Mesothelioma symptoms can mirror those of other conditions, making a diagnosis difficult for doctors. However, because of the deadly nature of the disease, people who may have been exposed to asbestos should visit a doctor if they think they have symptoms that may be caused by mesothelioma. A doctor can perform an examination and tests and, in the case of a positive diagnosis, begin mesothelioma treatment as soon as possible.
Making a pleural mesothelioma diagnosis
Pleural mesothelioma affects the lining of the lungs, known as the pleura. Because the symptoms of the disease can mimic those of pneumonia, a doctor may first perform a physical examination or chest X-ray to rule out a respiratory infection. Listening to the patient’s breathing with a stethoscope will usually reveal muted breathing sounds in patients with mesothelioma symptoms. Tapping on the chest may also cause a dull, rather than hollow, sound.
The doctor may then take a sample of the fluid to detect the presence of cells and proteins, which can be a symptom of mesothelioma. However, as many as 85% of pleural mesothelioma cases have negative or inconclusive fluid tests. The only way a doctor can make a definitive mesothelioma diagnosis is to perform a needle biopsy or an open biopsy of the lining of the lungs. The presence of cancerous cells indicates mesothelioma.
Diagnosing peritoneal mesothelioma
Peritoneal mesothelioma is a cancer that affects the lining of the abdomen. As with the pleural form of the disease, making a peritoneal mesothelioma diagnosis can be difficult for doctors. The symptoms of the disease are similar to those of some digestive diseases. The presence of fluid in the abdomen may suggest that mesothelioma is the cause of symptoms. If so, a doctor may conduct imaging tests to learn more about the cause of the patient’s symptoms.
A CT scan may help the doctor to differentiate between the two types of peritoneal mesothelioma: wet and dry. With the dry form of the disease, one large or many small masses will be found in a localized area; with wet peritoneal mesothelioma, many smaller nodules will be spread over a larger area. The doctor may also remove fluid from the abdomen to detect the hallmarks of mesothelioma. However, because both of these techniques can lead to inconclusive results, a biopsy of abdominal tissue is the only certain way for a doctor to make a mesothelioma diagnosis.
Diagnosing pericardial mesothelioma
Pericardial mesothelioma affects the lining of the heart. The symptoms of pericardial mesothelioma often closely resemble those of cardiovascular disease, so a doctor will usually want to first conduct a CT scan or MRI to examine the heart, especially if a patient reports past asbestos exposure.
Imaging tests will typically reveal an unusual buildup of fluid around the heart, so a doctor may want to take a sample of this fluid to look for the hallmarks of pericardial mesothelioma. However, in order to make a definite mesothelioma diagnosis, the doctor will usually want to conduct a thoracoscopy. In this procedure, a small incision is made in the chest so that the doctor can use a thoracoscope (a telescope-like instrument connected to a video camera) to remove a portion of the tumor. The doctor will then perform tests on this sample to confirm his or her diagnosis.