Tests and diagnosis of mesothelioma
If you have signs and symptoms that might indicate mesothelioma, your doctor will conduct a physical exam to check for any lumps or other unusual signs. Your doctor may order imaging scans, such as a chest X-ray or a computerized tomography (CT) scan of your chest or abdomen, to look for abnormalities.
It's not uncommon for mesothelioma to be misdiagnosed initially because mesothelioma is rare, and its signs and symptoms aren't specific. Your doctor will likely rule out other more common conditions before considering mesothelioma.
Biopsy
Biopsy, a procedure to remove a small portion of tissue for laboratory examination, is the only way to determine whether you have mesothelioma. Depending on what area of your body is affected, your doctor selects the right biopsy procedure for you. Options include:
- Fine-needle aspiration. The doctor removes fluid or a piece of tissue with a small needle inserted into your chest or abdomen.
- Thoracoscopy. Thoracoscopy allows the surgeon to see inside your chest. In this procedure, the surgeon makes one or more small incisions between your ribs. A tube with a tiny video camera is then inserted into your chest cavity — a procedure sometimes called video-assisted thoracoscopic surgery (VATS). Special surgical tools allow your surgeon to cut away tissue for testing.
- Laparoscopy. Laparoscopy allows the surgeon to see inside your abdomen. Using one or more small incisions into your abdomen, the surgeon inserts a tiny camera and special surgical tools to obtain a small piece of tissue for examination.
- Thoracotomy. Thoracotomy is surgery to open your chest between the ribs to allow a surgeon to check for signs of disease. He or she removes a sample of tissue for testing.
- Laparotomy. Laparotomy is surgery to open your abdomen to allow a surgeon to check for signs of disease. He or she removes a sample of tissue for testing.
The tissue sample is analyzed under a microscope to see whether the abnormal tissue is mesothelioma and what types of cells are involved. The type of mesothelioma you have determines your treatment plan.
Staging
Once mesothelioma is diagnosed, your doctor orders other tests to determine the extent, or stage, of the cancer. Imaging tests that may help determine the stage of your cancer include:
- Chest X-ray
- CT scans of the chest and abdomen
- Magnetic resonance imaging (MRI)
- Positron emission tomography (PET)
Once the extent of pleural mesothelioma is determined, a stage is assigned. Formal stages aren't available for other types of mesothelioma because these types are rare and aren't well studied. The stages of pleural mesothelioma are:
- I. Stage I pleural mesothelioma is considered localized cancer, meaning it's limited to one portion of the lining of the chest.
- II. Stage II mesothelioma may have spread beyond the lining of the chest to the diaphragm or to a lung.
- III. Stage III mesothelioma may have spread to other structures within the chest and may involve nearby lymph nodes.
- IV. Stage IV mesothelioma is an advanced cancer that has spread to distant areas (metastasized). Mesothelioma most commonly spreads (metastasizes) to the brain, lymph nodes in the chest and areas of the lung that are away from the tumor.
Content provided by Mayo Foundation for Medical Education and Research (MFMER)
