Diagnosis of malignant mesothelioma

Non-invasive procedures

Non-invasive tests that may be performed to aid in the diagnosis and staging of malignant mesothelioma include the following:

• Blood test. Various blood tests may be taken, to determine if the patient is anemic, if his platelet level is normal, whether there are any chemical imbalances in the body, or if there are indications that the cancer has spread to other organs.
• Additional imaging studies: CT (computerised tomography) and MRI (magnetic resonance imaging) take cross-sectional images to better show abnormalities seen on plain x-ray. Patient is required to lie in large tubular structure while x-rays (CT) or magnetic fields (MRI) are aimed at area of concern. Painless, but may be disconcerting, especially if the patient is claustrophobic. MRI procedure may be very loud. Ultrasonography uses sound waves to visualize structures, and may be used to characterize a pleural effusion and guide a biopsy.
• Bone scan (to determine local or distant bony invasion). Usually involves injection of a short-lived radioactive material that travels to sites of increased bone turnover (which occur with spread of cancer to bones). Images are then taken using a special camera, with 'hot spots' indicating areas of cancerous spread. (Other types of radioactive imaging has occasionally been used to differentiate asbestos-related benign from malignant pleural disease.)
• Lung function test. This usually requires the patient to blow into a special instrument, from which various measurements can be taken to determine how well the lungs are performing.