Lung Cancer and Asbestos Exposure
At the moment, lung cancer is the second leading cause of death in the United States, exceeded only by heart disease. Every year, over 150,000 people lose their lives to this illness, whereas 200,000 others receive a lung cancer diagnosis. According to the American Cancer Society, the lifetime chance of developing lung cancer is 1 in 14 for men and 1 in 17 for women. Lung cancer represents approximately 14% of new cancer cases. While the primary cause of this malignant disease is tobacco smoking, with over 80% of patients being former or current smokers, asbestos exposure can also be responsible for lung cancer.
It is estimated that 4% of lung cancer cases occur due to asbestos exposure, which results in 4,800 victims in the U.S. annually. A causal relationship between lung cancer and asbestos exposure was first suggested by medical researchers in 1935 and seven years later, the National Cancer Institute confirmed it. Moreover, in 1986, OSHA deemed lung cancer as the most serious health risk employees working with asbestos were facing. As every disease stemming from asbestos exposure, lung cancer also has a long latency period, developing only within 15 to 35 years of initial contact with the toxic mineral.
According to the Helsinki criteria, which were set by medical professionals in 1997 with the purpose of determining whether certain lung cancer cases were related to asbestos exposure, the likelihood of being affected by lung cancer increases with 4% after each asbestos exposure. Cigarette smoking also influences the risk of developing lung cancer to a tremendous extent in individuals exposed to asbestos – smokers with a history of asbestos exposure are 50 to 90 times more prone to developing lung cancer than non-smokers.
How Does Asbestos Exposure Cause Lung Cancer?
The inhalation of airborne asbestos fibers may lead to lung cancer over the years. Due to their microscopic size and rough texture, asbestos fibers can easily attach themselves to lung tissue after a person breathes them in. The size of asbestos fibers may actually determine whether the exposed individual will develop lung cancer or mesothelioma, according to recent findings. While asbestos fibers with a 3-millimeter length tend to become embedded in the outer lining of the lung, those of 5 millimeters or longer are more likely to reach the inside of the organ. Thus, shorter asbestos fibers are believed to cause mesothelioma, whereas longer ones are linked to lung cancer.
Following the inhalation of asbestos fibers, inflammation and tissue scarring will gradually occur in the lungs, which might, in turn, give way to lung cancer. As is the case with mesothelioma, the risk of developing lung cancer after asbestos exposure also depends on factors such as:
- the amount of asbestos fibers inhaled
- the duration of exposure
- whether you already suffer from a type of lung disease
Individuals who were exposed to asbestos in the workplace are the most susceptible to lung cancer, since they were typically in contact with enormous amounts of asbestos and would regularly breathe in toxic fibers over the course of several years. Some of the occupational groups at high risk include construction workers, plumbers, paper mill workers, auto mechanics, insulators, textile workers, and roofers. However, there is no general rule when it comes to this aspect, as there have been people whose health was dramatically affected after a single asbestos exposure.
Lung Cancer Types and Symptoms
Depending on the size of the cells which make up the tumor, lung cancer can be of two types: non-small cell lung cancer and small cell lung cancer. Each type has its own particularities and spreading pattern, as well as staging system.
This is the most common type of lung cancer, accounting for over 80% of all diagnosed cases. It usually progresses and spreads at a slower pace than its small cell counterpart. The size of the primary tumor and whether cancer has spread to other organs or regions of the body are the factors which determine the stage of non-small cell lung cancer. There are multiple subtypes of non-small cell lung cancer, such as:
- adenocarcinoma – responsible for approximately 30% of lung cancer cases, this form begins developing in the lining of the lungs and the tumor has gland-like properties
- squamous cell carcinoma – this subtype is accountable for a little under 30% of all lung cancer diagnoses and starts growing in the flat cells which line the passages of the respiratory system
- large cell carcinoma – the most rapidly growing subtype of non-small cell lung cancer, which represents approximately 9% of all cases
- large cell neuroendocrine tumors – another fast-growing subtype which accounts for 2% of the entire number of lung cancer diagnoses
While neuroendocrine tumors are also involved in small cell lung cancer, their cells have – as the name suggests – a smaller size. Also known as oat cell cancer, this form occurs in 15-20% of all lung cancer cases and tends to spread very rapidly.
Until recently, it was believed that the type of lung cancer asbestos exposure usually causes is adenocarcinoma. However, further medical research did not find a particularly high prevalence of adenocarcinoma among asbestos victims suffering from lung cancer, thereby revealing that asbestos exposure may result in any type of lung cancer, both small and non-small cell.
The symptoms most frequently associated with lung cancer, regardless of its type, include:
- a chronic cough, which may be dry or mucus-producing
- shortness of breath
- chest pain which becomes more intense with coughing, taking deep breaths or laughing
- unexplained weight loss
- recurring respiratory infections such as pneumonia or bronchitis
- loss of appetite
- coughing up blood
- difficulty swallowing
- nail clubbing
Nevertheless, approximately 25% of people who have lung cancer will not experience any symptoms before the disease reaches advanced stages. For this reason, if you have a history of asbestos exposure, it is crucial to undergo annual screenings. Doing so will help you avoid having your illness detected when it is too severe. Timely diagnosis is vital when it comes to asbestos-related diseases, as they typically progress at a fast pace, the more so if a form of cancer is involved.
When lung cancer is advanced, people may notice additional symptoms, such as:
- changes concerning the nervous system, if cancer spread to the brain or the spinal cord, such as numbness of a leg or arm, dizziness, balance problems or seizures
- bone pain
- yellowing of the skin and eyes (jaundice), if the liver was also affected by cancer
- lumps in the neck or above the collarbone, if cancer spread to the skin or the lymphatic system
Diagnosing Asbestos-Related Lung Cancer
The latency period is one of the key-factors medical experts consider when they try to determine whether a case of lung cancer is related to asbestos exposure. Accordingly, if a patient with a history of asbestos exposure developed lung cancer within 15 to 35 years of their first contact with airborne fibers, their illness is likely to have been caused by it. Another essential clue when it comes to establishing a connection between asbestos exposure and lung cancer is the presence of tissue scarring in the lungs – the tell-tale sign of asbestos-related lung cancer.
Unlike lung cancer which ensues as a result of other causes, such as tobacco smoking or radon exposure, asbestos-related lung cancer will always be accompanied by tissue scarring due to the irritating nature of asbestos fibers. The occurrence of tissue scarring in the lungs can be identified using the following diagnostic tools:
a chest X-ray
which can provide your physician with basic information concerning the condition of your lungs
a CT scan
during which your doctor will be able to thoroughly examine your lungs, as well as detect small lesions and abnormalities a chest X-ray fails to reveal
Nevertheless, the ultimate test with regard to confirming a causal relationship between asbestos exposure and lung cancer is a biopsy. During this procedure, a sample or fluid or tissue is collected from the lungs, which will subsequently be analyzed by a pathologist. Not only is a biopsy the most reliable way of confirming a lung cancer diagnosis, but it can also reveal the presence of asbestos fibers in the lungs. There are two types of biopsy, depending on what the collected sample consists in:
– which can be performed by using either a surgical or a non-surgical approach and during which a sample of tissue is collected from the lungs
- during which your doctor will be able to thoroughly examine your lungs, as well as detect small lesions and abnormalities a chest X-ray fails to reveal
While both fluid and tissue biopsies entail highly accurate results, the latter are thought to be slightly more reliable, since the amount of cancer cells present in tissue samples is usually larger, which makes it easier for pathologists to properly examine them and identify their particularities. As far as surgical biopsies are concerned, there are multiple ways the surgeon can collect tissue samples, including numerous minimally invasive approaches such as:
- bronchoscopy – a thin, flexible tube equipped with a small camera is inserted through the nose or mouth into the lungs, by way of which the surgeon examines the organs and collects samples of tissue
- mediastinoscopy – a procedure which entails a thin, flexible tube with a camera attached being inserted in the chest cavity through a small incision made above the breastbone for the same purposes
- thoracoscopy – this surgical approach consists in a thin, flexible tube, also equipped with a camera, being inserted through a small incision in the chest wall so as to allow the surgeon to assess the condition of your lungs and collect samples of tissue
Regardless of the cause of the illness, diagnosing lung cancer is a very complex process which may extend over several weeks. Multiple tests will be necessary in order to receive a reliable diagnosis and allow specialists to determine essential aspects such as the type of cancer cells and the stage of the illness, as well as the most effective treatment approach for you. In addition to imaging tests and biopsies, one or more of the following diagnostic tools may be used alongside:
- a series of blood tests
- gene mutation testing
- a sputum cytology – a test whose purpose is to identify cancer cells in samples of mucus
- bone scans
Because asbestos-related lung cancer bears a very close resemblance to mesothelioma in terms of tumor appearance and symptoms, most oncologists find it challenging to distinguish one from the other. The expertise of a specialist is therefore vital, as only a medical professional with vast experience in identifying illnesses which stem from asbestos exposure will be able to assign you a correct diagnosis. Since the rate of misdiagnosis is extremely high among asbestos victims, we also encourage you to seek a second and even a third opinion from equally or more qualified specialists if you have a history of asbestos exposure and experience worrisome symptoms.
How Is Asbestos-Related Lung Cancer Treated?
As you have certainly noted hitherto, lung cancer is a complex disease with numerous key variables, from cell type to stage. Consequently, regardless of the cause of their illness, each patient will receive individualized treatment consisting in one or more of the following:
The aim of lung cancer surgery is to remove the malignant tumor, as well as the surrounding tissue which has been affected by cancer. Depending on the extent of resection, there are three surgical procedures for lung cancer:
- resection, the removal of the tumor and the nearby lung tissue
- lobectomy, which entails the resection of a whole lobe of the lung
- pneumonectomy, during which the lung is removed in its entirety
Unfortunately, because timely detection is rare, the majority of lung cancer patients are not eligible for surgery. The advanced stage of cancer is what mostly prevents patients from undergoing surgery, which is quite aggressive and would imply serious risks if opted for. Moreover, since most people who develop lung cancer are over the age of 65, they are very likely to suffer from additional health issues which often make surgery ill-advised.
However, in the case of early diagnosis, lung cancer surgery can improve prognosis substantially. The illness of up to 80% of patients suffering from stage I non-small cell lung cancer is completely cured following surgery, whereas approximately 45% of them will reach a 5-year survival.
While chemotherapy cannot cure lung cancer, it is highly effective in keeping the disease under control by reducing the size of tumor, preventing cancer from spreading, as well as destroying malignant cells which infiltrated the lymphatic system. As people who struggle with lung cancer as a consequence of asbestos exposure are very likely to experience a relapse after surgery, undergoing chemotherapy is instrumental in prolonging survival.
The chemotherapy drugs a patient will receive and the duration of treatment are determined by factors such as cell type and their overall health. Therefore, each person struggling with lung cancer will be prescribed a unique chemotherapy regimen. Nevertheless, the downside of chemotherapy is that in addition to malignant cells, medication also targets other rapidly dividing cells in the body, including red and white blood cells, hair follicles, and the cells in the lining of the stomach. For this reason, people who undergo chemotherapy will unavoidably experience a series of side effects, whose severity depends on the specific drug they are taking.
Lung cancer chemotherapy generally involves a combination of two drugs. The duration of a chemotherapy cycle is usually 3-4 weeks. Following two cycles of chemotherapy, the tumor of 70% of lung cancer patients will shrink considerably. Some of the most effective medication for non-small cell lung cancer are:
In certain cases, lung cancer patients may also receive chemotherapy prior to undergoing surgery so as to reduce the size of tumor, which is known as neoadjuvant chemotherapy. Similarly, they may be administered this treatment post-surgery in order to prevent the recurrence of cancer.
This cancer treatment employs high-energy targeted radiation to inhibit the division of malignant cells and reduce the size of tumor. As with chemotherapy, radiation therapy cannot lead to the complete remission of lung cancer. Therefore, it is primarily used as a palliative treatment. Lung cancer patients who do not qualify for surgery may be recommended a treatment regimen involving both chemotherapy and radiation therapy. Known as chemoradiation therapy, this approach is significantly more effective than chemotherapy or radiation therapy alone.
It is worthy of note that radiation therapy was found to have significantly better results in the treatment of non-small cell lung cancer. As for small cell lung cancer, it proved to be quite inefficient in preventing the spread of malignant cells.
If you believe you might be suffering from lung cancer as a consequence of asbestos exposure, seeking medical assistance as soon as possible can help improve your prognosis tremendously and may even save your life. Feel free to contact us at 760-208-4196 or by filing out the form on our Contact page and we will promptly direct you to a specialist in your area.