Despite reduction in numbers in recent years, lung cancer is the leading cause of cancer deaths in the United States.

Each year, an average of 218,500 people are diagnosed with lung cancer, and about 142,000 people die from the disease, according to the Centers for Disease Control and Prevention.

Though different people have different symptoms for lung cancer, most people with lung cancer don't have symptoms until the cancer is advanced, according to the CDC.

Observed annually in November, Lung Cancer Awareness Month draws attention to the disease to increase awareness of causes and symptoms of lung cancer and steps to take if you think you need to be screened.

The three leading causes of lung cancer are cigarette smoking, exposure to second-hand smoke, and exposure to radon, according to the National Institutes of Health, with 90 % of lung cancer deaths caused by smoking and the use of tobacco products.

Along with the above leading causes, previous exposure to any kind of radiation, exposure to asbestos, and family history should all be taken seriously.

Smoking, along with exposure to other causes, increases the risk of lung cancer, according to U.S. Army Major (Dr.) Mateo Houle, a pulmonologist at the Brooke Army Medical Center in Fort Sam Houston, Texas.

Despite this, lung cancer is often preventable because it is often related to behavioral choices. "Smoking is the single greatest risk factor to develop lung cancer," said Houle. "It is possible to develop lung cancer from exposure to radon or other environmental factors, but these are far less common."

Some warfighters work in locations where there may be hazardous chemicals that can possibly cause cancer. If you have concerns, Houle said, the first step should be consulting a supervisor. If there is a question, all work locations should have Material Safety Data Sheets that can be consulted.

"The MSDS is a manual that shows all the chemicals used in the workplace and their known effects following exposure. The Occupational Safety and Health Administration regulates workplace exposures/chemicals and safety," Houle said.

Unlike some cancers, most symptoms of lung cancer are not discovered until the cancer is advanced. "Unfortunately, there are no signs of lung cancer in the early stages," said Houle.

Despite there being no obvious early signs, there are symptoms one can watch for according to the NIH.

Possible Signs of Lung Cancer

• A new cough that won't go away
• Shortness of breath
• Chest pain
• Hoarseness
• Losing weight (without trying)
• Coughing up blood

Screening for Lung Cancer

"There may be appropriate screenings available to catch cancer at an early, curative stage," said Houle. Lung cancer screening is recommended only for adults who have no symptoms but who are at high risk for developing the disease because of their smoking history and age.

"We have a lung cancer screening program, and at BAMC we have a specific lung cancer screening clinic where we offer education and same day CT lung cancer screening for those who are referred here," said Houle. "We then evaluate each case of new diagnosis of lung cancer in a multidisciplinary team, once per week. We also have a smoking cessation program at BAMC which has nursing and behavioral health embedded in the clinic."

Even though lung cancer can be hard to cure, early detection can lower the risk of dying from this disease. TRICARE will cover an annual low-dose computed tomography screenings for lung cancer if the beneficiary is between 50- to 80-years-old and has a 20-pack per-year history of smoking, is currently smoking or has quit within the past 15 years.

Lung cancer screening is not without risks. That is why lung cancer screening is recommended only for adults who are at high risk for developing the disease because of their smoking history and age.

Lung Cancer Prevention

Unfortunately, there is nothing that can be done to prevent lung cancer, but there are steps you can take to minimize your risk.

• Stop smoking, or don't start.
• Avoid secondhand smoke, and don't smoke around others.
• Test your home for radon and asbestos (if appropriate).
• Take safety precautions at work if you're around toxic chemicals or carcinogens.
• Examine your diet and exercise.