Lung cancer affects more than 200,000 Americans each year. Although cigarette smoking is the main cause, anyone can develop lung cancer. Lung cancer is always treatable, no matter the size, location, whether the cancer has spread, and how far it has spread.

Because lung cancer is associated with smoking, patients may feel that they won’t receive much support or help because they believe that others will think that their behavior caused the disease. The truth is that most smokers do not develop lung cancer, and not all people diagnosed with lung cancer smoke. Lung cancer is a disease that can affect anyone. In fact, most people who get lung cancer today have either stopped smoking years earlier or never smoked.

Lung cancer is a disease in which certain cells in the lungs become abnormal and multiply uncontrollably to form a tumor. Lung cancer may not cause signs or symptoms in its early stages. Some people with lung cancer have chest pain, frequent coughing, blood in the mucus, breathing problems, trouble swallowing or speaking, loss of appetite and weight loss, fatigue, or swelling in the face or neck. Additional symptoms can develop if the cancer spreads (metastasizes) into other tissues. Lung cancer occurs most often in adults. Most people who develop lung cancer have a history of long-term tobacco smoking; however, the condition can occur in people who have never smoked.

Lung cancer is generally divided into two types, small cell lung cancer and non-small cell lung cancer, based on the size of the affected cells when viewed under a microscope. Non-small cell lung cancer accounts for 85 percent of lung cancer, while small cell lung cancer accounts for the remaining 15 percent.

lung cancer is the second most commonly diagnosed cancer, after breast cancer, accounting for about one-quarter of all cancer diagnoses. It is estimated that more than 222,500 people develop lung cancer each year. Approximately 6.6 percent of individuals will develop lung cancer during their lifetime. An estimated 72 to 80 percent of lung cancer cases occur in tobacco smokers. Lung cancer is the leading cause of cancer deaths, accounting for an estimated 27 percent of all cancer deaths in the United States.

Cancers occur when genetic mutations build up in critical genes, specifically those that control cell growth and division (proliferation) or the repair of damaged DNA. These changes allow cells to grow and divide uncontrollably to form a tumor. In nearly all cases of lung cancer, these genetic changes are acquired during a person’s lifetime and are present only in certain cells in the lung. These changes, which are called somatic mutations, are not inherited. Somatic mutations in many different genes have been found in lung cancer cells. In rare cases, the genetic change is inherited and is present in all the body’s cells (germline mutations).

Mutations in many other genes have been found to recur in lung cancer cases. Most of these genes are involved in the regulation of gene activity (expression), cell proliferation, the process by which cells mature to carry out specific functions (differentiation), and apoptosis.

Researchers have identified many lifestyle and environmental factors that expose individuals to cancer-causing compounds (carcinogens) and increase the rate at which somatic mutations occur, contributing to a person’s risk of developing lung cancer

The greatest risk factor is long-term tobacco smoking, which increases a person’s risk of developing lung cancer 25-fold. Other risk factors include exposure to air pollution, radon, asbestos, certain metals and chemicals, or secondhand smoke; long-term use of hormone replacement therapy for menopause; and a history of lung disease such as tuberculosis, emphysema, or chronic bronchitis. A history of lung cancer in closely related family members is also an important risk factor; however, because relatives with lung cancer are frequently smokers, it is unclear whether the increased risk is the result of genetic factors or exposure to secondhand smoke

Black men are about 15% more likely to get lung cancer than white men. Black women are 14% less likely to get lung cancer when compared with white women. People age 65 and older are more likely to develop the disease. The average age of diagnosis is 70.

Lung cancer is the second most common cancer and the leading cause of cancer death for men and women. It is estimated that 135,720 (72,500 men and 63,220 women) deaths from this disease will occur in the united states.