Lung cancer: Each step of the deadly disease from stage 1 to stage 4

Lung cancer is a devastating diagnosis. What are the four stages of the disease? And what does it tell you about the cancer cells?

Cancer Research UK explains that the grades of lung cancer signify the extent to which cells look abnormal under the microscope.

Lung cancer: Stage 1

Stage 1 lung cancer means the cancer is small and has remained in the lung.

If the cancer is smaller than 3cm, it’s called Stage 1A.

Or the cancer is between 5cm and 7cm in size and there is more than one tumour in the same lobe of the lung.

Otherwise the cancer has spread into one or more of the follow areas just outside the lung:

• The chest wall (ribs, muscle or skin)
• The nerve close to the lung (the phrenic nerve)
• The layers that cover the heart (mediastinal pleura and parietal pericardium)
• Lymph nodes in the lung or close to the lung

Stage 3A lung cancer could mean the cancer is larger than 7cm, and it hasn’t spread to the lymph nodes, but has spread into one or more of the following areas:

• The muscle under the lung (diaphragm)
• The centre area of the chest (mediastinum)
• The heart
• A main blood vessel
• The windpipe (trachea)
• The nerve that goes to the voice box (larynx)
• The food pipe (oesophagus)
• A spinal bone
• The area where the windpipe divides (the carina)

Or the cancer is in more than one lobe of the same lung, and there may be cancer cells in the lymph nodes closed to the affected lung.

Stage 3C

The cancer is between 5cm and 7cm or has spread into one or more of the following:

• The nerve close to the lung (phrenic nerve)
• The covering of the heart (parietal pericardium)

And it has spread into lymph nodes:

• In the centre of the chest on the opposite side from the affected lung or
• At the top of the lung on the same side or opposite side or
• Above the collar bone

Or there was more than one tumour in a different lobe in the same lung.

Or the cancer is bigger than 7cm, or it has spread into the following:

• The muscle under the lung (the diaphragm)
• The centre of the chest (mediastinum)
• The heart
• A major blood vessel
• The windpipe (trachea)
• The nerve going to the voice box (the recurrent laryngeal nerve)
• The food pipe (oesophagus)
• A spinal bone
• The area where the windpipe divides (the carina)

And it has spread into the lymph nodes:

• In the centre of the chest on the opposite side from the affected lung, or
• At the top of the lung on the same side or opposite side, or
• Above the collar bone

Or there are tumours in more than one lobe of the lung.

Stage 4

Stage 4A can meany the following:

• There is cancer in both lungs
• The cancer is in the covering of the lung (the pleura) or the covering of the heart (pericardium)
• Or there is fluid around the lungs or the heart that contains cancer cells
• Or it can mean that there is a single area of cancer that has spread outside the chest to a lymph node or organ, such as the liver or bone.

Stage 4B means the cancer has spread to several areas in one or more organs.