Lung cancer is a growth of abnormal cells inside the lungs. The cells divide and grow faster than healthy cells, forming into clusters called tumours. The cancer cells replace and destroy the healthy tissue around them. Lung cancer can also spread (metastasize) to other parts of the body.
Nearly 30,000 Canadians will be diagnosed with lung cancer this year, and they need our help. Our goal? Giving them a fighting chance by eliminating the barrier of stigma.

Look for the Stigma Spotlight in each section of this content. It will help you learn how stigma affects people with lung cancer – a devastating disease that nobody deserves.
Get help now
If you (or a loved one) have been diagnosed with lung cancer and need assistance coping, we are here to help. Skip to our Coping with Lung Cancer section, or reach out to our Lung Health Line for free one-on-one guidance from a Certified Respiratory Educator.
The Science of Lung Cancer
Your lungs take in oxygen when you inhale, and release carbon dioxide when you exhale. When learning about lung cancer, it’s helpful to go a little deeper and get to know our lungs at the cellular level.
Like your other organs, your lungs are made of cells. Healthy cells grow and divide over time, and even die. The trouble starts when your cells start to grow uncontrollably. This happens because the DNA inside your cells changes (think aging) or becomes damaged (think smoke, pollution or other things in your environment or lifestyle). Once cells turn cancerous and continue to quickly divide, tumours form.
Lung cancer can start anywhere in the lungs, from the bronchus (which brings air in) to the pleura (the thin tissue that covers the lungs and lines the chest cavity) and anywhere in between.
Lung cancer types
Non-small cell lung cancer (NSCLC) | Small cell lung cancer (SCLC) | |
---|---|---|
How common is it? | This is the most common type of lung cancer, accounting for around 85% of cases. | This type of lung cancer is less common, accounting for around 10 to 15% of cases. |
How does it spread? | NSCLC usually spreads more slowly than other lung cancers. | SCLC is usually more aggressive and can result in larger tumours. |
Why’s it called that? | “Non-small” doesn’t have anything to do with the size of the tumours or extent of the cancer. It refers to the kind of cells found in the cancer, and how they look under the microscope. | “Small” doesn’t have anything to do with the size of the tumours or extent of the cancer. It refers to the kind of cells found in the cancer, and how they look under the microscope – small and round. |
Major sub-types | - Adenocarcinoma (the most common form of lung cancer in general) - Squamous cell carcinoma - Large cell carcinoma | - Small cell carcinoma - Mixed small cell/large cell - Combined small cell carcinoma |
How it’s staged | Stage I, II, III, or IV. | Limited Stage, Extensive stage |
Treatment options | Chemotherapy, surgery, and radiation therapy are all common treatments for non-small cell lung cancer. Targeted treatments are an option for some patients. These drugs affect cancer’s ability to grow by targeting specific genes or other factors. To find out if you qualify for any of these treatments, you will need to undergo molecular testing. Immunotherapy, a kind of treatment that boosts the immune system’s ability to defend against cancer, is an option for some patients. Like targeted treatments, immunotherapies require further testing. | Systemic (whole body) treatments like chemotherapy are more effective in fighting small cell lung cancer than localized treatments like surgery. Surgery is rare, but may be an option if the cancer has not reached the lymph nodes. Depending on the stage of the cancer, radiation therapy may be used in combination with chemotherapy (chemoradiation), or could be used to prevent the spread of cancer to the brain. There are currently no immunotherapy or targeted treatments for SCLC. |
There are other types of lung cancer too, though they are less common. They include:
- Carcinoid (neuroendocrine) tumours, which grow slowly and rarely spread
- Soft-tissue sarcoma, which grow very slowly, usually in the pleural membranes
- Pleural mesothelioma, which is rare and usually linked to asbestos exposure
When cancer spreads from the lungs
When cancer spreads to the lungs
Early Lung Cancer Symptoms
- A stubborn cough that won’t go away (which could make it difficult to sleep)
- Coughing up blood or rust-coloured sputum (phlegm)
- Laboured breathing, shortness of breath, or wheezing
- Chest pain (deep in the lungs when lifting, coughing, or laughing)
As you begin treatment, the symptoms you experience may happen because of the disease itself, or they could be side effects of your treatment.
What causes lung cancer?
Smoking
Radon
Workplace exposures
Genetics

Lung Cancer Screening
“Screening” means checking for cancer before symptoms develop, even if you feel healthy. Screening can help detect cancer in its earliest stages.


Diagnosis and Staging
Being diagnosed with lung cancer is often life-changing, and emotional distress is common. Understanding the steps and procedures can help you feel more in control, prepare you to advocate for yourself during your treatment.


Navigating Your Lung Cancer Care
The cancer care system can seem overwhelming at first, but we’re here to help you navigate it in a way that makes you feel empowered and supported.



Treatment
Your treatment team will consider a number of factors when choosing treatments that will fight your cancer most effectively. They will consider your overall health, age, and personal situation.


Questions and Answers About Coping with Lung Cancer
The questions we list here are the top coping questions reported by people with lung cancer. Our answers provide some basic information, but we encourage you to discuss any concerns or questions with your oncologist and other members of your cancer care team.