TNM Staging

TNM Staging considers the three factors, Tumor size, lymph Nodes and Metastases, and can be broadly divided in 4 stages, diagnosed through chest x-rays, CAT scans, MRI’s, and endoscopic ultrasound.

Mesothelioma is an aggressive form of cancer that directly attacks the tissue surrounding the internal organs and cavities of the body, most commonly the lung (pleural), but also the heart, and stomach. This tissue, mesothelium, supplies a lubricating fluid, so that the organs move smoothly, much like the lung does during breathing. However, when cells of the mesothelium become abnormal (typically from asbestos exposure) and divide uncontrollably, cancer becomes the outcome. Then, the cancerous cells invade and penetrate nearby tissues and organs, which as it develops turns into different stages of cancer. Understanding the stage of cancer a patient suffers from, can better aid the physicians and the patients in selecting the course of treatments that offers the best result.

Unfortunately, the warning signs of mesothelioma have a latency period of about 20-50 years, that oftentimes leave patients with a diagnosis in the latter stages of cancer. Common symptoms, such as chest pain, difficulty in breathing, and painful coughing (to name a few), are misinterpreted as the flu, a cold, bronchitis, or maybe even pneumonia. Once the mesothelioma connection has been made, the first step is often to determine the stage of which the cancer has progressed. The most common staging system used is the TNM system that was created by the American Joint Committee on Cancer (AJCC).

Within the TNM system the acronym stands for:

  • T: The size of the tumor, and whether or not it has spread to nearby organs.
  • N: This refers to the involvement and potential infection of regional lymph nodes.
  • M: Metastases, which can be defined as the spread of mesothelioma to other organs or cavities.

As with other mesothelioma staging systems, like the Butchart and Brigham staging systems, there are four stages to categorize the severity of the cancer development. Specifically for the TNM staging system, the first stage is localized, whereas the last three stages are considered to be advanced.

Stage I

The mesothelioma has not spread beyond the mesothelium tissue of the chest wall, although it may also have grown into the covering of the heart and the diaphragm on the same side. This stage is typically treated through surgery, because the surgeon can removed the infected tissue, as well as some of the surrounding healthy tissue in hopes of removing all of the cancerous cells.

Stage II

In this stage, the cancer has penetrated beyond the mesothelium of the chest wall, and into the lungs and/or diaphragm. However, the lymph nodes have not been infected at this point.

Stage III

The lymph nodes with the thorax and/or the fatty part of the mediastinum have been penetrated by the mesothelioma for stage III. In addition, the diaphragm and the lining of the abdominal wall (peritoneum) may contain malignant cells.

Stage IV

Sadly, in stage IV the mesothelioma has metastases in to organs and tissues distant from the respiratory system, like the heart, spine, and esophagus, via the bloodstream.

Similarly, the TNM staging system is diagnosed through chest x-rays, CAT scans, MRI’s, and endoscopic ultrasound. Once the stage has been determined, the physician and the patient discuss the age and health of the patient in terms of the treatments that are offered. Together, they decide what course of action to take based upon how the patients chooses to spend his time with loved ones. Treatment is a very personal decision, however the medical profession has many options ranging from traditional methods to those more experimental and holistic. On the whole, the TNM staging system provides the patient a better idea of where they health stands, and what the next steps might be.