In order to make a diagnosis of mesothelioma, the physician must administer tests that evaluate the chest and abdomen.  In addition to conducting a general physical examination and documenting a thorough medical history, the doctor could order a chest x-ray and/or other visual imaging tests.  Blood tests and tissue biopsy are also frequently indicated in determining mesothelioma. 

Computerized Tomography
The physician may use CT scans as a visual aid in determining the mesothelioma diagnosis.  A CT is a test that uses computerized tomography to produce images of the body.  This technology allows for the creation of images that show slices or cross-sectional views of the body.  A material called a “contrast” may be ingested or injected in order assist in the clear imaging of abdominal or chest structures.
A CT scan takes about fifteen to thirty minutes depending on the type of equipment used for the testing.  In most cases, the patient lies still on a table with the scanner rotating around the body.  In some cases, fasting or enemas may necessary procedures prior to receiving a CT scan.

 

Magnetic Resonance Imaging
Another test that may be used for visual imaging is the MRI, or magnetic resonance imaging.  MRIs use magnetic fields to create images that are impossible with other radiographic methods.  Contrasts may also be necessary for this type of testing.
Some people cannot receive MRIs, including those who cannot comfortably lie flat or who are severely claustrophobic, since the test requires the patient to lie still in an enclosed space for about an hour.  Individuals with a cardiac pacemaker or metallic fragments implanted in the body may also need to receive an alternate type of testing. 

Positron Emission Tomography Scan
With a positron emission tomography scan, or PET scan, an image of internal organs is created to determine the body’s metabolic activity.  This diagnostic testing requires that a radioactive sugar be injected into the veins.  Prior to having a PET scan, a person may need to fast for a given time.  The test can take about an hour, not including the post-injection period required for the absorption of the radioactive material.

 

Biopsy
In addition to diagnostic imaging, surgical cell sampling may also be required in determining mesothelioma.  A biopsy is a common procedure in which a small amount of cells are removed from the affected area in order to test those cells for the presence of cancer.  Tissues are collected via various methods, including needle aspiration, in which a portion of the lump or tissue is removed through a fine needle.  When a larger sample is required, a core needle biopsy is performed, allowing the pathologist a greater amount of tissue and possibly contributing to greater accuracy of diagnosis in some cancers.  While the fine needle biopsy is faster and tends to cause less discomfort than the core needle biopsy, both procedures are routine and can be performed in an outpatient setting.
If the physician decides to remove an entire tumor, this procedure is referred to as an excisional biopsy.  This will involve the removal of a marginal area of normal tissue in addition to the diseased portion, and is usually performed on small tumors in the early stage of disease.
Other methods of sample collection include thoracoscopy, in which an incision between the ribs to accommodate a thoracoscope, and peritoneoscopy, in which the abdominal wall is incised to accommodate a peritoneoscope.  A laparotomy is another procedure that requires an incision in the abdomen; this procedure allows the surgeon to visually examine the abdominal cavity to determine health or disease.  Similarly, the thoracotomy allows the physician to inspect the chest cavity for the presence of disease through an intercostal (between the ribs) incision.
The bronchoscopy is another diagnostic procedure, wherein the physician is able to inspect the airways with a bronchoscope.  The bronchoscope is a thin tube which features a light.  During bronchoscopy, the physician may choose to collect cells for biopsy.
After cells are collected through one of the above procedures, the sample is sent to a laboratory where a cytologic examination is performed.  This examination involves the inspection of the cells with the aid of a microscope.  In microscopically examining these samples, the cellular abnormality indicative of a cancerous presence can be visually detected.