What You Need to Know About Asbestos and Lung Cancer

Asbestos¹ has been used commercially since the 1800s, primarily for strengthening cement and plastics, for insulation and fireproofing, and for sound absorption.

Asbestos refers to a group of six minerals that occur naturally as bundles of fibers that can be separated into thin, durable threads.

The late 1970s saw the first ban on asbestos in the US, then in 1989, new uses of asbestos were also banned.

Why is asbestos a health hazard?

Asbestos structure means that it breaks off into thin fibers that you can unknowingly inhale. We can all be exposed to small amounts of asbestos that occur naturally in the environment, but some people are more at risk of heavier asbestos exposure due to the industry they work in.

When you inhale asbestos fibers, they become lodged in your lung tissue. This can cause one (or more) of these diseases:

• Asbestosis – An inflammatory condition of the lungs which causes slow, progressive scarring of the lung that results in shortness of breath, coughing, and permanent damage. It can also increase the risk of other lung conditions.

• Lung cancer – Asbestos is a known cause of lung cancer.

• Pleural mesothelioma – Cancer of the lining of the lungs. Asbestos exposure is the most common cause of this.

• Benign pleural disease – Fluid accumulation in the lungs due to fibers and plaque build-up.

About 20% of people exposed to asbestos develop some sort of lung disease as a result.

Who is most at risk from asbestos exposure?

Asbestos in buildings is not a health hazard until it is disturbed, so you don't need to worry about asbestos in your home or insulation unless you are doing renovations. Asbestos exposure risk is generally occupational, so people who are most at risk include:

• Shipbuilders

• Miners

• People involved in manufacturing asbestos products

• Insulation work in construction and building trades

• Demolition workers and drywall removers

• Firefighters

• Automobile workers

• Military personnel

• Asbestos removal workers

• Family members of people in these industries

As asbestos-related disease does not show symptoms until a long time after exposure (mesothelioma can occur 15 to 30 years post-exposure), people who worked in these industries many years ago may still be at risk.

In recent years, improved safety practices have reduced asbestos exposure, including by wearing appropriate safety gear and following decontamination procedures. The higher your amount of exposure, the higher your risk of developing lung disease. 

How common is asbestos-related lung cancer?

Asbestos-related lung cancer is rare, but it is responsible for 37.5% of occupational lung cancer cases². Smoking poses a much higher risk than asbestos exposure in terms of developing lung cancer and pleural mesothelioma. However, in combination with asbestos exposure, the risk increases to 60 times that of people who have never smoked or been exposed to asbestos.

Lung cancer is the leading cause of cancer death in the US, and lung cancer caused by asbestos kills about 6,000 people in the US each year on average. Patients with asbestos-related lung cancer who also smoke are 16 times more likely to die from their disease.

Pleural mesothelioma is much rarer, with about 2,800 cases diagnosed in the US each year, compared to about 222,500 lung cancer cases.

While asbestos exposure is the most common cause, responsible for more than 80% of mesothelioma cases, genetic factors, such as a gene mutation called BAP1 have been found in 60% of mesothelioma cases. This can be tested after you have been exposed to asbestos to determine your future cancer risk.

Asbestos causes two types of cancer:

• Small cell

• Non-small cell cancer

The type of cancer you have is important for deciding which treatment is right for you.

When does lung cancer develop after asbestos exposure?

Asbestos-related lung disease can develop even decades after the initial exposure to asbestos. Mesothelioma and asbestos-related lung cancer can develop as many as 50 years after exposure. Asbestosis can occur around 20-30 years post-exposure.

Once cancer has started to develop, it takes only months to metastasize, which contributes to the high fatality rate. The one-year survival rates are 42% for lung cancer and 39% for mesothelioma patients, with lung cancer patients having the advantage in the long term.

Early detection is absolutely vital, but this is complicated by the fact that lung cancer, in general, does not show symptoms in the early stages. If you have a history of asbestos exposure, it’s important to attend regular doctor visits to monitor for symptoms of asbestos-related lung disease and lung cancer.

Warning signs of lung cancer

The warning signs of lung cancer are the same regardless of the cause. However, many symptoms only appear in late-stage lung cancer. General symptoms to watch for are:

• Shortness of breath

• Persistent coughing

• Coughing up blood

• Fatigue

• Loss of appetite and unexplained weight loss

• Discomfort or pain in the chest

• Swelling of the face or neck

• Hoarseness

• Wheezing

• Respiratory infections that don't heal or keep returning

Signs of mesothelioma³ can come on gradually and include:

• Shortness of breath

• Discomfort or pain in the chest

• Persistent coughing

• Hoarseness

• Fever or night sweats

• Pain on swallowing

• Loss of appetite

There is overlap between the symptoms of lung cancer and mesothelioma, but they are not the same. Pleural mesothelioma, for example, does not typically cause coughing up blood, as the cancer is not in the lung cells themselves.

What should I do if I have been exposed to asbestos?

If you have had any previous asbestos exposure and you start developing symptoms, contact your doctor immediately. Asbestosis has a typical pattern of scarring that shows up on CT imaging.

If there is a lung lesion that is thought to be potentially cancerous, this may warrant a biopsy to confirm a diagnosis. A less invasive test called a bronchoscopy, where fluid is rinsed out of your lungs and checked for fibers may be a better option, but it is less reliable.

If your doctor suspects you have asbestos-related lung disease, there is some evidence that a three-to-five-yearly lung function test and CT imaging can help to detect any progression. This can help to identify the early development of lung cancer or mesothelioma. 

Lung cancer treatment

If you are diagnosed with lung cancer, there are a variety of options for treatment, depending on the stage and type of cancer. Treatment options include:

• Surgery – This only works if the cancer is diagnosed before it spreads beyond the lungs. This might involve removing a small part of the lung or even the entire lung.

• Chemotherapy.

• Radiation therapy.

• Immunotherapy – There have been a few immunotherapies (including pembrolizumab and nivolumab) approved to treat advanced non-small cell lung cancer. There are currently no therapies approved for small cell lung cancer.

• Photodynamic therapy⁴ – This is also sometimes used to treat non-small cell lung cancer.

Any of these treatments may be combined to maximize effectiveness, and there are also experiments with targeted drug therapy. For patients who are diagnosed with advanced lung cancer, it may be worth looking into clinical trials to receive further treatment and assist with the development of new treatments.

We can help you find and apply for the right clinical trial. Learn how.

How is mesothelioma treated?

If you have been diagnosed with mesothelioma, you may undergo similar treatment as with lung cancer. A difference is that surgical treatment for mesothelioma⁵ generally involves removing the lining of the lung rather than a portion or lobe. However, the entire lung may still need to be removed.

Mesothelioma is particularly difficult to treat, as it is not composed of one definitive mass like other forms of cancer. As it involves the lining of the organs, it may require radiotherapy or chemotherapy. Sometimes, it even causes fluid build-up around the lung which may require a procedure (thoracocentesis) where a tube is inserted to drain it.

Targeted therapy is also being developed for mesothelioma, but it has not yet been approved.

The prognosis for mesothelioma is generally poor as it is hard to remove all of cancer. Overall, patients typically survive for around nine to 17 months after the initial diagnosis, depending on how much cancer has spread.

The lowdown

If you have a work history that may have involved you being exposed to asbestos, it is very important to talk to your doctor and have regular evaluations to monitor for any symptoms of asbestos-related lung disease.

Asbestos-related lung cancer has a lower than average survival rate compared to other types of lung cancer, but this is primarily because it tends to only be diagnosed at a later stage.

Early diagnostic screening can save your life, as can quitting smoking which increases the risk. While not everyone who has been exposed to asbestos will develop lung cancer, being aware of your exposure is the first step to an early diagnosis and treatment.