Lung cancer is the most frequently lethal
cancer in the United States. Among all causes of death, lung cancer
ranks second after heart disease for males, and third after heart and
cerebrovascular disease for females. In 2002 alone, over 150,000 people
in the United States died of lung cancer.
Cancers form when certain cells in the body
grow and multiply in an uncontrolled fashion. When such uncontrolled
growth affects lung tissues, a lung cancer forms. Lung cancer is
classified into two main types- small cell lung cancer and non-small
cell lung cancer. An estimated 80 percent of lung cancer patients have
non-small cell lung cancer.
Smoking or inhaling second hand smoke,
environmental exposures such as asbestos and radon gas, and a family
history of lung cancer increase the risk of an individual getting lung
cancer. However, some lung cancers arise in the absence of these risk
factors. Factors that may protect people from lung cancer are not
smoking, avoiding second hand smoke, a diet rich in fresh vegetables
and fruit, and limiting exposure to potential carcinogens in the
environment such as radon.
About 25 percent of people with lung cancer
report no symptoms at the time of diagnosis. In the remainder, symptoms
and signs vary, and may include breathlessness, a long lasting cough,
coughing up blood, chest pain, wheezing, repeated chest infections,
fever, and weight loss. A diagnosis of lung cancer is made on the basis
of cell type, x-ray findings and symptoms. The cancer is then staged
depending on the extent of its spread within the chest cavity and to
other parts of the body. Treatment of lung cancer depends on the cell
type and on the stage of cancer at the time of diagnosis. Treatment
typically includes surgery, chemotherapy and radiation. Survival rates
depend on the type and stage of lung cancer at the time of diagnosis.
