Diagnosis of mesothelioma usually begins with a physical exam. During the exam, the doctor will pay special attention to the patient's symptoms as well as how much contact they have had with asbestos. After the exam, the doctor will conduct tests to determine the cancer's stage.
Chest X-rays and CT scans provide an image of what is going on inside the lungs and chest. These images can show if fluid has begun to build up in the chest or lungs and show if the cancer has spread to other areas of the body. CT scans can help determine the stage of cancer.
If fluid has begun to build up in the chest or lungs, the doctor may take a sample of the fluid to test it for lung cancer. When lung cancer is present, the body creates a substance, called an antigen, that tells the immune system to respond. High levels of this specific antigen, known as carcinoembryonic antigen (CEA), are a sign of lung cancer.
If mesothelioma or lung cancer is suspected, the doctor will take a biopsy, a small tissue sample using a needle. The sample will be studied under a microscope for signs of cancer.
- Stage I - the cancer is limited to one area of the tissue lining.
- Stage II - the cancer has spread past the lining of the chest to the diaphragm or to a lung.
- Stage III - the cancer has spread to other organs and tissues within the chest, possibly to nearby lymph nodes.
- Stage IV – this is advanced cancer that has spread more completely through the chest. The cancer may have also spread to other areas of the body, such as the brain, liver and lymph nodes.