Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. It accounts for about 80 to 85 percent of all lung cancer cases. Lung cancer occurs when tumors form in your lungs.

Though more common, NSCLC is typically less aggressive than small cell lung cancer (SCLC). Still, some forms of NSCLC can spread quickly to other parts of your body if untreated. Early diagnosis is key to improving your outlook.

An X-ray is normally the first test when doctors suspect NSCLC. X-rays can find tumors and determine their size, location, and other important characteristics.

While you’ll need a range of other tests to confirm and stage NSCLC, there’s still a lot of information your doctor can learn from an X-ray.

A chest X-ray can’t diagnose NSCLC. However, it can provide important information that your doctor can use to determine whether you need more tests.

A chest X-ray can show where in your lungs the tumor is growing. It can also help determine the type of NSCLC. Common types of NSCLC include:

Several features of NSCLC also show up on a chest X-ray. These include:

  • Bronchial stenosis. Bronchial stenosis is a narrowing of the airways (bronchial tubes) that connect your lungs to your trachea. NSCLC tumor growth can sometimes cause bronchial stenosis. This is often an indicator of squamous cell carcinoma.
  • Decreased lung density. Decreased lung density can be a sign of lung cancer. But it can also be a sign of conditions such as pneumonia and respiratory distress.
  • Hilar mass. A hilar mass is a growth at the entrance to the lungs. It often indicates lung cancer but can be benign in some cases. When hilar masses are cancerous, they can make surgery more complex.
  • Solitary pulmonary nodule (SPN). An SPN appears as a round or oval spot on a chest X-ray. They’re often noncancerous but can also be an early sign of lung cancer.
  • Pleural effusion. Pleural effusion is a buildup of fluid in the space between the lungs. Pleural effusion may be due to inflammation, trauma, or other respiratory conditions. But when pleural effusion is present along with a lung tumor, it indicates that cancer cells have moved into the space between the lungs.
  • Non-resolving pneumonia. Non-resolving pneumonia is sometimes one of the first symptoms of lung cancer. This is common in a group of adenocarcinomas previously called bronchoalveolar carcinoma.
  • Metastasis. If cancer has metastasized, it has spread to other parts of the body. X-rays can show if tumors have spread to nearby structures like your lymph nodes. This can affect your outlook and surgical options.

While chest X-rays can provide useful information, they are also limited in several ways. A 2019 review found that chest X-rays miss 2 out of every 10 lung cancer cases. Reasons for this may include:

  • Image quality. Black and white X-ray images don’t have a very high resolution. It can sometimes be difficult for even a trained radiologist to detect subtle details.
  • Obstruction. Doctors can easily miss smaller tumors if bones or other body parts block them from view. A 2017 study suggested that chest X-rays miss 45 to 81 percent of cancers in the upper lobes of the lung, where the collarbone might block them.
  • Positioning. A lot depends on whether the X-ray technician positions you properly so that they can obtain the best quality image.

Other conditions may look similar to cancer on an X-ray. For example, a lung abscess may also appear as a light gray mass on an X-ray image.

If a chest X-ray detects cancer, staging is an important part of the diagnostic process. Staging is an indication of how much the cancer has spread. The stage of the cancer has an impact on your treatment and outlook.

Chest X-rays don’t provide enough information to stage your cancer. That part of the process comes later and usually involves CT, PET, or MRI scans.

A chest X-ray is an outpatient procedure. You won’t need to stop taking any medications before the procedure, and you’ll be able to drive yourself to and from your appointment.

Before your X-ray, you’ll need to undress from the waist up. You’ll receive an exam gown to wear. You’ll also need to remove any jewelry.

You’ll stand between the X-ray machine and the plate that creates the images during your X-ray procedure. The X-ray technician will ask you to move into different positions throughout the procedure so the machine can capture different views of your chest.

The technician will help you get into different positions so the machine can capture images of the sides and front of your chest. They might also ask you to make slight movements, such as raising your arms, rolling your shoulders, or taking a deep breath and holding it.

X-rays are normally quick and painless. You won’t feel the X-ray machine taking images.

If you’re unable to stand or complete the movements, you may be able to sit or lie flat. If you’re concerned about standing during the X-ray, talk with your doctor ahead of time. They might be able to direct you to a facility that has mobility accommodations in place.

Your doctor will contact you once the results of your chest X-ray are ready. They’ll let you know the results and discuss the next steps. This might involve scheduling more tests or waiting for the results of other tests you’ve already had.

Chest X-rays are safe. The process will expose you to a small amount of radiation, but it is not enough to affect your health. However, if you have regular chest X-rays, you can wear a protective apron during the procedure to protect yourself from radiation.

If you’re pregnant, it is important to let your doctor and the X-ray technician know. You can still have a chest X-ray, but the technician will take steps to ensure your stomach isn’t exposed to radiation.

An X-ray alone isn’t enough to diagnose non-small cell lung cancer. In addition to reviewing your complete medical history and smoking habits, you’ll have a range of other tests to confirm the diagnosis.

Common tests to diagnose lung cancer include:

  • CT scan. A CT scan produces detailed 3-dimensional images that allow doctors to look closely at tumors. Sometimes, a dye, given by injection or orally, can highlight tumors and other abnormalities.
  • PET scan. Doctors may request a PET scan at the same time as a CT scan. Before a PET scan, you’ll have an injection of a form of sugar that is mildly radioactive, and that will collect in cancer cells. This can help highlight areas cancer might have spread.
  • MRI. An MRI uses magnetic fields to produce detailed images of the inside of your body. Doctors often use it to see if lung cancer has spread into your bones.
  • Sputum cytology. Sputum cytology examines the mucus you cough up. You’ll collect samples three mornings in a row and submit them to a lab for testing.
  • Biopsy. A biopsy removes a small amount of tissue for examination under a microscope. This can help determine the subtype of NSCLC. Biopsies could be a surgical procedure, or they may involve a specialized needle to remove a sample of the tumor.
  • Bronchoscopy. Bronchoscopy uses a long, thin, tube inserted down your airway and into your lungs. A light on the end of the tube allows doctors to see inside your lungs. They can also collect samples of fluids and tissues for testing.
  • Thoracentesis. Thoracentesis is a procedure that collects fluid from the space in between the lungs. It uses a long needle inserted into the wall of your chest. The fluid is then analyzed and checked for cancer cells in a lab.

A chest X-ray is an important part of the lung cancer diagnostic process. An X-ray can’t confirm a diagnosis on its own, but it can provide useful information about NSCLC type, stage, outlook, and more. It can show the location and size of a tumor.

A chest X-ray can help your doctor start to think about surgical options and other treatment strategies. You’ll need other tests to confirm findings, but a chest X-ray is often the first step.

Early diagnosis is the key to improving your outlook with NSCLC. The 5-year survival rate for localized NSCLC is 8 times higher than it is if your cancer has spread.

If you’re at high risk for NSCLC, talk with your doctor about yearly screening with a chest X-ray and low dose CT scan.