Asbestos Exposure Mesothelioma may not develop until 15-40 years after you have been exposed to asbestos. Between 7 and 8 out of every 10 people (70 – 80%) diagnosed with mesothelioma say that have been in contact with asbestos.

In its early stages, mesothelioma does not have many symptoms.  When symptoms do develop, they are often caused by the cancer growing and pressing on a nerve or other body organ. The symptoms of the 2 main types  of mesothelioma are different.

Symptoms of Pleural Mesothelioma are:

• Pain in the lower back or the side of the chest
• A persistent cough
• Shortness of breath
• A hoarse or husky voice
• Losing more than 10% of your weight when not dieting
• Sweating and fevers
• Difficulty swallowing

These symptoms are all more likely to be caused by some other illness, rather than by mesothelioma.  But if you have these symptoms, see your doctor.  This is particularly important if you have been exposed to asbestos in the past.

Thoracoscopy
This is a small operation usually performed by a specialist surgeon. It is done under a general anaesthetic. A small cut (incision) is made in your chest wall and a thoracoscope (a telescope like instrument with a video camera attached) is inserted through the hole. Using forceps the doctor can take a biopsy. This is then sent to a laboratory for testing to see if there are any cancer cells.

Laparoscopy
This is a small operation that may be used to diagnose peritoneal mesothelioma. A tube with a camera and a light is put into your abdomen through a small cut. Your doctor can look inside to see whether there is any sign of cancer. The doctor will take samples (biopsies) of any abnormal looking areas. These will be sent to the laboratory for examination under a microscope. Laparoscopy is done under general anaesthetic. You will have a small wound with a couple of stitches. Sometimes, the camera is put in through more than one cut, so you may have more than one wound.

Stages of Pleural Mesothelioma
There are three staging systems that can be used for pleural mesothelioma. These are called the Butchart system, the TNM system and the Brigham system. In the UK the system that is mostly commonly used is the TNM system.

The Butchart staging system:
This is the oldest system. It is based on the size and spread of the primary pleural cancer. It is divided into four stages

• Stage 1 mesothelioma is in the pleura on one side only. It may have grown into the covering of the heart (pericardium) and the diaphragm
• Stage 2 mesothelioma has grown into the chest wall. It may be in the pleura on both sides. It may also have grown into the gullet (oesophagus), heart, or lymph nodes in the chest
• Stage 3 mesothelioma has spread to the abdominal cavity. It may be found in lymph nodes beyond the chest
• Stage 4 mesothelioma has spread via the bloodstream to other organs in the body such as the liver, brain or bone

This is also sometimes called the International Mesothelioma Interest Group staging system.

The TNM system is the staging system most commonly used in cancer staging generally. In mesothelioma staging, there are minor differences between the Butchart and the TNM staging systems. The TNM system describes the extent of the primary tumour (T), the absence or presence of cancer in nearby lymph nodes (N), and the absence or presence of distant metastases (M).

Once the TNM categories have been decided, this information is grouped together to give the stage. Stage 1 is the earliest stage and stage 4 is the most advanced stage.

• Stage 1 mesothelioma affects one layer of the pleura only. It may have grown into the covering of the heart (pericardium) and the diaphragm
• Stage 2 mesothelioma has spread to both layers of the pleura on one side of the body only
• Stage 3  mesothelioma has spread to the chest wall, food pipe (oesophagus) or lymph nodes on the same side of the chest
• Stage 4 mesothelioma has spread via the bloodstream to other organs in the body such as the liver, brain or bone or to lymph nodes on the other side of the chest
  

The Brigham Staging System

This is based on whether the mesothelioma can be removed by surgery and whether the lymph nodes are involved or not. Again there are four stages, which are similar to the TNM system.

• Stage 1 mesothelioma can be removed with surgery and there are no lymph nodes containing cancer cells
• Stage 2 mesothelioma can be removed with surgery but there are lymph nodes containing cancer cells
• Stage 3 mesothelioma cannot be removed with surgery because it has spread into the chest wall, heart, or through the diaphragm into the peritoneum. There may or may not be lymph nodes containing cancer cells
• Stage 4 mesothelioma has spread via the bloodstream to other organs in the body such as the liver, brain or bone