Stage 3 lung cancer

About staging

The stage of a cancer tells you how big it is and whether it has spread. Knowing the stage helps your doctor decide which treatment you need. It can also give some idea of your outlook (prognosis).

Stage 3 can be divided into 3A, 3B and 3C. Stage 3 non small cell lung cancer is sometimes called locally advanced cancer.

Stage 3A

There are 4 possible stages for stage 3A:

Stage 3A can mean the cancer is 3 cm or smaller. It:

• has not grown into the membranes that surround the lungs

• has not grown into the main airways of the lungs (bronchi)

• has spread to lymph nodes in the area where the wind pipe divides (the carina) or the space between the lungs (mediastinum) on the same side as the cancer

• has not spread to a different part of the body

Or stage 3A means one or more of the following:

• the cancer is between 3cm and 5cm

• it is smaller than 5cm and has grown into the main airway of the lung (main bronchus)

• it is smaller than 5cm and has grown into the membrane covering the lung (visceral pleura)

• it is smaller than 5cm and has caused the lung to partly or completely collapse by blocking the airway or causing inflammation of the lung tissue (pneumonitis)

• it has spread to lymph nodes in the area where the windpipe divides (the carina) or the space between the lungs (mediastinum) on the same side as the cancer

• it has not spread to a different part of the body

Or stage 3A means one or more of the following:

• the cancer is between 5cm and 7cm

• it has grown into the chest wall, (ribs, muscle or skin), the inner lining of the chest wall (parietal pleura), the nerve close to the lung (the phrenic nerve), the layers of the sac that covers the heart (mediastinal pleura and parietal pericardium)

• there are two or more areas of cancer in the same lobe of the lung

• it has not spread to the lymph nodes

• it has not spread to a different part of the body

Or stage 3A means one or more of the following:

• the cancer is larger than 7cm

• it has grown into the muscle below the lung (diaphragm), the centre area of the chest (mediastinum), the heart, a main blood vessel such as the aorta, the windpipe (trachea), the nerve that goes to the voice box (larynx), the food pipe (oesophagus), a spinal bone or the area where the windpipe divides (the carina)

• there are two or more areas of cancer in different lobes of the same lung

• it has spread to lymph nodes within the lung on the same side as the cancer and might have spread to the lymph nodes where the bronchus enters the lung (hilar lymph nodes)

• it has not spread to a different part of the body

Stage 3B

There are 4 possible stages for stage 3B:

Stage 3B can mean the cancer is 3 cm or smaller. It:

• has not grown into the membranes that surround the lungs

• has not grown into the main airways of the lungs (bronchi)

• has spread to lymph nodes in the space between the lungs (mediastinum) on the opposite side of the lung with cancer

• has spread to lymph nodes where the bronchus enters the lung (hilar lymph nodes) in the opposite lung

• it has spread to lymph nodes in the side of the neck, or above the collar bone, on either side of the body

• it has not spread to a different part of the body

Or stage 3B means one or more of the following:

• the cancer is between 3cm and 5cm

• it is smaller than 5cm and has grown into the main airway of the lung (main bronchus)

• it is smaller than 5cm and has grown into the membrane covering the lung (visceral pleura)

• it is smaller than 5cm and has caused the lung to partly or completely collapse by blocking the airway or causing inflammation of the lung tissue (pneumonitis)

• has spread to lymph nodes in the space between the lungs (mediastinum) on the opposite side of the lung with cancer

• has spread to lymph nodes where the bronchus enters the lung (hilar lymph nodes) in the opposite lung

• it has spread to lymph nodes in the side of the neck, or above the collarbone, on either side of the body

• it has not spread to a different part of the body

Or stage 3B means one or more of the following:

• the cancer is between 5cm and 7cm

• it has grown into the chest wall (ribs, muscle or skin), the inner lining of the chest wall (parietal pleura), the nerve close to the lung (the phrenic nerve), the layers of the sac that covers the heart (mediastinal pleura and parietal pericardium)

• there are two or more areas of cancer in the same lobe of the lung

• it has spread to lymph nodes in the area where the windpipe divides (the carina) or the space between the lungs (mediastinum) on the same side as the cancer

• it has not spread to a different part of the body

Or stage 3B means one or more of the following:

• the cancer is larger than 7cm

• it has grown into the muscle below the lung (diaphragm), the centre area of the chest (mediastinum), the heart, a main blood vessel such as the aorta, the windpipe (trachea), the nerve that goes to the voice box (larynx), the food pipe (oesophagus), a spinal bone or the area where the windpipe divides (the carina)

• there are two or more areas of cancer in different lobes of the same lung

• it has spread to lymph nodes in the area where the windpipe divides (the carina) or the space between the lungs (mediastinum) on the same side as the cancer

• it has not spread to a different part of the body

Stage 3C

There are 2 possible stages for stage 3C.

Stage 3C means one or more of the following:

• the cancer is between 5cm and 7cm

• it has grown into the chest wall (ribs, muscle or skin), the inner lining of the chest wall (parietal pleura), the nerve close to the lung (the phrenic nerve), the layers of the sac that covers the heart (mediastinal pleura and parietal pericardium)

• there are two or more areas of cancer in the same lobe of the lung

• has spread to lymph nodes in the space between the lungs (mediastinum) on the opposite side of the lung with cancer

• has spread to lymph nodes where the bronchus enters the lung (hilar lymph nodes) in the opposite lung

• it has spread to lymph nodes in the side of the neck, or above the collarbone, on either side of the body

• it has not spread to a different part of the body

Or stage 3C means one or more of the following:

• the cancer is larger than 7cm

• it has grown into the muscle below the lung (diaphragm), the centre area of the chest (mediastinum), the heart, a main blood vessel such as the aorta, the windpipe (trachea), the nerve that goes to the voice box (larynx), the food pipe (oesophagus), a spinal bone or the area where the windpipe divides (the carina)

• there are two or more areas of cancer in different lobes of the same lung

• has spread to lymph nodes in the space between the lungs (mediastinum) on the opposite side of the lung with cancer

• has spread to lymph nodes where the bronchus enters the lung (hilar lymph nodes) in the opposite lung

• it has spread to lymph nodes in the side of the neck, or above the collarbone, on either side of the body

• it has not spread to a different part of the body

TNM stages

TNM stands for Tumour (T), Node (N) and Metastasis (M). The staging is different depending on the type of cancer you have.

The information below is an overview of the TNM staging for all types of cancer.

• T describes the size of the tumour (cancer)

• N describes whether there are any cancer cells in the nearby lymph nodes

• M describes whether the cancer has spread to parts of the body further away from where the cancer started

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 T1 N0 M0.

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

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

• T1a-c, N2, M0

• T2a-b, N2, M0

• T3, N1, M0

• T4, N0, M0

• T4, N1, M0

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

• T1a-c, N3, M0

• T2a-b, N3, M0

• T3, N2, M0

• T4, N2, M0

Stage 3C is the same as:

• T3, N3, M0

• T4, N3, M0

Find out about TNM staging for lung cancer

Treatment

The stage of your cancer helps your doctor to decide which treatment you need. Treatment also depends on:

• your type of cancer (the type of cells the cancer started in)

• where the cancer is

• other health conditions that you have

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 one or more of the following treatments before surgery:

• ​neoadjuvant​ chemotherapy

• neoadjuvant chemotherapy with ​immunotherapy​

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 on 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 radiotherapy​ (PCR). 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