How Pleural Mesothelioma Differs from Lung Cancer

Two distinct diseases

It is natural for people without medical training to think of pleural mesothelioma and lung cancer as the same disease. Mesothelioma and lung cancer are both cancers and affect the same region of the body.  Asbestos can cause lung cancer, but it is the only known source for mesothelioma. But, mesothelioma and lung cancer differ considerably when it comes to diagnosis, treatment, and prognosis.

Origin and location of the tumor

Pleural mesothelioma is not a cancer in the lung at all.  Rather, mesothelioma is a cancer that develops in the pleura (mesothelial membrane), which is the lining around the lung.  Mesothelioma can begin in the lung lining, but it may also originate in the peritoneum (the lining of the abdomen) or the pericardium (the lining of the heart) and later spread to the pleura.

Lung cancer, on the other hand, may spread to other parts of the body, but it always originates in the lungs. Lung cancer most frequently appears as a single tumor growing in a lung, while mesothelioma cancer in the pleura spreads many smaller tumors across the surface outside the lung.  In both cases, these growths can cause pressure and pain in the chest and interfere with lung function.

Symptoms and diagnosis

Mesothelioma can be difficult to diagnose in the early stages, when it is still possible to treat with some effectiveness.  The symptoms of mesothelioma resemble those experienced by people with lung cancer, including:

• Persistent dry cough
• Chest pain
• Shortness of breath
• Difficulty breathing

Often, pleural mesothelioma is mistaken for lung cancer at first.  So, if you were ever exposed to asbestos, it is critical that you provide your doctor with a summary of your occupational history so mesothelioma can be considered as a diagnosis.

Asbestos and smoking—the relationship to lung cancer and mesothelioma

The combination of smoking cigarettes and inhaling asbestos fibers is especially deadly. Though smoking is not a risk factor for mesothelioma, medical research shows that smokers who were exposed to asbestos have a higher risk of developing lung cancer than smokers who were never exposed to asbestos.