Screening and Diagnosis

Lung Cancer Screening Program

The Northwestern Medicine Lung Cancer Screening Program specializes in the imaging evaluation of patients at a high risk for lung cancer. Our mission is to provide evidence-based, timely and personalized care for patients who undergo lung cancer screening.

Learn more about the program.

Lung Cancer Risk Factors

Lung cancer risk factors are anything that increases your chance of developing the disease. There are lung cancer risk factors you can control and some that you can’t.

Lung Cancer Risk Factors You Can Control

  • Smoking tobacco. According to the American Cancer Society (ACS), roughly 80% of lung cancer deaths result from smoking. Your risk for developing lung cancer increases the longer that you smoke and the more you smoke. This includes smoking pipes, cigars and menthol cigarettes.
  • Exposure to secondhand tobacco smoke. According to ACS, secondhand smoke causes roughly 7,000 lung cancer deaths annually.
  • Exposure to other chemicals and substances. This includes:
    • Radon
    • Asbestos
    • Workplace exposure to cancer-causing agents like uranium, arsenic, and coal products such as diesel exhaust

Lung Cancer Risk Factors You Can’t Control

  • Radiation therapy. If you had radiation therapy for other chest cancers, such as breast cancer, your risk of developing lung cancer increases.
  • Air pollution exposure. It is estimated that roughly 5% of lung cancer deaths worldwide are due to air pollution.
  • Personal or family history. If you had lung cancer, your chance of developing it again increases. If you have a sibling or parent who was diagnosed with lung cancer, especially at a young age, your risk increases as well.

Reducing your risk of lung cancer starts by reducing the risk factors you can control — most importantly quitting smoking.

Diagnosing Lung Cancer

Your care team will use a variety of leading-edge methods to diagnose lung cancer.

Tests and imaging to diagnosis your lung cancer may include:

  • The Northwestern Medicine Ambulatory Precision Lung Sparing (A-PLUS) Surgery Program: This advanced technology can diagnose and treat early-stage lung cancer in a minimally invasive outpatient procedure.
  • Computed tomography (CT) scan: This diagnostic imaging procedure uses X-rays and computer technology to produce images of your body. CT scans are more detailed than general X-rays.
  • Interventional Pulmonology: Delivering care with leading-edge technologies with a focus on the evaluation of possible lung cancer and informed by the latest research in collaboration with Northwestern University Feinberg School of Medicine.
  • Magnetic resonance imaging (MRI): Using large magnets, radiofrequencies and a computer, an MRI produces detailed images of organs and structures in your body.
  • Molecular Testing: Identifies patients with advanced non-small cell lung cancer (NSCLC) who may benefit from targeted therapy or immunotherapy.
  • Positron emission tomography (PET): For this test, a radioactive substance, usually chemically bound to a type of sugar, is injected through a vein before your body is scanned. The radioactive sugar collects in cancer cells, which will show up on images. A PET is sometimes done along with a CT scan.

Stages of Lung Cancer

“Staging” is the term oncologists (physicians specially trained in cancer care) use to define where lung cancer is located and how much it has spread. After the stage of lung cancer is determined, your physician can recommend a particular course of treatment.

Most cancer care teams use the system developed by the American Joint Committee on Cancer, known as the TNM staging system.

T = Tumor
Where is the primary tumor and how large is it?

N = Nodes
Has the tumor spread to nearby lymph nodes (part of your immune system)?

M = Metastasis
Has cancer spread to other parts of the body?

For each letter, there are five numbered stages, from zero to four, depending on how much the cancer has spread. The lower the number, the more the cancer cells look like normal cells and the easier they are to treat and cure. A higher number means it has spread more.

The place where cancer forms is called the primary site. Cancer can spread from the primary site to other parts of the body. Even if lung cancer is found in other parts of your body, it’s still considered lung cancer. For example, if lung cancer has spread to the brain, it’s called metastatic lung cancer, not brain cancer.

For treatment, physicians often use a simpler system of categorizing lung cancer:

  • Resectable cancer: These cancers can be surgically removed (resected).
  • Borderline resectable cancer: These cancers can be surgically removed but are very close to major blood vessels, or other important parts of your body.
  • Locally advanced cancer: These cancers are still only in the area around the lungs, but they cannot be removed completely with surgery, often because they are growing into nearby blood vessels. This category is also called unresectable because the cancer cannot be removed with surgery.
  • Metastatic cancer: These cancers have spread to other parts of the body, so they cannot be removed completely with surgery (meaning they are also unresectable). Surgery may still be done, but it's used to relieve symptoms that the tumors in other areas of the body are causing.

Talk to your physician about your stage of cancer and how that will impact your treatment.

For more information about the stages of lung cancer, please visit our Health Library.