According to the American Lung Association, lung cancer is the leading cause of cancer deaths for men and women in the United States.

Doctors divide lung cancer into two main types based on the appearance of the cancer cells under a microscope. The two types are small cell lung cancer and non-small cell lung cancer, which is more common.

If you think you have symptoms of lung cancer, see your doctor immediately.

They will:

  • evaluate your medical history
  • assess your risk factors
  • perform a physical exam

If necessary, your doctor may then recommend additional testing.

Lung cancer testing can put people at unnecessary risk. Still, screenings can help detect lung cancer early on, since people don’t usually show symptoms until the disease has advanced.

Your doctor may recommend a screening test if you’re at higher risk for lung cancer. Diagnosing lung cancer early usually means you’ll have a better chance for effective treatment.

Can lung cancer be found early?

Lung cancer symptoms often don’t appear until later stages of the disease. As a result, screening is typically necessary to identify the cancer early, when it’s easier to treat.

Regular low-dose CAT (LDCT) scans may help find lung cancer in people who have a higher risk for the disease. The scans can show abnormal parts of the lungs more effectively than X-rays.

Yearly screenings are recommended for people who:

  • currently smoke, or quit smoking within the past 15 years
  • are or were a heavy smoker
  • are 55 to 80 years old

It’s important to know that LDCT screenings will not always detect lung cancer early or at all. Scans and additional tests that may go with them also have their own risks.

Talk with your doctor about the risks and benefits of lung cancer screenings.

Lung nodules

Lung nodules are small, abnormal growths in the lungs.

Most of the time, lung nodules result from scar tissue or other causes. According to the Veterans Health Administration, under 5 percent of small lung nodules are cancerous.

Still, if your doctor finds a lung nodule during a scan, they will likely want to make sure it isn’t cancer. You may start by getting another CT scan in a few months or a year to see if the nodule changes or grows.

If scans show that the nodule has grown, your doctor may order a positron emission tomography (PET) scan or perform a biopsy to check for cancer.

Signs and symptoms of lung cancer

Symptoms often don’t show up until lung cancer is advanced. Since the same symptoms may also indicate another condition, lung cancer may be difficult to detect.

Symptoms of lung cancer can include:

In later stages of lung cancer, you may have symptoms in other parts of your body, such as:

Talking with your doctor when you first start to experience symptoms may help lung cancer be diagnosed and treated earlier.

Your doctor may use a variety of tests and scans to look for the presence of lung cancer. Next, other tests like a sputum cytology or biopsy will examine your lung cells for cancer to confirm the diagnosis.

Physical exam

Your doctor will ask about your symptoms and medical history. They will check your vital signs like heart rate and blood pressure, listen to your breathing, and check for swollen lymph nodes.

They may order additional testing if they notice anything abnormal.

CT scan

A CT scan is an X-ray that takes internal pictures as it rotates around your body, providing a more detailed image of your internal organs. It may involve swallowing contrast dye or having it injected into your vein.

These scans can help your doctor identify early cancers or tumors better than standard X-rays.


Your doctor will insert a thin, lighted tube called a bronchoscope through your mouth or nose and down into your lungs to examine the bronchi and lungs. They may take a cell sample for examination.

Sputum cytology

Sputum, or phlegm, is a thick fluid you cough up from your lungs. Your doctor will send a sputum sample to a lab for microscopic examination for any cancer cells or other abnormal cells.

Lung biopsy

Imaging tests can help your doctor detect masses and tumors. Some tumors can have characteristics that are suspicious, but radiologists can’t be certain if they’re benign or malignant.

Only examining lung cells through biopsies or other tests can help your doctor verify whether suspicious lung lesions are cancerous. A biopsy will also help them determine the type of cancer and help guide treatment.

Several methods of lung biopsy include the following:

  • Thoracentesis. In this procedure, your doctor will insert a long needle between your ribs to take a sample of fluid, called pleural effusion, between the layers of tissue lining your lung. They may also perform a pleural biopsy to take a sample of the tissue itself.
  • Fine needle aspiration. Your doctor will use a thin needle to take cells from your lungs or lymph nodes.
  • Core biopsy. A core biopsy is similar to a fine needle aspiration. Your doctor will use a needle to take a larger sample called a “core.”
  • Mediastinoscopy. In a mediastinoscopy, your doctor will insert a thin, lighted tube through a small incision at the top of your breastbone to visualize and take tissue and lymph node samples.
  • Endobronchial ultrasound. Your doctor will use sound waves to guide a bronchoscope down your trachea, or “windpipe,” to look for tumors and create images of them if they’re present. They may take samples from the areas in question.
  • Thoracoscopy. Your doctor will make small incisions in your chest and back to examine lung tissue with a thin tube. This procedure can check if the cancer has spread and can also take tissue samples.
  • Thoracotomy. In a thoracotomy, your surgeon will make a long incision in your chest to remove lymph node tissue and other tissue for examination. This major procedure is often used to treat lung cancer rather than to diagnose it.

Often, doctors use a CT scan as an initial imaging test.

CT scans give your doctor a picture of your lungs and other organs where the cancer may have spread, like your liver and adrenal glands. Doctors may also use CT scans to guide biopsy needles.

Other tests may be necessary to determine if and where cancer has spread, or metastasized, in the body:

  • MRI. Your doctor may order an MRI when they suspect lung cancer may have spread to the brain or spine.
  • PET scan. This scan involves the injection of a radioactive drug, or tracer, which will collect in cancer cells and allow your doctor to see the areas with cancer. It may be combined with a CT scan for a more detailed image.
  • Bone scans. Doctors may order bone scans if they suspect cancer has spread to the bones. These involve injecting radioactive material into your vein, which builds up in abnormal or cancerous areas of the bone. They can then see the abnormal areas through imaging.

The stage of lung cancer describes the progression or extent of the cancer.

If you receive a lung cancer diagnosis, the stage will help your doctor create a treatment plan for you. Staging doesn’t solely indicate the course and outcome of your lung cancer.

Lung cancer is mainly classified as either small-cell or non-small cell lung cancer. Non-small cell lung cancer is more common, accounting for around 80 to 85 percent of lung cancers, according to the American Cancer Society.

Stages of non-small cell lung cancer

Non-small cell lung cancer may be anywhere from stage 0 to 4, with letters showing additional levels of progression. Many of the stages have different combinations of factors that may still be labeled as the same stage.

For example, lung cancer with a smaller tumor that has spread to the lymph nodes and cancer with a larger tumor that has not spread to the lymph nodes may both be stage 2B.

The following are some of the common criteria for each stage.

Occult stageLung cancer cells are in sputum or in a sample collected during a test, but no sign of a tumor in the lungs is present.
Stage 0Cancer cells are in the innermost lining of the lung only and the cancer isn’t invasive.
Stage 1AThe cancer is in the innermost lining of the lungs and deeper lung tissue. Also, the tumor is no more than 3 centimeters (cm) across and hasn’t spread to the lymph nodes or other parts of the body.
Stage 1BThe tumor is between 3 and 4 cm across and may have grown deeper into the lung tissue or through the lung and into the pleura, but it hasn’t spread to the lymph nodes. Surgery and sometimes chemotherapy are treatment options for lung cancers in stage 1A and 1B.
Stage 2AThe tumor is between 4 and 5 cm in diameter and may be partly blocking the airways, but the cancer has not spread to the lymph nodes.
Stage 2BThe tumor is between 3 and 5 cm in diameter, may have grown into the membranes covering the lungs and has spread to the lymph nodes on the same side of the chest as the tumor.
Stage 3AThe tumor is between 5 and 7 cm in diameter and may have grown into the wall of the chest. The cancer has additionally spread to the lymph nodes on the same side as the tumor. Treatment for this stage may involve a combination of surgery, chemotherapy, and radiation.
Stage 3BThe tumor may be any size, but the cancer has spread to the lymph nodes on one or both sides of the body, and possibly to the heart, major blood vessels, or esophagus. Treatment for this stage involves chemotherapy and radiation.
Stage 3CThere may be two or more individual tumors, the tumor is more than 5 cm in diameter, and the cancer has spread to the lymph nodes on one or both sides of the body.
Stage 4AThe tumor may be any size, and the cancer has spread to either the other lung or to other areas of the body, likely the adrenal glands, liver, bones, or brain.
Stage 4BThe tumor may be any size, and the cancer has spread as multiple tumors to other areas of the body. Treatment for stage 4 may involve chemotherapy, radiation, immunotherapy, and supportive, or comfort, care.

Stages of small-cell lung cancer

The same numbering system may be used for both types of lung cancer, but it mostly applies to non-small cell lung cancer. Small-cell lung cancer is usually identified by two stages, called “limited” and “extensive.”

The limited stage is confined to the chest and is usually in one lung and neighboring lymph nodes. Standard treatments include chemotherapy and radiation therapy.

Small-cell lung cancer is more likely to be diagnosed in the extensive stage. This stage involves both lungs and other parts of the body.

Doctors usually treat this stage with chemotherapy and supportive care, and may also use immunotherapy and radiation.

If you have this type of lung cancer, you may want to see if you’re a candidate for a clinical trial designed to evaluate the efficacy and safety of new drugs.

According to the National Cancer Institute, the overall 5-year survival rate for lung and bronchus cancer is 20.5 percent. For lung cancer diagnosed at an early stage, the 5-year survival rate nearly triples to 59 percent.

The survival rate doesn’t predict the outcome of your particular case. Your individual outlook depends on several factors, including:

  • the type of cancer
  • the stage of your cancer
  • your symptoms
  • your age and health
  • other health conditions
  • your response to treatment

Receiving treatment in the early stages of lung cancer can help effectively manage the disease. If you have symptoms of lung cancer, talk with your doctor.