Pleural mesothelioma occurs around the lungs, but it is not lung cancer. This rare cancer doesn’t form in lung tissue. It occurs in the pleura.
The pleura are membranes surrounding the lungs and lining the chest cavity. They are not part of the lungs.
Lung cancer, on the other hand, occurs inside the lungs.
Because some people confuse these two diseases, they may refer to them as one condition, “mesothelioma lung cancer.”
However, these are two unique cancers, which both affect lung function.
Key Features of Mesothelioma and Lung Cancer
Mesothelioma and lung cancer share some key features. Other aspects of these two diseases differ from one another.
- Forms in the lining around the lungs.
- Early-stage pleural mesothelioma has few symptoms.
- Caused mainly by asbestos exposure.
- Is very rare, with around 3,000 new cases per year in the U.S.
- Has a poor 5-year survival rate of around 16 percent, even when diagnosed early.
- Is treated with surgery, radiation therapy and chemotherapy, singly or in combination.
Lung Cancer Features
- Forms in the lungs.
- Early-stage lung cancer has few symptoms.
- Caused by smoking, environmental factors (air pollution, radon exposure) and asbestos.
- Is one of the most common cancers, with an estimated 234,030 new cases expected to be diagnosed in 2018.
- Has a 56 percent 5-year survival rate when diagnosed early.
- Is treated with surgery, radiation therapy, chemotherapy and immunotherapy, singly or in combination.
Patients with advanced mesothelioma, when the tumor has spread beyond the original tumor, may experience a wide range of serious symptoms.
These can include pain and tightness in the chest, shortness of breath, hoarseness and difficulty swallowing, fluid buildup in the chest or other areas, swelling in the face and arms, loss of muscle and strength, coughing up blood and night sweats and fever.
Symptoms can occur in other areas of the body, too. Examples include weight loss, lack of appetite, bloating and nausea.
Blood tests may show low red blood cell counts (anemia), changes in immune cell levels (neutropenia), elevated liver function tests and high platelet counts (thrombocytosis).
Lung Cancer Symptoms
Patients with advanced lung cancer, when the tumor has spread beyond the lungs, may experience serious symptoms, too.
These can include loss of appetite or unexplained weight loss, fatigue, headaches, bone or joint pain, loss of muscle and strength, unsteady gait or memory loss, neck and face swelling, unexplained bone fractures, bleeding and blood clots.
Your doctor may detect abnormal blood test levels, such as low red blood cell counts (anemia) and abnormal levels of minerals and proteins.
Risk Factors for Lung Cancer and Mesothelioma
Asbestos exposure is a risk factor for both lung cancer and mesothelioma. Asbestos may be a contributing factor to lung cancer, but it is almost always the sole cause of mesothelioma.
Causes of Lung Cancer
The most common cause of lung cancer is smoking. Tobacco is involved in about 90 percent of all lung cancer cases.
Radon is the second-leading cause of lung cancer. It is a naturally-occurring, odorless gas. It is involved in around 10 percent of lung cancer deaths — around 21,000 — per year.
Occupational exposure to asbestos and other carcinogens is involved in 15 percent of lung cancer cases.
A single person can have multiple risk factors. These contributors to lung cancer interact with each other, increasing the cancer risk.
Causes of Mesothelioma
The predominant cause of mesothelioma is exposure to asbestos. Historically, men have been exposed through their jobs. Working in the auto and shipbuilding industries, mining, quarrying, plumbing and pipefitting all have been associated with asbestos exposure.
Historically, women have been exposed in the home. They have come into contact through handling and laundering their spouse’s clothing or through asbestos-containing materials found in older houses.
Overlapping Risk Factors for Mesothelioma and Lung Cancer
Asbestos exposure can cause pleural mesothelioma and lung cancer.
Smoking is only associated with lung cancer. Smoking alone does not increase mesothelioma risk.
In people who have been exposed to asbestos, smoking will not further increase the risk of developing pleural mesothelioma.
On the other hand, the combination of smoking and asbestos is estimated to make the risk of lung cancer as much as 50 times worse.
In other words, people who both smoke and have a history of asbestos exposure are up to 50 times more likely to develop lung cancer than non-smokers who are never exposed to asbestos.
While quitting smoking is an important way to reduce lung cancer risk, damage from asbestos is more permanent.
Lung cancer risk drops significantly after quitting tobacco. Unfortunately, the damage from asbestos fibers is ongoing.
While the body can repair lung tissue after tobacco cessation, it cannot do so with asbestos-related harm. Once a person has been exposed to asbestos, the risk of mesothelioma continues to increase with age.
Mesothelioma and Lung Cancer Treatment
Both mesothelioma and lung cancer can be treated with radiation therapy, surgery and chemotherapy. These treatments can be combined in various ways to improve outcomes.
In many cases, radiation therapy and surgery are more effective options for treating lung cancer. This is because lung tumors tend to be more contained to one area as an individual mass.
Mesothelioma often develops as small, interconnected tumors in which cancerous tissue is interlaced with healthy tissue. This makes the disease more difficult to target with surgery or radiation.
This difference is one of the most important reasons to consult with a specialist in your specific disease.
Because mesothelioma is rare, oncologists who are not familiar with this condition may not know the best options for managing it.
Immunotherapy treatment is now FDA-approved to treat some types of lung cancer. Immunotherapy for mesothelioma is still experimental.
At this time, the standard treatment for mesothelioma does not include immunotherapy. It combines cisplatin or carboplatin chemotherapy with a targeted drug called Alimta (pemetrexed).
Because there is no cure for mesothelioma, many patients are interested in clinical trials.
An oncologist with experience treating mesothelioma can help determine which clinical trials may be a good fit for each patient.
Clinicaltrials.gov provides a way to search for mesothelioma and lung cancer clinical trials.