Stage 3 lung cancer

About staging

Stage 3 is part of the number staging system. It uses the TNM system to divide cancers into stages. There are 4 stages of lung cancer, numbered from 1 to 4. Stage 3 can be divided into 3A, 3B and 3C.

Stage 3 non small cell lung cancer is sometimes called locally advanced cancer.

TNM stages

The TNM system describes:

• the size of the primary tumour (T)

• whether the cancer has spread to the lymph nodes (N)

• whether the cancer has spread to another part of the body (M)

The doctor gives each factor (T, N and M) a number. The number depends on how far the cancer has grown or spread.

So, a very small cancer which hasn't spread to the lymph nodes or elsewhere in the body may be T1mi-T1a N0 M0.

A larger cancer that has spread into the nearby lymph nodes and to another part of the body may be T3-T4 N1 M1.

In the TNM staging system, stage 3A is the same as one of the following:

• T4 N0 M0

• T3-T4 N1 M0

• T1 N2b M0

• T2-T3 N2a M0

Stage 3B is the same as one of the following:

• T2-T3 N2b M0

• T4 N2a-N2b M0

• T1-T2 N3 M0

Stage 3C is the same as:

• T3-T4 N3 M0

Find out about TNM staging for lung cancer

Stage 3A

There are 4 possible stages for stage 3A:

T4 N0 M0

Stage 3A (T4 N0 M0) can mean the cancer is bigger than 7cm.

Or it is any size and has one or more of the following features:

• it has grown into the area between the lungs in the middle of the chest (the mediastinum), the thymus gland, the windpipe (trachea), the area where the main airway divides to go to each lung (carina), the nerve that controls the voice box, a big nerve that runs between the brain, heart and digestive system (vagus nerve), the food pipe (oesophagus), or muscle below the lungs (the diaphragm)

• it has grown into the heart or major blood vessels nearby

• it has grown into blood vessels under the collar bone, the spine or a spinal bone, or nerves in the neck or shoulder

• there is more than one tumour in different lobes of the same side of the lung

The cancer has not spread to nearby lymph nodes or any other part of the body.

T3-T4 N1 M0

Stage 3A (T3-T4 N1 M0) can also mean one or more of the following:

The cancer is between 5cm to 7cm.

Or the cancer is 7cm or less and has one or more of the following features:

• it has grown into the outer lining of the chest cavity (the parietal pleura) or the chest wall (the protective structure around the lungs and other organs in the chest)

• it has grown into the outer covering of the heart (the pericardium), the nerve close to the lung (phrenic nerve) or a big vein called the azygos vein

• it has grown into nerves that come out of the spinal cord in the chest area (thoracic nerve roots) or a group of nerves around the neck area (stellate ganglion)

• there is more than one tumour in the same lobe of the lung

Or the cancer is bigger than 7cm.

Or it is any size and has one or more of the following features:

• it has grown into the area between the lungs in the middle of the chest (the mediastinum), the thymus gland, the windpipe (trachea), the area where the main airway divides to go to each lung (carina), the nerve that controls the voice box, a big nerve that runs between the brain, heart and digestive system (vagus nerve), the food pipe (oesophagus), or muscle below the lungs (the diaphragm)

• it has grown into the heart or major blood vessels nearby

• it has grown into blood vessels under the collar bone, the spine or a spinal bone, or nerves in the neck or shoulder

• there is more than one tumour in different lobes of the same side of the lung

The cancer has grown into lymph nodes within the lung or in lymph nodes in the area where the lungs join the airway (the hilum) or into both areas. These lymph nodes are on the same side as the cancer.

It hasn’t spread to any other part of the body.

T1 N2b M0

Stage 3A (T1 N2b M0) can also mean the cancer:

• is no more than 3cm at its widest part

• has not grown into the membranes that surround the lungs (pleura)

• has not grown into the main branches of the airways

• has grown into several areas of lymph nodes in the centre of the chest (mediastinum). The cancer may or may not have grown into lymph nodes just under where the windpipe branches off to each lung (subcarinal). These lymph nodes are on the same side as the cancer

• hasn’t spread to any other part of the body

T2-T3 N2a M0

Stage 3A (T2-T3 N2a M0) can also mean the cancer is between 3cm and 4cm.

Or the cancer is 4cm or less with one or more of the following features:

it involves the inner lining of the chest cavity (the visceral pleura)

• it has grown into the nearby lobe

• it involves the main airway (the main bronchus) but is not close to the area where the bronchus divides to go into each lung (carina), or part or all of the lung has collapsed or is blocked due to inflammation

Or the cancer is between 4cm and 5cm with or without the following features:

• it involves the inner lining of the chest cavity (the visceral pleura)

• it has grown into the nearby lobe

• it involves the main airway (the main bronchus) but is not close to the area where the bronchus divides to go into each lung (carina), or part or all of the lung has collapsed or is blocked due to inflammation

Or the cancer is between 5cm to 7cm.

Or the cancer is 7cm or less and has one or more of the following features:

• it has grown into the outer lining of the chest cavity (the parietal pleura) or the chest wall (the protective structure around the lungs and other organs in the chest)

• it has grown into the outer covering of the heart (the pericardium), the nerve close to the lung (phrenic nerve) or a big vein called the azygos vein

• it has grown into nerves that come out of the spinal cord in the chest area (thoracic nerve roots) or a group of nerves around the neck area (stellate ganglion)

• cancer in a single area of lymph nodes just under where the windpipe branches off to each lung (subcarinal) or in the centre of the chest (mediastinum). These lymph nodes are on the same side as the cancer.

• there is more than one tumour in the same lobe of the lung

It hasn’t spread to any other part of the body.

Stage 3B

There are 3 possible stages for stage 3B.

T2-T3 N2b M0

Stage 3B (T2-T3 N2b M0) can mean the cancer is between 3cm and 4cm.

Or the cancer is 4cm or less with one or more of the following features:

• it involves the inner lining of the chest cavity (the visceral pleura)

• it has grown into the nearby lobe

• it involves the main airway (the main bronchus) but is not close to the area where the bronchus divides to go into each lung (carina), or part or all of the lung has collapsed or is blocked due to inflammation

Or the cancer is between 4cm and 5cm with or without the following features:

• it involves the inner lining of the chest cavity (the visceral pleura)

• it has grown into the nearby lobe

• it involves the main airway (the main bronchus) but is not close to the area where the bronchus divides to go into each lung (carina), or part or all of the lung has collapsed or is blocked due to inflammation

Or the cancer is between 5cm to 7cm.

Or the cancer is 7cm or less and has one or more of the following features:

• it has grown into the outer lining of the chest cavity (the parietal pleura) or the chest wall (the protective structure around the lungs and other organs in the chest)

• it has grown into the outer covering of the heart (the pericardium), the nerve close to the lung (phrenic nerve) or a big vein called the azygos vein

• it has grown into nerves that come out of the spinal cord in the chest area (thoracic nerve roots) or a group of nerves around the neck area (stellate ganglion)

• cancer in a single area of lymph nodes just under where the windpipe branches off to each lung (subcarinal) or in the centre of the chest (mediastinum). These lymph nodes are on the same side as the cancer.

• there is more than one tumour in the same lobe of the lung

The cancer is in several areas of lymph nodes in the centre of the chest (mediastinum). The cancer may or may not have grown into lymph nodes just under where the windpipe branches off to each lung (subcarinal). These lymph nodes are on the same side as the cancer.

It hasn’t spread to any other part of the body.

T4 N2a-N2b M0

Stage 3B (T4 N2a-N2b M0) can also mean the cancer is bigger than 7cm.

Or it is any size and has one or more of the following features:

• it has grown into the area between the lungs in the middle of the chest (the mediastinum), the thymus gland, the windpipe (trachea), the area where the main airway divides to go to each lung (carina), the nerve that controls the voice box, a big nerve that runs between the brain, heart and digestive system (vagus nerve), the food pipe (oesophagus), or muscle below the lungs (the diaphragm)

• it has grown into the heart or major blood vessels nearby

• it has grown into blood vessels under the collar bone, the spine or a spinal bone, or nerves in the neck or shoulder

• there is more than one tumour in different lobes of the same side of the lung

The cancer is in a single area of lymph nodes just under where the windpipe branches off to each lung (subcarinal) or in the centre of the chest (mediastinum). These lymph nodes are on the same side as the cancer.

Or the cancer is in several areas of lymph nodes in the centre of the chest (mediastinum). The cancer may or may not have grown into lymph nodes just under where the windpipe branches off to each lung (subcarinal). These lymph nodes are on the same side as the cancer.

It hasn’t spread to any other part of the body.

T1-T2 N3 M0

Stage 3B (T1-T2 N3 M0) can also mean the cancer:

• is no more than 3cm at its widest part

• has not grown into the membranes that surround the lungs (pleura)

• has not grown into the main branches of the airways

Or the cancer is between 3cm and 4cm.

Or the cancer is 4cm or less with one or more of the features:

• it involves the inner lining of the chest cavity (the visceral pleura)

• it has grown into the nearby lobe

• it involves the main airway (the main bronchus) but is not close to the area where the bronchus divides to go into each lung (carina), or part or all of the lung has collapsed or is blocked due to inflammation

There is cancer in the lymph nodes:

• in the centre of the chest on the opposite side of the affected lung

• just under where the windpipe branches off to each lung (subcarinal) on the opposite side of the affected lung

• near muscles in the neck on one or both sides

• above the collar bone on one or both sides

It hasn’t spread to any other part of the body.

Stage 3C

Stage 3C (T3-T4 N3 M0) means one of the following:

The cancer is between 5cm to 7cm.

Or the cancer is 7cm or less and has one or more of the following features:

• it has grown into the outer lining of the chest cavity (the parietal pleura) or the chest wall (the protective structure around the lungs and other organs in the chest)

• it has grown into the outer covering of the heart (the pericardium), the nerve close to the lung (phrenic nerve) or a big vein called the azygos vein

• it has grown into nerves that come out of the spinal cord in the chest area (thoracic nerve roots) or a group of nerves around the neck area (stellate ganglion)

• there is more than one tumour in the same lobe of the lung

Or the cancer is bigger than 7cm.

Or it is any size and has one or more of the following features:

• it has grown into the area between the lungs in the middle of the chest (the mediastinum), the thymus gland, the windpipe (trachea), the area where the main airway divides to go to each lung (carina), the nerve that controls the voice box, a big nerve that runs between the brain, heart and digestive system (vagus nerve), the food pipe (oesophagus), or muscle below the lungs (the diaphragm)

• it has grown into the heart or major blood vessels nearby

• it has grown into blood vessels under the collar bone, the spine or a spinal bone, or nerves in the neck or shoulder

• there is more than one tumour in different lobes of the same side of the lung

There is cancer in the lymph nodes:

• in the centre of the chest on the opposite side of the affected lung

• just under where the windpipe branches off to each lung (subcarinal) on the opposite side of the affected lung

• near muscles in the neck on one or both sides

• above the collar bone on one or both sides

It hasn’t spread to any other part of the body.

Treatment

Stage 3 lung cancer covers many different types of tumours, which may have spread to different areas nearby the lungs. Because of this, there are lots of possible treatment options.

The treatment for small cell lung cancer differs from that for non small cell lung cancer.

Your doctor will explain these possible treatments with you. Ask as many questions as you need to.

Non small cell lung cancer

Treatment for stage 3A

Below is an overview of treatment options for stage 3A lung cancer.

If you have surgery

You might have neoadjuvant chemotherapy with ​immunotherapy before surgery.

If you are fit enough, you usually have surgery to remove:

• part of your lung (a lobectomy)

• all of the lung (pneumonectomy)

Your fitness for surgery depends on your general health and how well you are likely to recover.

After surgery, some people might be offered one or more of the following treatments:

• chemotherapy

• chemotherapy with immunotherapy

• radiotherapy

• ​targeted therapy​

This is called adjuvant treatment. Your doctor will tell you whether this is appropriate for you.

If you can’t have surgery

If you can’t have surgery, you might have radiotherapy, chemoradiotherapy (chemotherapy at the same time as radiotherapy) or sequential chemotherapy and radiotherapy. 

You might then have immunotherapy after chemoradiotherapy. Immunotherapy uses our immune system to fight cancer. It works by helping the immune system recognise and attack cancer cells.

Treatment for stage 3B and 3C

The treatment options for stage 3B and 3C are more complex and will depend on factors such as whether:

• your cancer can be removed with surgery

• it has spread to lymph nodes in the space between the lungs (mediastinum)

• how many tumours there are in the lung

It might include one or more of the following treatments:

• neoadjuvant chemotherapy with or without immunotherapy before surgery

• surgery

• chemotherapy after surgery

• chemotherapy with radiotherapy (chemoradiotherapy)

• immunotherapy

• targeted cancer drugs

Read more about treatments for lung cancer

Small cell lung cancer

If you are fit enough, you might have chemoradiotherapy for limited stage small cell lung cancer. This means you have chemotherapy at the same time as radiotherapy. Limited stage small cell lung cancer means the cancer is contained in a single area on one side of the chest.

If you are not well enough to have chemoradiotherapy, you might have chemotherapy first, followed by radiotherapy to the chest.

After you finish treatment, you might have radiotherapy to your head. This treatment is called ​prophylactic cranial irradiation​ (PCI). You have this because it is quite common for small cell lung cancer to spread to the brain. The radiotherapy aims to kill any cancer cells that may have already spread to the brain but are still too small to see on scans.

You might have prophylactic cranial radiotherapy for limited stage disease if:

• your chemotherapy or radiotherapy treatment has stopped your cancer growing

• you are well enough

Read about lung cancer treatments

Other stages

• Stage 1

• Stage 2

• Stage 4

• Limited and extensive disease (small cell cancer)

• TNM staging