Lung cancer is one of the most serious and common types of cancer. It starts in the lungs, which are the two sponge-like organs in your chest that help you breathe. The cancer develops when cells in the lungs begin to grow out of control. Over time, these cells can form a tumor and may spread to other parts of the body if not treated.
While lung cancer can be life-threatening, treatments have improved in recent years, and outcomes are better when the cancer is caught early. Many people associate lung cancer with smoking, which is the leading cause, but it can also affect non-smokers.
Knowing what to look for and how the disease is diagnosed and treated can help people take action sooner, which can improve the chances of successful treatment. In this article, we’ll walk you through the basics of lung cancer—including what causes it, the types, common symptoms, how doctors diagnose it, and the options for treatment.
What Is Lung Cancer?
Lung cancer starts in the lungs, often in the lining of the airways. These cancerous cells grow quickly and can interfere with how the lungs function. In healthy lungs, oxygen is absorbed and carried throughout the body. When cancer blocks the airways or damages lung tissue, it makes it harder for the body to get the oxygen it needs.
As the cancer grows, it can move beyond the lungs to lymph nodes or other organs like the brain, liver, or bones. This spread is called metastasis. In advanced stages, lung cancer becomes more difficult to treat, which is why early detection is so important.
Lung cancer is often divided into two major types based on how the cells look under a microscope. These types grow and spread in different ways, so understanding the type helps doctors choose the best treatment.
Causes and Types
The most common cause of lung cancer is smoking tobacco. Cigarette smoke contains many harmful chemicals that damage lung cells. Over time, these damaged cells can become cancerous. Even people who don’t smoke but breathe in secondhand smoke are at risk.
Other causes include long-term exposure to air pollution, radon gas (a natural radioactive gas that can enter homes through the ground), and workplace chemicals like asbestos. Some people also have a higher risk because of family history or inherited gene mutations.
There are two main types of lung cancer:
Non-small cell lung cancer (NSCLC) is the most common type, making up about 85% of all cases. It includes subtypes like adenocarcinoma, squamous cell carcinoma, and large cell carcinoma. NSCLC usually grows and spreads more slowly than other types.
Small cell lung cancer (SCLC) is less common but more aggressive. It spreads quickly and is often diagnosed at a later stage. SCLC is strongly linked to smoking.
There are also rare types of lung cancer, including lung carcinoid tumors, which tend to grow more slowly and are less likely to spread.
Symptoms to Watch For
Lung cancer often doesn’t cause symptoms in the early stages. That’s why many cases aren’t found until the disease is more advanced. However, as the cancer grows, it can start to affect how you feel and how your body works.
Common symptoms of lung cancer include:
-
A cough that doesn’t go away or gets worse over time
-
Coughing up blood or rust-colored mucus
-
Shortness of breath, even during light activity
-
Chest pain that may get worse with deep breathing or coughing
-
Hoarseness or changes in your voice
-
Unexplained weight loss
-
Loss of appetite
-
Feeling very tired or weak
-
Repeated respiratory infections like pneumonia or bronchitis
Some people may also feel pain in their bones, have headaches, or develop swelling in the face or neck if the cancer has spread. If you have symptoms that don’t improve after a few weeks, it’s important to see a doctor, especially if you have a history of smoking or exposure to lung irritants.
How Lung Cancer Is Diagnosed
Diagnosing lung cancer usually starts with a doctor asking about your symptoms, medical history, and risk factors. A physical exam will be done, and your doctor may order imaging tests such as a chest X-ray or CT scan to look for abnormal spots in the lungs.
If something suspicious is found, further testing is needed. This may include:
-
A sputum test to check for cancer cells in mucus
-
A bronchoscopy, where a thin tube is used to look inside your airways and collect a tissue sample
-
A needle biopsy or surgical biopsy to remove a piece of lung tissue for testing
-
Blood tests and scans to see if the cancer has spread
Once the cancer is confirmed, it will be staged based on its size, location, and whether it has spread. Staging helps doctors decide how serious the cancer is and what treatments will work best.
Treatment Options for Lung Cancer
The treatment for lung cancer depends on many factors, including the type and stage of the disease, your overall health, and your personal preferences. Most people receive a combination of treatments to target the cancer from different angles.
Surgery may be used to remove part of the lung or the entire lung if the cancer is caught early and hasn’t spread. This is often followed by other treatments to reduce the risk of the cancer coming back.
Radiation therapy uses powerful beams to kill cancer cells. It’s often used before surgery to shrink the tumor or after surgery to destroy remaining cancer cells. It can also be used as the main treatment for people who can’t have surgery.
Chemotherapy involves drugs that kill cancer cells throughout the body. It’s commonly used for both non-small cell and small cell lung cancer, often in combination with other treatments.
Targeted therapy focuses on specific changes in cancer cells. If your cancer has certain genetic markers, drugs can block the proteins that help the cancer grow. These treatments usually have fewer side effects than standard chemotherapy.
Immunotherapy helps your body’s immune system recognize and attack cancer cells. This type of treatment has shown promising results for some people with advanced lung cancer.
Your care team may also recommend lifestyle changes, supportive care for symptoms, and palliative care to help manage pain and improve quality of life, especially in later stages.
