Lung cancer 101: Learn more about this deadly disease.

Lung cancer starts when abnormal cells cluster in the lungs to form a tumor. When these cells grow without order or control, destroying healthy tissue around them, the tumors are called malignant or cancerous.

Lung cancer is the leading cause of cancer-related deaths in men and women in the U.S. The American Lung Association says about 85% to 90% of lung cancer patients have had direct exposure to tobacco products.

“Those who use tobacco products are high risk,” says Ray Salomone, MD, a pulmonologist at Cleveland Clinic Mentor Medical Office Building. “Second-hand smoke, genetics and environmental conditions can also cause the disease.”

Dr. Salomone answers common questions about lung cancer:

What causes lung cancer?

Cigarette smoking is the leading cause of lung cancer.

Even those who have quit smoking are susceptible. Other risk factors include breathing secondhand smoke; exposure to asbestos or radon; and family history of lung cancer.

Are there any symptoms that point to lung cancer? Symptoms are often absent until lung cancer has advanced. In about 85% of patients, common symptoms include: shortness of breath, cough, bloody sputum, weight loss and chest pain.

What are treatment options?

Once diagnosed, it’s important to start treatment immediately. Depending on the type of lung cancer, treatment can involve surgery, chemotherapy and/or radiation.

“If you receive a lung cancer diagnosis, we’ll work together as a team,” says Dr. Salomone. “You’re not in this alone.”

Visit ClevelandClinic.org/CancerTreatmentGuides to download a free lung cancer treatment guide. To schedule an appointment with Dr. Salomone or another Cleveland Clinic pulmonologist, call 216.444.6503.