Lung cancer

Facts

Seattle Cancer Care Alliance (SCCA) offers comprehensive treatment from a team of experts who specialize in lung cancer.

What is lung cancer?

Lung cancer is the result of damage to normal cells in the lung. Cancer that begins somewhere else in the body may spread to the lungs; this is different from lung cancer.

  • Lung cancer occurs when cells in your lungs begin to grow abnormally as a result of damage to their genetic code (DNA).
  • Cancer cells do not behave like normal cells — they grow abnormally and do not respond to signals to stop growing.
  • Cancer cells also don’t organize normally. Instead they grow into a tumor, which may invade surrounding layers of tissue and spread to other organs.
  • The cancer cells can enter your lymph system and begin to grow in lymph nodes around your bronchi and between your lungs (mediastinum).
  • If lung cancer has reached your lymph nodes, it is more likely to have spread to other parts of your body, forming tumors (metastases) there.
Lymph system The tissues and organs that produce, store and carry white blood cells that fight infections and other diseases. The tissues and organs that produce, store and carry white blood cells that fight infections and other diseases. This system includes the bone marrow, spleen, thymus, lymph nodes and lymphatic vessels (a network of thin tubes that carry lymph and white blood cells). Lymphatic vessels branch, like blood vessels, into all the tissues of the body.
Lungs

Understanding your lungs

To understand lung cancer, it helps to know more about your lungs and lymph system.

Your lungs are sponge-like organs that work with your ribs, chest muscles and diaphragm muscle to move air in and out of your body, bringing in oxygen when you inhale and getting rid of carbon dioxide when you exhale.

  • Air travels down your trachea, through your bronchi and bronchioles, into your alveoli and back out again.
  • Your alveoli exchange carbon dioxide for oxygen through tiny blood vessels. The oxygen is carried to other parts of your body through your bloodstream.

Each lung has sections called lobes.

  • Your right lung has three lobes and is slightly larger than your left.
  • Your left lung has two lobes and is smaller because your heart takes up room on that side of your body.

Around your lungs are lymphatic vessels, small tubes that carry lymph away from your lungs.

  • Lymph is clear fluid that carries waste products and immune system cells. 
  • In certain places along the lymphatic vessels you have lymph nodes — small, oval-shaped organs of the immune system.
  • Lymphatic vessels link lymph nodes in the lungs to lymph nodes in the mediastinum.
Diaphragm The thin muscle below the lungs and heart that separates the chest from the abdomen. Lymph system The tissues and organs that produce, store and carry white blood cells that fight infections and other diseases. The tissues and organs that produce, store and carry white blood cells that fight infections and other diseases. This system includes the bone marrow, spleen, thymus, lymph nodes and lymphatic vessels (a network of thin tubes that carry lymph and white blood cells). Lymphatic vessels branch, like blood vessels, into all the tissues of the body.
What sets SCCA apart. Caring and highly skilled doctors, like Michael Mulligan, are improving lung cancer treatment so you not only survive but thrive.

Types

There are two main types of lung cancer:

  • Non-small cell lung cancer, which accounts for about 85 percent of all lung cancers
  • Small cell lung cancer, which makes up about 15 percent
Non-small cell lung cancer

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

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

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.

Symptoms

Lung cancer symptoms may take years to develop, and often there are no symptoms at all until the later stages of the disease.

The early symptoms of lung cancer are often mistaken for less serious problems. Or, in people who smoke, they are thought to be related to tobacco use alone.

Symptom A physical or mental problem that a person experiences that may indicate a disease or condition. Symptoms cannot be seen and do not show up on medical tests. A physical or mental problem that a person experiences that may indicate a disease or condition. Symptoms cannot be seen and do not show up on medical tests. Some examples of symptoms are headache, fatigue, nausea and pain.
Early signs and symptoms
  • 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. 
Pneumonia A severe inflammation of the lungs in which the alveoli (tiny air sacs) are filled with fluid. This may reduce the amount of oxygen that blood can absorb from air breathed into the lung. A severe inflammation of the lungs in which the alveoli (tiny air sacs) are filled with fluid. This may reduce the amount of oxygen that blood can absorb from air breathed into the lung. Pneumonia can be caused by infection, radiation therapy, allergy or irritation from inhaled substances. It may involve part or all of the lungs. Recur To come back. Symptom A physical or mental problem that a person experiences that may indicate a disease or condition. Symptoms cannot be seen and do not show up on medical tests. A physical or mental problem that a person experiences that may indicate a disease or condition. Symptoms cannot be seen and do not show up on medical tests. Some examples of symptoms are headache, fatigue, nausea and pain.
Late signs and symptoms
  • 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.

Computed tomography A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are used to create three-dimensional (3-D) views of tissues and organs. A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create three-dimensional (3-D) views of tissues and organs. A dye may be injected into a vein or swallowed to help the tissues and organs show up more clearly. This scan may be used to help diagnose disease, plan treatment or find out how well treatment is working. Screening Checking for disease when there are no symptoms. Because screening may find diseases at an early stage, there may be a better chance of curing the disease Checking for disease when there are no symptoms. Because screening may find diseases at an early stage, there may be a better chance of curing the disease. Examples of cancer screening tests are the mammogram (for breast cancer), colonoscopy (for colon cancer) and Pap and HPV tests (for cervical cancer). Screening can also include a genetic test to check for a person’s risk of developing an inherited disease. Symptom A physical or mental problem that a person experiences that may indicate a disease or condition. Symptoms cannot be seen and do not show up on medical tests. A physical or mental problem that a person experiences that may indicate a disease or condition. Symptoms cannot be seen and do not show up on medical tests. Some examples of symptoms are headache, fatigue, nausea and pain.

Diagnosing

SCCA’s Lung Cancer Early Detection & Prevention Clinic is your gateway to getting a diagnosis if you’re suspected of having lung cancer or to reducing your risk if you’re lung cancer–free. 

Sometimes lung cancer is detected before symptoms appear through a chest X-ray or other exam ordered for reasons not related to the cancer.

Your doctor may order imaging tests, such as an endobronchial ultrasound, a chest X-ray or a computed tomography (CT) scan to help diagnose lung cancer.

To confirm the diagnosis, you will need a biopsy. This involves taking a sample of tissue and looking at the cells under a microscope. A number of methods can be used.

  • Bronchoscopy — A thin, lighted tube (bronchoscope) is inserted through your mouth or nose, down your windpipe and into your breathing passages so doctors can see inside and take a tissue sample.
  • Endobronchial ultrasound–guided transbronchial needle aspiration (EBUS TBNA) — A special bronchoscope with an ultrasound processor is used to see the area between your lungs and take a tissue sample without any incisions.
  • Needle biopsy — A needle is inserted through your chest wall into the tumor, usually under the guidance of CT imaging, to withdraw cells. This method might also be used to withdraw cells from tumors in other areas of your body, if you have any.
  • Thoracentesis — A needle is used to remove fluid surrounding your lungs.
  • Mediastinoscopy — A thin, lighted tube (mediastinoscope) is inserted through a small incision in your neck just above or next to your breastbone to see your lungs and surrounding lymph nodes and take a tissue sample.
  • Thoracotomy — A surgeon opens your chest surgically to access the tumor.

If a biopsy confirms that cancer is present, your doctor will determine the type of cancer and the stage — how far the cancer has spread within your lungs or to other parts of your body.

SCCA’s Lung Cancer Early Detection & Prevention Clinic

Biopsy The removal of a sample of tissue or fluid that is examined to see whether cancer is present. This may be done with a large needle or through surgical removal of tissue or fluids. Chest X-ray A type of high-energy radiation that can go through the body and onto film, making pictures of areas inside the chest, which can be used to diagnose disease. An X-ray is a type of high-energy radiation that can go through the body and onto film, making pictures of areas inside the chest, which can be used to diagnose disease. Computed tomography A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are used to create three-dimensional (3-D) views of tissues and organs. A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create three-dimensional (3-D) views of tissues and organs. A dye may be injected into a vein or swallowed to help the tissues and organs show up more clearly. This scan may be used to help diagnose disease, plan treatment or find out how well treatment is working. Computed tomography A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are used to create three-dimensional (3-D) views of tissues and organs. A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create three-dimensional (3-D) views of tissues and organs. A dye may be injected into a vein or swallowed to help the tissues and organs show up more clearly. This scan may be used to help diagnose disease, plan treatment or find out how well treatment is working. Imaging In medicine, a process that makes pictures of areas inside the body. Imaging uses methods such as X-rays (high-energy radiation), ultrasound (high-energy sound waves) and radio waves. Stage The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer and whether the cancer has spread from the original site to other parts of the body. Symptom A physical or mental problem that a person experiences that may indicate a disease or condition. Symptoms cannot be seen and do not show up on medical tests. A physical or mental problem that a person experiences that may indicate a disease or condition. Symptoms cannot be seen and do not show up on medical tests. Some examples of symptoms are headache, fatigue, nausea and pain. Ultrasound A procedure that uses high-energy sound waves to look at tissues and organs inside the body. The sound waves make echoes that form pictures of the tissues and organs on a computer screen. A procedure that uses high-energy sound waves to look at tissues and organs inside the body. The sound waves make echoes that form pictures of the tissues and organs on a computer screen (sonogram). Ultrasound may be used to help diagnose diseases, such as cancer. It may also be used during pregnancy to check the fetus (unborn baby) and during medical procedures, such as biopsies. Also called ultrasonography.

Stages

Accurate staging is probably the most important part of lung cancer treatment because it helps your doctors choose the most appropriate therapy for you (and can help you avoid ineffective therapy).

Staging Performing exams and tests to learn the extent of the cancer within the body, especially whether the disease has spread from where it first formed to other parts of the body. Performing exams and tests to learn the extent of the cancer within the body, especially whether the disease has spread from where it first formed to other parts of the body. It is important to know the stage of the disease in order to plan the best treatment.
How we determine the stage

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.
Biopsy The removal of a sample of tissue or fluid that is examined to see whether cancer is present. This may be done with a large needle or through surgical removal of tissue or fluids. Bone scan A procedure to check for abnormal areas or damage in the bones. A bone scan may be used to diagnose bone tumors or cancer that has spread to the bone. A procedure to check for abnormal areas or damage in the bones. A very small amount of radioactive material is injected into a vein and travels through the blood. The radioactive material collects in the bones and is detected by a scanner (a special camera that takes pictures of the inside of the body). A bone scan may be used to diagnose bone tumors or cancer that has spread to the bone. It may also be used to help diagnose fractures, bone infections or other bone problems. [removed comma] Computed tomography A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are used to create three-dimensional (3-D) views of tissues and organs. A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create three-dimensional (3-D) views of tissues and organs. A dye may be injected into a vein or swallowed to help the tissues and organs show up more clearly. This scan may be used to help diagnose disease, plan treatment or find out how well treatment is working. Imaging In medicine, a process that makes pictures of areas inside the body. Imaging uses methods such as X-rays (high-energy radiation), ultrasound (high-energy sound waves) and radio waves. Stage The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer and whether the cancer has spread from the original site to other parts of the body. Staging Performing exams and tests to learn the extent of the cancer within the body, especially whether the disease has spread from where it first formed to other parts of the body. Performing exams and tests to learn the extent of the cancer within the body, especially whether the disease has spread from where it first formed to other parts of the body. It is important to know the stage of the disease in order to plan the best treatment.
Non-small cell lung cancer stages

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.
Stage The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer and whether the cancer has spread from the original site to other parts of the body.

What causes lung cancer?

More than 85 percent of lung cancers are related to tobacco, either by smoking or breathing secondhand smoke, and about half of all continuing smokers will die from a disease caused by smoking.

Get help to quit smoking, and learn about early detection at SCCA, including lung cancer screening for smokers and ex-smokers.

Screening Checking for disease when there are no symptoms. Because screening may find diseases at an early stage, there may be a better chance of curing the disease Checking for disease when there are no symptoms. Because screening may find diseases at an early stage, there may be a better chance of curing the disease. Examples of cancer screening tests are the mammogram (for breast cancer), colonoscopy (for colon cancer) and Pap and HPV tests (for cervical cancer). Screening can also include a genetic test to check for a person’s risk of developing an inherited disease.
Lung cancer due to smoking

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 lung cancer risk factors

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.

Lymphoma Cancer that begins in the cells of the immune system. There are two basic categories of lymphomas: Hodgkin lymphoma and non-Hodgkin lymphomas. Cancer that begins in cells of the immune system. There are two basic categories of lymphomas. One is Hodgkin lymphoma, which is marked by the presence of a type of cell called the Reed-Sternberg cell. The other category is non-Hodgkin lymphomas, which includes a large, diverse group of cancers of immune system cells. Non-Hodgkin lymphomas can be further divided into cancers that have an indolent (slow-growing) course and those that have an aggressive (fast-growing) course. These subtypes behave and respond to treatment differently. Both Hodgkin and non-Hodgkin lymphomas can occur in children and adults, and prognosis and treatment depend on the stage and the type of cancer.

How common is lung cancer?

Lung cancer is the most common cancer after skin cancer, and it is the leading cause of cancer death for both men and women in the United States. Each year, more Americans die of lung cancer than of breast, colorectal, ovarian and prostate cancers combined.

About 222,000 new lung cancer cases are diagnosed in the U.S. each year.