Diagnosis of mesothelioma is a difficult procedure. It is to analyze the symptoms in the initial stages. The symptoms of this rare disease make the diagnosis very difficult even to a doctor, since the symptoms would be very similar to other common diseases in the early stages of this deadly disease. Delay in the diagnosis is very common in most of the cases. As a matter of fact these symptoms can appear as non-specific to both the patient and their doctors.

A careful assessment is needed in the diagnosis of mesothelioma which relates both the clinical and radiological findings. The tissue biopsy is also confirmed carefully along with the above factors. The reviewing of the patients medical history can be very helpful to diagnose mesothelioma. Observation of the disease and the history includes details such as the patients asbestos exposure, the complete physical examination, x-ray results of the chest and abdomen, and the lung function tests.

A Computerized Tomography (CT) scan or Magnetic Resonance Imaging (MRI) scan may also be taken at this level. If the preliminary test results prove suspicious, then a biopsy is performed for confirming the diagnosis. The location of the cancer can be determined with the help of performing the biopsy. If the biopsy test confirms the presence of mesothelioma, the stage of the cancer is then determined. A series of tests are performed to determine the amount of cancerous cells that have spread.

If the test shows that the cancerous cells are not developed beyond the membrane, then the disease is considered to be localized. During this diagnosis procedure, various tests are performed such as the imaging tests, which includes the use of x-rays; CT (Computed Tomography) scans; MRI (Magnetic Resonance Imaging); PET (Positron Emission Tomography); bronchoscopy or mediastinoscopy, used to look into the affected area; cytology, used to test the pleural fluid after it is removed by a needle; thoracoscopy, used to look directly into the tumor; needle biopsy; and open biopsy. Those are the major tests that are performed during the mesothelioma diagnosis.