Lung cancer is a type of cancer that begins in the lungs. Your lungs are two spongy organs in your chest that take in oxygen when you inhale and release carbon dioxide when you exhale. Lung cancer is the leading cause of cancer deaths worldwide.
What are the types of Lung cancer?
Doctors divide lung cancer into two major types based on lung cancer cells' appearance under the microscope. Your doctor makes treatment decisions based on which primary kind of lung cancer you have.The two general types of lung cancer include:
Small cell lung cancer. Small cell lung cancer occurs almost exclusively in heavy smokers and is less common than non-small cell lung cancer.
Non-small cell lung cancer. Non-small cell lung cancer is an umbrella term for several types of lung cancers. Non-small cell lung cancers include squamous cell carcinoma, adenocarcinoma, and large cell carcinoma.
What are the symptoms of Lung cancer?
Lung cancer typically doesn't cause signs and symptoms in its earliest stages. Signs and symptoms of lung cancer usually occur when the disease is advanced.Signs and symptoms of lung cancer may include:
A new cough that doesn't go away
Coughing up blood, even a small amount
Shortness of breath
Losing weight without trying
What causes Lung cancer?
Smoking causes the majority of lung cancers — both in smokers and in people exposed to secondhand smoke. But lung cancer also occurs in people who never smoked and in those who never had prolonged exposure to secondhand smoke. In these cases, there may be no clear cause of lung cancer.Doctors believe smoking causes lung cancer by damaging the cells that line the lungs. When you inhale cigarette smoke, which is full of cancer-causing substances (carcinogens), lung tissue changes begin almost immediately.
How is Lung cancer diagnosed?
If there's reason to think that you may have lung cancer, your doctor can order many tests to look for cancerous cells and rule out other conditions.Tests may include:
Imaging tests. An X-ray image of your lungs may reveal an abnormal mass or nodule. A CT scan can reveal small lesions in your lungs that might not be detected on an X-ray.
Sputum cytology. If you cough and are producing sputum, looking at the sputum under the microscope can sometimes reveal lung cancer cells' presence.
A tissue sample (biopsy). A sample of abnormal cells may be removed in a procedure called a biopsy.
How is Lung cancer managed or treated?
You and your doctor choose a cancer treatment plan based on several factors, such as your overall health, the type and stage of your cancer, and your preferences.In some cases, you may choose not to undergo treatment. For instance, you may feel that the side effects of treatment will outweigh the potential benefits. When that's the case, your doctor may suggest comfort care to treat only the symptoms the cancer is causing, such as pain or shortness of breath.