What is non-small cell lung cancer?

Clinical oncologist, Neil Bayman, explains what lung cancer is, the main types, risk factors, stages and common treatments available to you.


Lung cancer is the third most common cancer in the UK. About 47,000 people are diagnosed with it each year. Cancer that starts in the lung is called primary lung cancer.

There are two main types of primary lung cancer:

Types of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the most common lung cancer. There are three main types:

  • Adenocarcinoma is the most common type of NSCLC. It develops from cells that make mucus. It is more often found in the outer area of the lung. Although the main cause is still smoking, this type of NSCLC is more common in non-smokers.
  • Squamous cell carcinoma develops in the cells that line the airways. It is more often found in the main airways in the centre of the lungs.
  • Large cell lung cancer is a very uncommon type that usually starts in the centre of the lungs.

Non-small cell lung cancer not otherwise specified (NOS) is when the expert doctor in cell types (pathologist) cannot say for certain which type of NSCLC it is. This is uncommon.

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Symptoms of non-small cell lung cancer

If you are worried about non-small cell lung cancer, we have more information about the signs and symptoms of lung cancer. If you have any lung cancer symptoms or notice anything that is unusual for you, see your GP straight away.

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Causes of non-small cell lung cancer

Smoking tobacco is the cause of most lung cancers and the biggest risk factor. This includes smoking cigarettes, cigars and pipes. People who do not smoke can still develop lung cancer, but their risk is much lower.

If someone stops smoking, their risk of developing lung cancer gets lower over time. After about 15 years it is almost the same as a non-smoker.

Lung cancer is also more common in older people.

We have more information about the risk factors of lung cancer.

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Diagnosis of non-small cell lung cancer

People may be diagnosed with lung cancer after seeing their GP about their symptoms. If your GP thinks your symptoms could be caused by lung cancer, they will arrange tests to help make a diagnosis. These can include:

If these tests show anything abnormal, your GP will refer you to a chest specialist within 2 weeks. Sometimes they will do this before getting the result of the chest x-ray.

At the hospital, the specialist will explain any other tests you need. These may include:

  • PET-CT scan

    A PET-CT scan combines 2 types of scan. A CT takes a series of x-rays to build up a 3D picture. A PET measures the activity of cells in the body.

  • Biopsy

    During a biopsy, a doctor or nurse takes samples of cells or tissue from the abnormal area. They look at the biopsy samples under a microscope to check for cancer cells. You usually have a biopsy to find out for certain if you have lung cancer. There are different ways of collecting biopsies, including:

Waiting for tests results can be a difficult time, we have more information that can help.

Furthers tests after diagnosis

If tests show you have non-small cell lung cancer, your specialist will arrange further tests. Some of these help with the staging of lung cancer.

  • Mediastinoscopy

    mediastinoscopy is sometimes done instead of an EBUS or EUS. It lets the doctor look at the area in the middle of your chest (the mediastinum) and nearby lymph nodes. You have it under a general anaesthetic. 

  • Thoracoscopy

    thoracoscopy lets the doctor look at the lining of the lungs (pleura). It is usually done under a general anaesthetic.

  • MRI scan

    An MRI scan uses magnetism to build up a detailed picture of areas of your body.

  • Molecular testing

    Your doctors may arrange more detailed tests on cancer cells taken during a biopsy or surgery. They look for certain gene changes (mutations) in the cancer cell. This can show if the cancer cell is making an abnormal protein or has too much of a certain protein. 

    The results can tell your doctor if certain targeted or immunotherapy drugs are likely to work for you.

    Sometime doctors take a blood sample and look for pieces of cancer cells and of the tumour DNA. This is called a liquid biopsy. It is rarely done and still being researched. It may tell them more about the genetics of the cancer and help with treatment decisions.

  • Breathing tests

    If your treatment plan involves having surgery or radiotherapy your doctor will arrange breathing tests (lung-function tests) and exercise tests.

    These help doctors see how well your lungs are working. You may also have tests to check how well your heart is working.

Stages of non-small cell lung cancer

The stage of a cancer describes its size and position, and if it has spread from where it started. Knowing the stage helps your doctors advise the best treatment for you.

We have more information about the staging of lung cancer.

Treatment for non-small cell lung cancer

A team of specialists will meet to discuss the best possible treatment for you. This is called a multidisciplinary team (MDT).

Your doctor will explain the different lung cancer treatments and their side effects. They will also talk to you about the things you should consider when making treatment decisions.

You can read an overview of the different treatment options for NSCLC.

You may have a combination of treatments for NSCLC including:

  • Surgery

    It may be possible to remove NSCLC with surgery. This will depend on the size and position of the cancer.

  • Chemotherapy

    Chemotherapy may be given before or after surgery for NSCLC. Or it can be given with radiotherapy treatment. This is called chemoradiation. Chemotherapy can also be given to control symptoms when lung cancer has spread.

  • Radiotherapy

    Radiotherapy may be used instead of surgery to treat early stage NSCLC. It can also be given with or after chemotherapy. This is called chemoradiation. Radiotherapy can also be given to control symptoms.

  • Targeted therapy and immunotherapy drugs

    Targeted therapy and immunotherapy drugs can be used to treat advanced NSCLC. Your doctor will do tests on the cancer cells to find out if certain drugs are suitable for you. 

  • Tumour ablation treatments

    Tumour ablation treatments use heat or laser light to treat very early-stage lung cancers. Ablation treatment can also be used if the cancer is blocking an airway.

  • Supportive treatment

    You can have treatments to help relieve any symptoms caused by the cancer. This is sometimes called supportive care or palliative care.

After non-small cell lung cancer treatment

Follow-up after treatment

You have regular follow-up appointments after treatment.

You may get anxious before the appointments. This is natural. It may help to get support from family, friends or a support organisation.

Getting support

Everyone has their own way of dealing with illness and the different emotions they experience. You may find it helpful to talk things over with family and friends or your doctor or nurse.

Macmillan is also here to support you. If you would like to talk, you can:

Well-being and recovery

Even if you already have a healthy lifestyle, you may choose to make some positive lifestyle changes after treatment.

Making small changes such as eating well and keeping active can improve your health and well-being and help your body recover.

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About our information

  • References

    Below is a sample of the sources used in our lung cancer information. If you would like more information about the sources we use, please contact us at  cancerinformationteam@macmillan.org.uk

    National Institute for Health and Care Excellence (NICE). Lung cancer – Diagnosis and management. Clinical guideline 2019.

    Metastatic non-small cell lung cancer: ESMO clinical practice guidelines for diagnosis, treatment and follow-up. 2018.

    European Society for Medical Oncology (ESMO). Early and locally advanced non-small-cell lung cancer (NSCLC): ESMO clinical practice guidelines for diagnosis, treatment and follow-up. 2017.

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Dr David Gilligan, Consultant Clinical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We want our information to be as clear as possible. To do this, we try to:

  • use plain English
  • explain medical words
  • use short sentences
  • use illustrations to explain text
  • structure the information clearly
  • make sure important points are clear.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected.

You can read more about how we produce our information here.

Date reviewed

Reviewed: 01 November 2020
Next review: 01 November 2023

This content is currently being reviewed. New information will be coming soon.

Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.