Mesothelioma Stages

Doctors have traditionally determined the severity of a patient’s cancer in terms of “stages.” The stage of an individual’s cancer determines the life expectancy and prognosis of the victim. Through the years, many staging models have been created, taking into consideration many factors such as lymph node involvement and metastases.

When a diagnosis is made, one of the first things the oncologist attempts to do is “stage” the cancer, a step that will help him determine the best cause of treatment. Unfortunately, malignant mesothelioma – because of its nature – is often not diagnosed until Stage 3 or 4 when symptoms finally begin to appear. That allows for far fewer treatment options.

Currently, there are three widely-accepted staging systems for malignant pleural mesothelioma but no systems for measuring the rarer forms of the disease – peritoneal, pericardial and testicular mesothelioma.

Butchart System

The system most commonly used by doctors to stage malignant pleural mesothelioma is the Butchart System, the first one devised to measure this aggressive form of cancer. It is based on the mass (or size) of the tumor and is divided into four stages.

  • Stage 1 – The mesothelioma has affected either the right or left side of the chest cavity/pleura and may also be found in the diaphragm.
  • Stage 2 – The mesothelioma has been found in the pleura on both sides of the body and may have also spread to the stomach, heart and esophagus on both sides. The lymph nodes may or may not be affected.
  • Stage 3 – The mesothelioma has reached the peritoneum – the abdominal cavity – and may involve the lymph nodes past the chest.
  • Stage 4 – The mesothelioma has spread to other organs of the body and has entered the blood stream.

TNM System

Also divided into four stages, the more modern TNM System of cancer staging is based on extent of the tumor, metastases, and the involvement of the lymph nodes.

  • Stage 1 – The cancer is present in the right or left pleura and may have spread to the lung, diaphragm or pericardium (lining of the heart). Lymph nodes are not involved at this point.
  • Stage 2 – The mesothelioma has spread from the pleura on the side at which is located to the lymph node closest to the affected area. It has also spread to the lung on the same side as well as the diaphragm and pericardium.
  • Stage 3 – The malignant mesothelioma has now entered heart, esophagus, muscle, ribs and vital organs within the chest cavity on the same side as the cancer. The lymph nodes may or may not be involved at Stage 3.
  • Stage 4 – At this point, the cancer has spread to the pleura and lymph nodes on the opposite side of where the primary tumor was located. It may have also spread to the other lung as well as the abdomen.

Brigham System

This is the newest staging system for malignant mesothelioma. It considers resectability (whether or not the tumor can be surgically removed) as well as lymph node involvement. That means it is not used very often as most mesothelioma patients are not candidates for surgery. It is divided into four stages.

  • Stage 1 - The tumor is still considered resectable and the lymph nodes are not yet affected.
  • Stage 2 - The tumor is still resectable but the lymph nodes are now involved.
  • Stage 3 – The tumor is no longer resectable and the mesothelioma has spread to the heart, chest wall, abdominal cavity or diaphragm. Lymph nodes may or may not be affected.
  • Stage 4 - The tumor is not resectable and the cancer has completely metastasized.

Tests for Staging

A simple physical examination cannot determine the stage of malignant mesothelioma. In most cases, sophisticated imaging tests will be involved, including MRIs, CT scans or PET scans. Biopsies may also be used.

To learn more about the staging systems and how staging affects mesothelioma treatment options, please fill out the form on this page to receive a comprehensive packet in the mail that details current treatment options, top mesothelioma doctors and cancer centers, and much more.