Lung Cancer vs Mesothelioma
Asbestos exposure can lead to two types of cancer: lung cancer and mesothelioma. They both reduce lung function, cause pain, affect the chest, and can be lethal. In fact, the death rates of both types of cancer usually correlate, and in areas where there are high rates of mesothelioma deaths, there are usually also high rates of lung cancer deaths.
The two cancers are reasonably similar and this is evident in their symptoms. Usually, they lead to weight loss, fatigue, difficulty breathing, coughing, and chest pain. For those who present to a physician with these symptoms, and are known to have had asbestos exposure or they smoke or have smoked, one of the two cancers is usually suspected.
It can be difficult, not in the least for the patient, to understand how mesothelioma is different from lung cancer, particularly because they are so similar. However, significant differences exist between the two and it is important to understand these distinctions.
The Difference Between Mesothelioma and Lung Cancer
The biggest difference between the two is their development. As such:
- Mesothelioma happens when various tumors are found in a large tissue area, and they are interconnected. In advanced stages, it is impossible to distinguish between cancerous and healthy tissues. It is also for this reason that very few treatment options are available. It is generally impossible to simply remove the affected tissue, because it is so large. Radiation therapy, which is common in cancer, can only be used on a small area of tissue. Chemotherapy is slightly more effective, but usually not enough. As time goes on, the networks of tumors take over the healthy tissue. Unfortunately, because mesothelioma is generally not discovered until it is quite advanced, it is by then too late for treatment to be effective.
- With lung cancer, individual tumors start to develop with very clear boundaries. While some people do have multiple tumors if they develop lung cancer, these can be easily distinguished from healthy tissues. While lung cancer is life threatening, it is more likely to respond to treatment due to the distinct masses. If they are caught on time, they can be removed through surgery. Both radiotherapy and chemotherapy is then also more effective.
The causes and rarity of the two cancer types is also different. Mesothelioma is less common than lung cancer. It is also almost exclusively caused by asbestos exposure. Lung cancer, by contrast, can be caused by smoking or exposure to radon, pollutants, heavy metals, pesticides, and more. Smoking is one of the biggest risk factors in both types of cancer, as well. If someone has mesothelioma and smokes as well, they are much more likely to develop lung cancer too. In fact, the chance of someone who has had asbestos exposure and who smokes is 50 times greater in developing lung cancer than someone who doesn’t smoke and hasn’t had exposure.
Another significant difference is where the cancer develops. Lung cancer, as the name suggests, is inside the lungs. Mesothelioma, by contrast, is found in the lung’s lining. In fact, mesothelioma doesn’t have to develop in the lungs, as it can also be found in the lining of the testicles, heart, or abdomen.
The Similarities Between Mesothelioma and Lung Cancer
One of the reasons why the two types of cancer are so easily confused is because they have very similar early warning signs. It is vital, with both cancers, to seek help as soon as possible as the longer they are allowed continue, the more difficult is is to treat them. Furthermore, both cancers can be caused by asbestos exposure.
Looking first at mesothelioma:
- 80% of cases of mesothelioma are directly related to exposure to asbestos.
- It takes between 20 and 50 years after exposure for the condition to develop.
With lung cancer:
- 80% of lung cancer cases are directly related to smoking.
- 12% of deaths from lung cancer are related to radon exposure.
- The latency period of lung cancer is the shortest of all, being between 10 and 30 years after exposure.
Diagnosing Lung Cancer and Mesothelioma
In order for either form of cancer to be diagnosed, a number of tests are likely to be offered. These include:
- Biopsies, whereby a portion of a suspicious tissue is removed and tested for cancerous growths. This can often be done by using a needle, without any need for surgery. However, if a large sample is required, some minor surgery may be required.
- Bronchoscopy, whereby a tube is inserted into the airways and throat to determine whether there are any visible tumors. Samples can be collected for testing if abnormal growths are found.
- X-rays, which will identify ‘shadows’ on the tissue, which could be cancerous.
- Sputum cytology, which is only performed on suspected lung cancer cases. Here, a sample of thick phlegm is tested, which may show cancerous cells or blood.
Lung Cancer and Mesothelioma Treatment
The treatment that is offered for either form of cancer depends mainly on how the illness has spread. Usually, it is a combination of chemotherapy, radiation therapy, and/or surgery. Surgery will be offered if the cancer is found solely in the lung area and hasn’t affected too much of the tissue. However, different types of cancers will have different types of surgery. For instance:
- Pleural mesothelioma is surgically treated by removing some of the lung’s lining, the entire part of the lung that is affected, or even the whole lung itself.
- Lung cancer is surgically treated by removing the entire lung, a lobe of the lung, or a small portion of the lung itself.
Regardless of the type of cancer someone has, radiation therapy and chemotherapy will usually be offered. This treatment can be used to kill tumor cells and shrink growth, particularly if the tumors are still localized. This is particularly effective if used in combination with surgery. If the tumor has spread to other locations, patients may also be offered palliative care, which helps to reduce the various symptoms.
There are now also some experimental and clinical trials for treatment in both conditions. These include cryotherapy, photodynamic therapy, gene therapy, and immunotherapy. Photodynamic therapy has been shown to be reasonably effective in lung cancer in particular.
Prognosis for Mesothelioma and Lung Cancer
There are reasonable similarities between the prognosis rates for both mesothelioma and lung cancer at first, but mesothelioma develops much more quickly and has a much lower survival rate overall:
- Survival rates one year after diagnosis are 39% for mesothelioma patients and 42% for lung cancer patients.
- Survival rates ten years after diagnosis are 4% for mesothelioma patients and 10% for lung cancer patients.
What is important for someone who develops the signs and symptoms of either mesothelioma or lung cancer is to determine which one of the two illnesses they have. This is particularly true if they are or were smokers, and/or if they have had asbestos exposure. Each cancer case is unique, and an individual treatment plan has to be determined for each individual patient as well.