Facts

Non-small cell lung cancer is classified into two main subtypes.

• Squamous cell carcinoma — which tends to be centrally located because it arises from the lining of your airways. Squamous cell carcinomas account for about 25 to 30 percent of all lung cancers.
• Nonsquamous non-small cell lung cancer — the most common type of lung cancer. This name covers a variety of cancers.
  • The most common is adenocarcinoma, which begins in the glands that line your airways and is often found in an outer area of the lung.
  • About 40 percent of lung cancers are adenocarcinomas. This is the most common type of lung cancer in non-smokers.

Small cell lung cancer occurs almost exclusively in heavy smokers. It usually starts in the bronchi, grows very quickly and creates large tumors. Most small cell lung cancers spread to sites outside the lung, such as the bones, liver or brain, before they are discovered.

Mesothelioma is an uncommon type of cancer related to the lungs. It arises from the pleura, the tissue that covers your lungs and lines your chest cavity, and is often linked to asbestos exposure.

• Coughing — If you develop a new cough, you have a persistent cough that lasts more than two weeks or causes pain, or you cough up blood (a serious symptom), tell your doctor.
• Chest infection — Infections, like bronchitis or pneumonia, that don’t get better or recur, may be a lung cancer symptom.
• Trouble breathing — If you experience shortness of breath or wheezing, see your doctor to find out the reason.
• Chest discomfort — This could be a symptom of several different problems, including a heart or lung condition. If it’s persistent or sudden and severe, get medical attention immediately.
• Loss of appetite — Many illnesses, including cancer, cause changes in appetite. Keep track of this symptom and report it to your doctor if it persists.
• Weight loss — If you are losing weight for no known reason, let your doctor know.
• Fatigue — Excessive tiredness or weakness is common for many illnesses, including cancer. 

• Neck and facial swelling
• Aching bones or joints or back pain
• Headaches and dizziness
• Lumps in the neck
• Pain, swelling or weakness in or around the chest or in distant parts of the body, which may indicate that cancer has spread

Conditions other than cancer may cause these symptoms. If you have any symptoms that concern you or if you are at high risk for developing lung cancer, talk to your doctor.

If you are or were a smoker and suspect you might have or might develop lung cancer, learn more about SCCA's low-dose CT screening program.

The SCCA lung cancer team has a methodical and scientific approach to lung cancer staging that allows many patients to have more aggressive therapy with a goal of curing their disease, even when this may not have seemed possible based on initial X-ray evaluations.

X-rays can be misleading, so it is important to verify any X-ray findings that suggest you have more advanced cancer. Your cancer could be less advanced and your treatment options could be different than X-rays suggest.

To determine the stage of your disease:

• You may need scans, such as a CT scan, magnetic resonance imaging (MRI) scan, positron emission tomography (PET) scan, bone scan and brain scan.
• You may have a procedure called mediastinoscopy, in which a lighted scope is inserted through an incision in your neck to look at tissues in your chest.
• Your doctor may want to do biopsies of lymph nodes or suspicious areas seen on X-rays.

Non-small cell lung cancer is assigned an overall stage of I, II, III or IV, with stage I being the least advanced and stage IV being the most advanced. The stages may be further subdivided based on more precise features of the cancer.

Small cell lung cancer stages

Small cell lung cancer is staged as limited or extensive.

• Limited stage — The cancer is on one side of your chest and involves one region of your lung, your mediastinum (area between your lungs) and lymph nodes. 
• Extensive stage — The cancer has spread outside your lungs to other parts of your body.

Cigarette smoke contains more than 7,000 chemicals, many of them cancer-causing substances (carcinogens) that damage the cells in the lungs. At first your body may be able to repair the damage caused by the carcinogens, but with repeated exposure, the damage may progress to cancer.

The risk of lung cancer increases with the length of time and number of cigarettes you’ve smoked. Lung cancer occurs most frequently among people over 50 who have smoked for many years.

Heavy smokers are at the highest risk for lung cancer, but former smokers are also at risk. Nearly 60 percent of lung cancers are diagnosed in people who have already stopped smoking.

About 18 percent of people who develop lung cancer are lifetime never-smokers. As with many cancers, the cause is unknown. Secondhand smoke is thought to be responsible for about a quarter of cases of lung cancer in never-smokers.

Other risk factors for lung cancer include:

• Exposure to environmental carcinogens, including:
  • Radon (a naturally occurring radioactive gas that results from the breakdown of uranium in soil and rocks)
  • Asbestos
  • Chemicals or minerals, such as arsenic, beryllium, cadmium, chromium, nickel or silica
  • Diesel exhaust
• Radiation exposure from occupational, medical or environmental sources
• History of lung cancer, Hodgkin or non-Hodgkin lymphoma or head or neck cancer
• History of emphysema, chronic obstructive lung disease or pulmonary fibrosis
• Family history of lung cancer

Tobacco use combined with one of these other risk factors can increase your lung cancer risk exponentially.