How Do Doctors Diagnose Mesothelioma?

The diagnosis of malignant mesothelioma cancer begins with a medical history to document the patient's symptoms and any possible asbestos exposure, followed by a complete physical examination. These steps generally are followed by a chest or abdominal X-ray or an MRI, which allows the doctor to assess the size, location and extent of the tumor in the chest or abdomen.

If fluid is present in the pleura or peritoneum, a thin needle may be used to collect a small sample of the fluid for examination. This procedure, called fine-needle aspiration, also may be used to drain the fluid to relieve symptoms such as chest pain and shortness of breath that can result from an effusion. Occasionally, mesothelioma cancer can be diagnosed with this fluid sample alone, but usually a tissue sample (biopsy) is required. The tissue sample can be obtained via thoracoscopy (for a pleural tumor) or via laparoscopy (for an abdominal tumor). In both procedures, a tubelike instrument inserted through a small incision allows the physician to view the tumor and collect a tissue sample. Patients suspected of having malignant pleural mesothelioma also may need a procedure called bronchoscopy.