Second-hand smoke is the third leading cause of lung cancer and has been found to increase a person’s risk “with the extent of exposure determining the associated risk,” according to Dr. Megan Baumgart, an assistant professor in the department of medicine, hematology/oncology at the Wilmot Cancer Institute in Rochester, New York.
Each year, 7,000 adults die from second-hand smoke.10 Those who live with a smoker or who are exposed to it in the workplace are at a 20 to 30 percent increased risk of developing lung cancer.11 In fact, if lung cancer in non-smokers was considered its own category, it would rank in the top 10 deadly cancers in the U.S.12
Laws that ban public smoking have helped to reduce the danger, and organizations such as the American Cancer Society Cancer Action Network are working to strengthen such laws.
4. Environmental factors
Radon gas is the number one cause of lung cancer in non-smokers, accounting for 21,000 deaths each year.13 This odorless, tasteless gas occurs in nature and is normally harmless; however, it can become concentrated within homes that are constructed in soil with uranium deposits. The only way to determine whether it exists in high levels within a home is to test for it.
Air pollution was designated a cancer-causing agent in 2013 by the World Health Organization. In the U.S., however, the risk of developing lung cancer due to air pollution is smaller than in other countries due to environmental policies.
Other environmental factors that increase the risk for lung cancer include exposure to asbestos, arsenic, tar, soot, chromium and nickel. Inflammation, most commonly caused by foods such as white bread and sugar-laden products, has also been found to be a contributing risk factor.
5. Screening could benefit high-risk cases
Though new screening techniques are being developed that aim to diagnose lung cancer in its earlier stages, current screening won’t typically prevent lung cancer from developing unless a person is considered high risk. High-risk people, according to the U.S. Preventive Services Task Force (USPSTF), are:
- Current smokers or smokers who quit within the past 15 years
- And who are 55 to 80 years old
- And have smoked at least one pack of cigarettes each day for 30 years or two packs a day for 15 years
For these smokers or former smokers, annual screenings with a low-dose CT scan (LDCT) can prevent a significant number of “lung-cancer-related deaths.”
6. Lung cancer is treatable when caught early
Treatment for lung cancer depends on several factors such as the type of cancer, where the tumours are located, the stage of cancer, and the patient’s overall health.
When lung cancer is diagnosed in its early stages, long-term survival rates increase. But because symptoms typically do not develop until later, it is often difficult to make a correct diagnosis until the cancer is in an advanced stage. The five-year survival rate for cases in which the cancer is found early—when it is still confined to the lungs— is 52 percent.14 Once it has spread to other organs, however, the survival rate falls to just four percent.15
Early-stage non-small cell lung cancer—a form that is most commonly caused by smoking—has a better prognosis than other forms through the use of surgery or radiation therapy.
Clinical trials are ongoing throughout most of the U.S. and the National Cancer Institute encourages anyone diagnosed with lung cancer to consider participating, particularly those who have been diagnosed with non-small cell lung cancer.
7. Positive results from new medications
During the last decade, new, targeted therapies, treatments that focus on specific irregularities within the tumours themselves, have begun to show promise. Some of these include bevacizumab (Avastin), which stops tumours from forming a new blood supply; and erlotinib (Tarceva), which prevents chemicals from telling cancer cells to multiply.
Immunotherapy drugs—drugs that help the immune system reboot and fight cancer—are another new medication showing promise, and “side effects could be more favorable than chemotherapy drugs,” Dr. Eric S. Kim, an assistant professor in the department of medicine, hematology/oncology at the Wilmot Cancer Institute in Rochester, New York, said in an April 2015 interview with Live Science.