Staging of Mesothelioma

Staging of


Once a diagnosis of mesothelioma has been made, it is helpful for the doctor to determine the stage of the disease. The stage describes the size and position of the cancer and whether or not there is evidence that it has spread to nearby tissues or to other, more distant, sites.

Staging can be helpful in assessing prognosis, in making recommendations for treatment and in assessing and comparing the results of treatment. However, staging mesothelioma is difficult, the tumour is rarely present in a measurable manner.  

Different systems have been established for staging mesothelioma. Here is a shortened version of the International Mesothelioma Interest Group (IMIG) staging system: 

Stage 1

Disease limited to the pleura only on one side of the chest. 

Stage 2

Disease limited to the pleura on one side of the chest but the cancer cells have extended from the pleura into the underlying lung tissue or muscle of the diaphragm. 

Stage 3

The cancer has either spread beyond the pleura to glands in the chest and/or has advanced deeper into the tissues surrounding the pleura. 

Stage 4

The cancer has spread to distant organs or tissues or invaded deeply into tissues close to the pleura e.g. across the diaphragm into the abdomen, into the pleura of the opposite lung or into the spine or heart muscle. 

In order to stage the extent of disease a CT scan is usually carried out and may be all that is required. Other scans that are occasionally used in some centres include Magnetic Resonance Imaging (MRI), Ultrasound Scan (USS) and Positron Emission Tomography (PET) scans. 

We’re here for you

For help understanding this information, or to speak to a nurse about a new diagnosis, please call our Freephone Support Line on 0800 169 2409. 

    I wanted to pass on how much we appreciated your care, support and good spirits over the past 18months.   Dad & I have also really enjoying being part of the Mesothelioma Support Group; we have been very grateful for the informative, supporting and social side that it brought into our journey. 

    (3 minutes)