Lung cancer is a type of cancer that starts in the cells of the lungs. When normal cells in the lung undergo genetic mutations, they can form tumors. These tumors can interfere with the functioning of the lungs, making it difficult for them to perform their main function of supplying oxygen to the body through the bloodstream. Early detection and treatment are critical for improving outcomes.

No two lung cancers are alike. That's why Penn Medicine doctors take time to get to know you—individualizing your care is so important to lung cancer treatment success. We listen to your concerns one-on-one. Specialists in our Lung Cancer Program break down the biology of tumor cells so that treatments can be matched to your DNA. We offer the most advanced treatments in the world and have some of the best outcomes in the nation.

Lung cancer type is determined by how tumor cells look under a microscope. The cells differ in size, shape, and chemical makeup. 

There are two main types of lung cancer. 

• Non-small cell lung cancer (NSCLC) is the most common type, making up about 85 percent of all cases. Both smokers and non-smokers can develop it. It includes several types, such as adenocarcinoma, squamous cell carcinoma, and large cell carcinoma.  
• Small cell lung cancer (SCLC) is less common but tends to grow and spread more quickly than non-small cell lung cancer. It’s typically linked to cigarette smoking and includes small cell carcinoma (oat cell cancer) and combined small cell carcinoma. 

Cancer can also develop in different areas around your lungs, not just inside them. These include lymphomas, which start in your lymph nodes, sarcomas, which are found in your bones or soft tissues, and mesothelioma, which affects the lining of your lungs. Even though these cancers are near your lungs, they aren’t referred to as lung cancer. 

Early lung cancer symptoms can be hard to notice—for some people, they’re minor enough to dismiss. Other people think the symptoms are caused by other medical issues. That's why most people are diagnosed with lung cancer after a doctor sees them for another reason. 

What you experience depends on your health and lifestyle. You may notice: 

• A new cough that you can’t get rid of or a change in an existing cough 
• Blood or reddish phlegm when you cough 
• Chest, back, or shoulder pain 
• Chronic lung infections, such as pneumonia 
• Difficulty breathing 
• Fatigue 
• Hoarseness when speaking 
• Shortness of breath or wheezing during normal activities 
• Swelling in the face, neck, arms, or chest 
• Unexplained weight loss or loss of appetite 
• Weakness or fatigue 

People with different types of lung cancer may experience additional signs or symptoms, such as leg and arm numbness, lymph node lumps, or yellowing of the skin. 

Lung cancer primarily develops due to the mutation of normal cells in the lungs, which causes them to grow uncontrollably and form tumors. Several factors can contribute to these mutations, including: 

• Smoking: Tobacco smoke, including from cigarettes, cigars, and pipes, is the leading cause of lung cancer. It contains numerous cancer-causing agents called carcinogens that damage lung cells over time. 
• Secondhand smoke: Even if you don't smoke, being exposed to secondhand smoke increases your risk of lung cancer. 
• Radon gas: This odorless, colorless gas can be released by certain rocks and soil and can accumulate in homes and buildings. Long-term exposure to high levels of radon can increase your risk of lung cancer. 
• Occupational exposure: Some substances encountered in certain workplaces, such as exposure to asbestos, arsenic, diesel exhaust, and others, can increase your risk of lung cancer when inhaled. 
• Air pollution: Breathing in polluted air, particularly in areas with high levels of pollution from vehicles, factories, or other sources, may increase your risk of lung cancer. 
• Family history and genetics: While most cases of lung cancer are related to smoking or exposure to carcinogens, a small percentage can be attributed to genetic factors and a family history of the disease. 
• Previous radiation therapy: Radiation therapy to the chest for other conditions, such as breast cancer or lymphoma, can slightly increase the risk of developing lung cancer, especially if you smoke. 
• Lung diseases: Certain lung diseases, such as chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, and tuberculosis, can increase the risk of lung cancer. 

These factors can act alone or in combination to increase the likelihood of developing lung cancer. However, it's important to note that not everyone exposed to these risk factors will develop the disease, and some people with lung cancer may not have any apparent risk factors. Getting a lung cancer screening and adopting a healthy lifestyle can help reduce your risk of lung cancer. 

Lung cancer evaluations at Penn Medicine 

When it comes to getting an accurate lung cancer diagnosis, our providers bring decades of experience. This expertise results in detailed diagnoses that help create effective short- and long-term treatment plans for each of our patients. 

World-class lung cancer care

A lung cancer diagnosis can come as a shock. At Penn Medicine, you’re never alone in your lung cancer journey. Our lung cancer team includes medical oncologists, radiation oncologists, and thoracic surgeons with decades of experience who work toward one goal: providing you with world-class lung cancer treatment options and care plans that address your specific needs. 

When you partner with us, you can expect: 

• Advanced treatments: We offer the full range of the latest lung cancer treatments, including lung-sparing surgeries, a highly precise radiation therapy called proton therapy, and therapies that target tumor DNA. 
• Fast appointments: Time is precious, so we make every second count. From same-day appointments to schedule adjustments to fit in newly diagnosed small cell lung cancer patients, you won't have to wait for answers—or needed treatments. 
• 24/7 access to lung cancer experts: Our triage nurses are just a phone call away. They help you manage treatment side effects and coordinate appointments and prescriptions. 
• Supportive smoking cessation program: Our Comprehensive Smoking Treatment Program provides guilt-free and individualized treatment strategies to help you quit smoking. 
• Outstanding care close to home: You can receive chemotherapy, radiation, and follow-up appointments at the Penn Medicine location nearest you. Our satellite offices are staffed by the same internationally renowned lung cancer experts as our downtown hospitals. 

Our lung cancer experts offer hope, compassion, and answers. Lung cancer is a complex disease, which can mean many twists and turns during treatment. But our team is by your side through it all.