage, mesothelioma has penetrated through the diaphragm into the peritoneum, the lining of the abdominal cavity. In this stage, the lymph nodes beyond the chest may also become affected.

Stage IV – In this stage, there is evidence of distant metastases. This means the cancer might have spread to other organs of the body through blood.

TNM Staging System

Another recent staging system developed by International Mesothelioma Interest Group and adopted by the American Joint Committee on Cancer (AJCC) for mesothelioma staging is TNM staging system. T stands for tumor, N stands for spread to the lymph nodes and M is for metastasis. This system judges mesothelioma by the size of its tumor and its spread to other nearby organs.

In TNM staging, the information about tumor, lymph nodes and metastasis is staged in 4 steps. This staging system is more accurate than Butchart Staging System in diagnosing the extent of mesothelioma tumor.

Stage I – Mesothelioma has invaded either the right or left pleura lining the chest. In this stage it is restricted to only outer lining or at most a few spots. The lymph nodes are safe yet.

Stage II – Mesothelioma has now spread from the lining of the chest into the outer lining of the lung or the diaphragm or the lung itself.

Stage III - By this stage the cancer has spread to the first layer of the chest wall or the fatty part of the mediastinum – the cavity between the lungs that contains the heart, aorta, esophagus, trachea and thymus or a single spot in the chest wall, the outer covering of the heart or lymph nodes anywhere in the same side of chest.

Stage IV – This is the last stage when mesothelioma has spread into the chest wall, either muscles or ribs, through diaphragm, organs of mediastinum or spine, across the spine, other side of the chest, into the heart itself, nerves leading to arms, lymph nodes outside the chest or other organs through bloodstream.

The Brigham System

This is the latest mesothelioma staging system and works according to the resection or the surgical removal of the affected lymph nodes.

Stage I – In this stage the mesothelioma can be surgically removed as it has not yet spread to the lymph nodes

Stage II – Even though the cancer has spread to the lymph nodes, it can still be operated and removed

Stage III – In this stage, the tumor cannot be removed surgically as it has spread to the chest wall, heart, diaphragm and abdominal lining. The lymph nodes outside the chest may not necessarily be infected yet.

Stage IV – By this stage, mesothelioma has spread to other parts of the body and is in the final stages.

These three are the most commonly used clinical staging systems for mesothelioma. Aided by various medical tests and approaches, these staging systems check the advancement, size and spread of mesothelioma tumor or cancer in the human body. They help the doctors in diagnosing the patient’s stage of mesothelioma as well as planning the treatment and also preparing them for what to expect in the final stages.