PRESENTATION OUTLINE
The Big Picture of Lung Cancer
The major cause of cancer deaths in men and women is lung cancer; this situation is relatively new and is mainly due to cigarette smoking. In 1876, a machine was invented to make rolled-up cigarettes and thus provided cheap tobacco products to almost everyone. At that time, lung cancer was relatively rare. Smoking dramatically increased and so did lung cancers following this innovation. Currently about 90% of all lung cancers are related to smoking. Radon gas, pollution, toxins, and other factors contribute to the remaining 10%.
How Does Smoking Cause Lung Cancer?
Cigarettes and cigarette smoke contains over 70 cancer-causing chemicals (carcinogens). In addition, cigarette smoke damages and can kill hair-like projections on airway cells termed cilia. The cilia normally sweep out toxins, carcinogens, viruses, and bacteria. When the cilia are damaged or destroyed by smoke, all of these items may accumulate in the lungs and may cause problems such as infections or lung cancer.
Symptoms of Lung Cancer
Unfortunately, lung cancers often have either no early symptoms or nonspecific early symptoms that people often dismiss. Early nonspecific symptoms may include one or more of the following:
Cough (chronic, recurrent)
Fatigue
Weight loss
Short of breath or wheezing
Coughing up phlegm that contains blood
Chest pain
Screening for Lung Cancer
Screening for lung cancer is usually done by three methods:
A physical exam, patient history of smoking, and a chest X-ray
A sputum cytology exam (cells examined by a pathologist)
A spiral CT exam
A study by researchers suggested that people aged 55 to 74 years old who had smoked at least one pack of cigarettes a day for 30 or more years may benefit from a spiral CT study of the lungs. At best, the screening methods find about 30% of lung cancers leaving the bulk (about 70%) cancers of lung undetected.
Lung Cancer Diagnosis
If the screening tests suggest a person has lung cancer, definitive diagnostic tests may be done by a pathologist. The pathologist will examine the patient’s lung cells in sputum, phlegm, or from a biopsy sample to type and stage the cancer.
Types of Lung Cancer
There are only two major types of lung cancers, small cell and non-small cell lung cancers. Non-small cell lung cancers account for about 90% of all lung cancers and are less aggressive (spread to other tissues and organs slowly) than small cell cancers.
Survival Rates for Lung Cancer
The American Cancer Society statistics are currently based on people diagnosed between 1998 and 2000 so the data may not reflect the effects of newer treatments. The data indicates that survival rates of patients living 5 years after being diagnosed with non-small cell cancers was dependent on the stage of the disease. Stage I was about 49% while stage IV survival was about 1%. Small cell lung cancers are more aggressive and the data, like that for non-small cell lung cancers, is not reflective of current survival rates. However, even some data collected as late as 2008 indicates slow progress in increasing 5-year survival rates:
