Select a condition Absence seizures Acne ADHD Age-related macular degeneration AIDS Alzheimer's disease AMD Amebic dysentery Anal tears Angina, stable Angina, unstable Ankle sprain Anorexia Anxiety Appendicitis Arthritis Asthma in adults Asthma in children Athlete's foot Atrial fibrillation Attention deficit hyperactivity disorder (ADHD) Autism Back pain Bacterial vaginosis Bad breath Bedsores Bedwetting Bell's palsy Benign prostatic hyperplasia Bipolar disorder Bladder infection in women Blood pressure Breast cancer Breast pain Bronchiectasis Bronchiolitis Bronchitis Bulimia Bunions Burning mouth syndrome Burns and scalds Canker sores Cardiac arrest Carpal tunnel syndrome Cataracts Cellulitis and erysipelas Chickenpox Childbirth, heavy bleeding Childbirth, tear or cut Chlamydia Chronic bronchitis Chronic fatigue syndrome Chronic obstructive pulmonary disease Chronic prostatitis Chronic tension type headache Cold sores Colic in babies Colon and rectal cancer Colon and rectal cancer screening Colonic diverticular disease Common cold Conjunctivitis Constipation in adults Constipation in children COPD Crib death Deep vein thrombosis Dementia Depression in adults Depression in children Diabetes, type 1 Diabetes, type 2 Diarrhea in adults Diarrhea in children Diverticular disease Ear infection, middle ear Ear infection, outer ear Ear infection with discharge Ear infection with fluid Ear pain during air travel Ear wax Eczema Emphysema Endometriosis Enlarged prostate Epilepsy Episiotomy Erection problems Essential tremor Febrile seizures Fertility problems Fibroids Flu Gallstones Genital herpes Genital warts GERD GERD in children Glaucoma Gonorrhea Gout Group B streptococcus H. pylori infection Halitosis Hay fever Headache, chronic tension type Head lice Heart and circulation problems in diabetes Heart attack Heartburn Heart failure Heavy periods Heel pain Hemorrhoids Hepatitis B Hepatitis C Hernia Herpes, genital Herpes simplex eye infection High blood pressure High blood pressure in pregnancy High cholesterol HIV infection Hyperactivity IBS Incontinence in women Infection in newborn babies Infertility Influenza Insomnia in adults Irritable bowel syndrome Jaundice in newborn babies Jet lag Kidney infection Kidney stones Leg cramps Leg ulcers Lewy body dementia Lung cancer Lyme disease Macular degeneration Malaria prevention Manic depression Mastalgia Measles, mumps and rubella: prevention Melanoma Meniere's disease Meningococcal disease Menopause Migraine in adults Migraine in children MMR prevention Morning sickness Multiple sclerosis Nail infection, fungal Neck pain Nicotine addiction Non-Hodgkin's lymphoma Nosebleeds in children Obesity Obsessive-compulsive disorder OCD Oral thrush Osteoarthritis Osteoporosis Ovarian cancer Painful periods Pancreas cancer Panic attacks Parkinson's disease PCOS Pelvic inflammatory disease Perineal care Peripheral vascular disease Pneumonia Polycystic ovary syndrome Postpartum depression Postpartum hemorrhage Post-traumatic stress disorder Preeclampsia Pregnancy, nausea Premature birth Pressure sores Prostate cancer Prostatitis, chronic Psoriasis PTSD Raynaud's disease Rectal cancer screening Recurrent cystitis Reflux in children Rheumatoid arthritis Scabies Schizophrenia Seasonal allergy Shoulder pain Sickle cell anemia Sickle cell disease SIDS Sinusitis Skin cancer (melanoma) Skin cancer (squamous cell) Sleep apnea Sleep problems in children Slipped disk Smoking Sore throat Stomach ulcers Stress headache Stress incontinence Stroke, emergency care Stroke prevention Sudden infant death syndrome Swimmer's ear Tennis elbow Tension headache Testicular cancer Thrush (oral) Tic douloureux Tinnitus Tonsillitis Toxoplasmosis in pregnancy Trigeminal neuralgia Underactive thyroid Urinary tract infections in children Varicocele Varicose veins Vascular dementia Warts Whiplash Wisdom teeth, impacted Wrinkles Yeast infection, vagina

Select treatment area Bladder & Kidneys Blood Brain & nervous system Cancer Children's health Diabetes Digestive system Ear, nose & throat Eating & weight Eyes Fertility Heart and circulation Hormones Infections Lungs & breathing Men's health Mental health Mouth Muscles & bones Pregnancy & childbirth Sexual health Skin Sleep Staying healthy Travel health Women's health

It can be devastating to find out that you or someone close to you has lung cancer. It's a serious illness in which some of the cells in your lungs have started to grow out of control, invading and destroying other cells. In the weeks and months to follow, you will probably have many different emotions, including anxiety about what lies ahead.

Almost before you have had time to take in what the doctors have told you, you will be offered a range of tests and treatments that aim to get rid of your cancer or relieve your symptoms, or both. The treatment you get will depend on the type of lung cancer you have, how large it is, and whether it has spread. A lot will also depend on how you feel about your illness and how you would like it to be treated.

We hope our information will answer your questions about lung cancer. And it may help you to talk with your doctor about the best treatments for you.

Some people want to know more about their cancer than others. Some will choose to have treatments that may help them live longer but which could have unpleasant, sometimes harmful, side effects. Other people prefer to enjoy as much of life as they can.¹

There's no right or wrong way for you to deal with your cancer. The most important thing is for you to feel comfortable with the decisions you make. It's also essential that your medical team and those who care about you listen to what you say and respect your wishes.

• Lung cancer is the second most common type of cancer in both men and women (not counting skin cancer). It is the leading cause of deaths from cancer in the United States.²
• By the time they are diagnosed, most people's lung cancer has spread outside of the lungs.
• You will be offered a range of treatments that aim to get rid of the cancer and improve your symptoms.
• Most treatments have side effects. These should be weighed against the benefits of the treatment.
• Cigarette smoking is the most common cause of lung cancer. The best way to prevent lung cancer is not to smoke.

You have two lungs. They sit in your chest, inside your rib cage, one on each side of your heart. They are covered by a layer of moist tissue called the pleura.

Your lungs are a little like two spongy, elastic bags that fill up with air as you breathe in. They empty as you breathe out. The right lung is divided into three sections. These sections are called lobes. The left lung has two sections (or lobes).

Keeping your lungs healthy is important. They take oxygen from the air you breathe, which your blood then carries around your body. When you breathe out, they get rid of carbon dioxide, which is a waste product made by your body.

Here's how air travels into your lungs.

Your windpipe (trachea) is the air passage that leads from your throat into your chest. In your chest, your windpipe divides into two smaller airways (called bronchi). Each airway leads into a lung.

Inside your lungs, the airways divide into even smaller airways (called bronchioles). At the end of each of these smaller airways are little air sacs (called alveoli).

When you breathe in, air travels down your windpipe, through the airways, into your lungs and then into the smaller airways and the air sacs.

The air sacs in your lungs are connected to the network of blood vessels that surrounds your lungs. Oxygen from the air you breathe in passes through the thin walls of the air sacs and into these blood vessels. Then, the oxygen is carried back to your heart and pumped around your body. At the same time, carbon dioxide (which is made as a by-product of breathing) passes from your blood into the air sacs. The carbon dioxide leaves your body when you breathe out.

Also inside your chest, lying between your lungs, are:

• Your heart
• The main blood vessels that carry blood to and from your heart and the rest of your body
• The tube that carries food from your mouth to your stomach. This tube is called the esophagus.

When your body's cells are healthy, they divide, grow old, then die and are replaced in an orderly way. But when you get cancer, your cells grow and multiply too quickly.

This means your cells don't have time to develop into normal, healthy cells. They may be the wrong shape and may not work properly. And they tend to lie on top of one another instead of in neat rows. Lung cancer can start almost anywhere in your lungs, but it usually starts in your airways. Abnormal cells tend to group together and form a lump, which is called a tumor. This slowly gets bigger.

Nearly all types of lung cancer can spread to other parts of your body and form more tumors. These are called secondary tumors. You may hear doctors talk about metastasis. This is the word doctors use to describe the way cancer spreads.

To find out more, see How lung cancer spreads.

Doctors divide lung cancer into two kinds. This is based on what the cancer cells look like when samples of cells from a lung are examined in the laboratory.

The two kinds of lung cancer are:

• Non-small-cell lung cancer (NSCLC). This is the main kind. About 4 in 5 cases of lung cancer are this type. It can start in different parts of the lung. There are three different types of non-small-cell cancer. To find out more, see Different kinds of non-small-cell lung cancer
• Small-cell lung cancer (SCLC). About 1 in 5 cases of lung cancer are this type. Doctors also call this sort of lung cancer oat cell cancer because it's made up of small cells that look like oats. These cells grow and spread more quickly than the cells in non-small-cell lung cancer.³

Some things increase your chance of getting lung cancer. Doctors call these things risk factors. Having a risk factor doesn't mean you'll definitely get lung cancer. It just means you're more likely to get it than someone who doesn't have the risk factor.

The main risk factor for lung cancer is smoking. But sometimes people who have never smoked get lung cancer. To learn more, see Risk factors for lung cancer.