• Doctors evaluate the size, location, and spread of tumors to determine what stage the cancer is.
  • Lung cancer is identified by numbered stages 0 through 4, as it progresses, with subcategories within each stage.
  • The treatment for lung cancer depends on the stage.

After you receive a lung cancer diagnosis, your doctor will want to find out where the cancer is in your body. This process is called staging.

Learning whether and where your cancer has spread can help your doctor find the right treatment for you. Your stage also helps provide an outlook.

Your doctor will assign your lung cancer a clinical stage based on the results of:

  • your physical exam
  • your biopsy
  • imaging tests such as a computed tomography (CT) scan and magnetic resonance imaging (MRI)

If you have surgery, your doctor will also give your cancer a pathological or surgical stage. The doctor finds this stage by examining the tissue removed during the biopsy.

Lung cancers are divided into two main types: small cell lung cancers and non-small cell lung cancers (NSCLC). As many as 85 percent of lung cancer cases are NCSLC.

The five general stages for lung cancer are numbered from 0 to 4.

  • Stage 0 indicates a small tumor that hasn’t spread into deeper lung tissues. Doctors also call this carcinoma in situ (CIS).
  • Stage 1 lung cancer is limited to the lungs and hasn’t spread to the lymph nodes.
  • Stage 2 lung cancer may have spread to the nearby lymph nodes.
  • Stage 3 lung cancer has spread further into the lymph nodes and the middle of the chest.
  • Stage 4 cancer has spread to both lungs, the fluid around the lungs, or to another part of the body.

Lung cancer can also be detected in samples before it presents as a tumor. This is known as an “occult” or “hidden” cancer.

Each general stage also gets a number and letter (A or B). Cancer with a lower number or the letter A has spread less than cancer with a higher number or the letter B.

Doctors stage lung cancer with a grouping system called TNM, which is based on:

  • Tumor (T): How big the main tumor in the lung is and whether it has grown into any nearby structures or organs.
  • Node (N): Whether the cancer has spread to nearby lymph nodes.
  • Metastasis (M): Whether the cancer has spread (metastasized) to distant sites like the liver or brain.

The numbers after each of these letters also show how far your cancer has spread. The higher the number, the more it has spread.

Together, the stage and stage grouping tell your doctor where your cancer is in your body. People who have the same stage and stage grouping will usually get the same treatments. This staging is typically used for NSCLC.

General lung cancer stages

StageStage groupingStage description
0Tis

N0

M0
Cancer cells are only in the inner lining of your lungs. The cancer hasn’t spread to any lymph nodes or to other parts of your body.
1A1T1 mi

N0

M0
The cancer is called a minimally invasive adenocarcinoma. It has not spread to the lymph nodes or to other parts of your body.
Or:

T1a

N0

M0
The tumor is no bigger than 1 centimeter (cm) across at its widest point. It hasn’t reached the membrane around your lungs or the main airways (bronchi). It hasn’t spread to your lymph nodes or to other parts of your body.
1A2T1b

N0

M0
The tumor is between 1 and 2 cm across. It hasn’t reached the membrane around your lungs or the airway. It hasn’t spread to lymph nodes or to other parts of your body.
1A3T1c

N0

M0
The tumor is between 3 and 4 cm across. It hasn’t reached the membrane around the lungs or the airway. It hasn’t spread to your lymph nodes or to other parts of your body.
1BT2a

N0

M0
The tumor is between 3 and 4 cm across. It may have grown into the membrane around your lungs or to the main airway. It hasn’t spread to lymph nodes or to other parts of your body.
2AT2b

N0

M0
The tumor is between 4 and 5 cm across. It may have grown into the membrane around the lungs or the airway. It hasn’t spread to lymph nodes or other parts of your body.
2BT1a/T1b/T1c

N1

M0

The tumor is less than 3 cm across. It hasn’t grown into the membrane around the lungs or the airway. It has spread to lymph nodes on the same side of the lung. It hasn’t spread to other parts of your body.
Or:

T2a/T2b

N1

M0
The tumor may be between 3 and 5 cm across. It may have grown into the airway or the membrane around the lungs. The cancer has spread to lymph nodes on the same side of your lung. It hasn’t spread to other parts of your body.
Or:

T3

N0

M0
The cancer is between 5 and 7 cm across. It may have grown into the chest wall, the outer lining of the chest cavity (parietal pleura), the nerve close to the lung (phrenic nerve), or the outer covering of the heart (pericardium). There may be two separate tumors in the same part of the lung. The cancer hasn’t spread to lymph nodes or to other parts of your body.
3AT2a/T2b

N2

M0
The tumor may be between 3 and 5 cm across. It may have grown into the airway or the membrane around the lungs. The cancer has spread to lymph nodes in the middle of the chest on the same side of the lung, or just below where the windpipe connects to each lung. The cancer hasn’t spread to other parts of your body.
Or:

T3

N1

M0
The cancer is between 5 and 7 cm across. It may have grown into the chest wall, the outer lining of the chest cavity, the nerve close to the lung, or the outer covering of the heart. There may be two or more separate tumors in the same part of a lung. The cancer has spread to lymph nodes on the same side of the lung. It has not spread to other parts of your body.
Or:

T4

N0 or N1

M0
The cancer may be bigger than 7 cm across. It may have grown into the space between the lungs (mediastinum), heart, windpipe, esophagus, diaphragm, or backbone. There may be two or more separate tumors in different parts of the same lung. The cancer may have spread to lymph nodes in the lung, but it has not spread to other parts of your body.
3BT2a/T2b

N3

M0
The tumor is 3 to 5 cm across. It may have grown into a main airway or the membranes around the lungs. It has spread to lymph nodes near your collarbone, on the other side of your chest, or at the top of the lung. It has not spread to other parts of your body.
Or:

T3

N2

M0
The tumor is 5 to 7 cm across. It may have grown into the chest wall, the outer lining of the chest cavity, the nerve close to the lung, or the outer covering of the heart. There may be two separate tumors in the same part of a lung. The cancer has spread to lymph nodes in the space between the lungs, or under the spot where the windpipe branches off to each lung. It hasn’t spread to other parts of your body.
Or:

T4

N2

M0
The tumor may be larger than 7 cm across. It may be in more than one lobe of the lung. Or it may have spread into the space between the lungs, heart, windpipe, esophagus, diaphragm, or backbone. There may be two or more separate tumors in different parts of the same lung. The cancer has spread to lymph nodes in the space between the lungs, or under the spot where the windpipe branches off to each lung. It hasn’t spread to other parts of your body.
3CT3

N3

M0
The tumor is between 5 and 7 cm across. It may have grown into the chest wall, the outer lining of the chest cavity, the nerve close to the lung, or the outer covering of the heart. It has spread to lymph nodes near the collarbone, on the other side of the chest, or at the top of the lung. The cancer hasn’t spread to other parts of your body.
Or:

T4

N3

M0
The tumor may be larger than 7 cm across. It may be in more than one lobe of the lung. Or it may have spread into the space between the lungs, heart, windpipe, esophagus, diaphragm, or backbone. There may be two or more separate tumors in different parts of the same lung. The cancer has spread to lymph nodes near the collarbone, on the other side of the chest, or at the top of the lung. It hasn’t spread to other parts of your body.
4AAny T

Any N

M1a
The cancer can be any size. It may have grown into nearby structures or to nearby lymph nodes. Cancer may have spread to the other lung. There may be cancer cells in the fluid around the lung or heart.
Or:

Any T

Any N

M1b
The cancer can be any size. It may have grown into nearby structures or lymph nodes. There is a single area of cancer in a distant lymph node or an organ such as the liver, bones, or brain.
4BAny T

Any N

M1c
The cancer may have grown into nearby structures or to nearby lymph nodes. There is more than one area of cancer in a distant lymph node or an organ such as the liver, bones, or brain.

Small cell lung cancer stages

Small cell lung cancer is diagnosed as either limited stage or extensive stage. Your doctor might also use the TNM staging system.

Limited stage lung cancer has only reached one part of the chest.

Extensive stage lung cancer may have metastasized to the lymph nodes or other parts of the body.

Lung cancer is curable if you catch it early. The cure rates for stage 0 and stage 1 lung cancers are 80 to 90 percent. People often receive a diagnosis when their lung cancer is in a later stage.

Once the cancer has spread, it is harder to cure. Treatments can slow but not stop it. Immunotherapy has been shown to extend survival in people with NSCLC over people receiving standard courses of chemotherapy.

New treatments are improving the outlook for people with lung cancer. You may be able to try one of these treatments by enrolling in a clinical trial.

The treatment for lung cancer depends on the stage.

Stage 0 lung cancer is usually curable with surgery to remove part of the lobe of one lung. This surgery is called wedge resection or segmentectomy.

Stage 1 lung cancer is also curable with surgery to remove part of a lobe (lobectomy) or a whole lobe of the affected lung. You might get chemotherapy or radiation after surgery to prevent the cancer from coming back.

Stage 2 lung cancer treatment also involves surgery to remove a lobe or the whole lung. Any lymph nodes that might have cancer in them are also removed. You may get chemotherapy or radiation after surgery to remove any cancer cells left behind after surgery.

Stage 3 may involve surgery if your doctor thinks your cancer can be removed. This is usually in combination with chemotherapy, radiation, immunotherapy, or multiple of these treatments.

Stage 4 lung cancer has already spread by the time it’s diagnosed. Surgery to remove the tumor that has spread may be part of your treatment. You’ll also likely get body-wide treatments, such as chemotherapy, immunotherapy, or targeted therapy.

The staging system shows how large a lung cancer is and where in your body it has spread. Knowing your cancer stage can help your doctor find the right treatment, and inform your outlook.

If you have any questions about your stage or what it means for your prognosis, ask your doctor. Having a late-stage cancer can cause fear and anxiety. If you’re experiencing these feelings, seek help and support from a therapist or counselor.