Stages of non–small cell lung cancer

Staging describes or classifies a cancer based on how much cancer there is in the body and where it is when first diagnosed. This is often called the extent of cancer. Information from tests is used to find out the size of the tumour, which parts of the organ have cancer, whether the cancer has spread from where it first started and where the cancer has spread. Your healthcare team uses the stage to plan treatment and estimate the outcome (your prognosis).

The most common staging system for non–small cell lung cancer is the TNM system. For non–small cell lung cancer there are 5 stages – stage 0 followed by stages 1 to 4. Often the stages 1 to 4 are written as the Roman numerals I, II, III and IV. Generally, the higher the stage number, the more the cancer has spread. Talk to your doctor if you have questions about staging.

When describing the stage, doctors may use the words local, regional or distant. Local means that the cancer is only in the lung and has not spread to other parts of the body. Regional means the cancer has spread to lymph nodes or other parts of the chest on the same side of the body as the cancer. Distant means the cancer has spread outside the chest to other parts of the body.

If cancer cells have been found in mucus and other material coughed up from the lungs (called sputum) or in fluid used to wash out the lungs but a tumour can’t be found by an imaging test or bronchoscopy, the cancer is called an occult (hidden) lung cancer.

Find out more about staging cancer.

Cancer cells are found only in the lining of the airway or the air sacs of the lung.

The tumour is within the lung and is 3 cm or smaller.

Stage 1A can be divided into the following stages:

Stage 1A1 – The tumour in the lung is 1 cm or smaller.

Stage 1A2 – The tumour in the lung is larger than 1 cm but not more than 2 cm.

Stage 1A3 – The tumour in the lung is larger than 2 cm but not more than 3 cm.

The tumour in the lung is larger than 3 cm but not more than 4 cm. It may also have:

• grown into the main airway but not the area where the windpipe (trachea) divides into the left and right bronchi
• grown into the inner membrane covering the lungs (called the visceral pleura)
• caused a collapsed lung or it has blocked a bronchus and caused an inflammation of the lung tissues (obstructive pneumonitis) in part or all of the lung

The tumour in the lung is larger than 4 cm but not more than 5 cm or it has:

• grown into the main airway but not the area where the windpipe divides into the left and right bronchi
• grown into the inner membrane covering the lungs
• caused a collapsed lung or it has blocked a bronchus and caused an inflammation of the lung tissues in part or all of the lung

The tumour in the lung is 5 cm or smaller and it has spread to lymph nodes near the bronchi.

OR

One of the following:

• The tumour is larger than 5 cm but not more than 7 cm.
• The tumour has grown into the outer membrane covering the lungs (called the parietal pleura), the chest wall, the main nerve that runs to the diaphragm (called the phrenic nerve) or the outer membrane covering the heart (called the parietal pericardium).
• There are 2 or more tumours in the same lobe of the lung.

The tumour in the lung is 5 cm or smaller and it has spread to lymph nodes beside the windpipe on the same side of the body as the tumour, or to lymph nodes below the area where the windpipe divides into the left and right bronchi, or both.

OR

The tumour is larger than 5 cm and one of the following:

• The cancer has spread to lymph nodes near the bronchi.
• The tumour has grown into any of the following: the diaphragm, the mediastinum, the heart or large blood vessels near the heart, the windpipe, a main nerve that runs to the larynx, the esophagus, a bone in the spine (vertebra) or the area where the windpipe divides into the left and right bronchi.
• There are 1 or more other tumours in the same lung.

The tumour is 5 cm or smaller and the cancer has spread to the lymph nodes on the opposite side of the windpipe or lung or to lymph nodes in the lower part of the neck.

OR

The tumour is larger than 5 cm or there are 1 or more other tumours in the same lung. The cancer has also spread to lymph nodes beside the windpipe on the same side of the body as the tumour, or to lymph nodes below the area where the windpipe divides into the left and right bronchi, or both.

The tumour is larger than 5 cm or there is more than 1 tumour in a different lobe of the lung. Cancer has also spread to the lymph nodes on the opposite side of the windpipe or lung or to lymph nodes in the lower part of the neck.

The cancer has spread to other parts of the body (called distant metastasis). This is also called metastatic non–small cell lung cancer.

Stage 4A – Any of the following:

• Cancer has spread to the other lung.
• Cancer has spread to the pleura or pericardium.
• There is extra fluid within the pleura or pericardium (called an effusion).
• The cancer has spread and there is 1 new tumour growing outside of the chest (thorax).

Stage 4B – The cancer has spread and there are 2 or more tumours growing outside of the chest.

Recurrent non–small cell lung cancer means that the cancer has come back after it has been treated. If it comes back in the same place that the cancer first started, it’s called local recurrence. If it comes back in tissues or lymph nodes close to where it first started, it’s called regional recurrence. It can also recur in another part of the body. This is called distant metastasis or distant recurrence.