Lung cancer and emphysema are two distinct diseases that cause damage to the lungs. Emphysema does not, however, lead to lung cancer. The relationship between these diseases is instead one based upon mutual risk factors, namely smoking. A person with emphysema is ultimately at greater risk of developing lung cancer. This is because smoking complications can extend from lung tissue damage (emphysema) to lung cell damage (cancer).
Emphysema is a chronic obstructive pulmonary disease marked by lung tissue destruction and irreversible enlargement of air sacs, or alveoli. Those air sacs deliver oxygen to and remove carbon dioxide from the blood. Alveoli walls lose elasticity as they grow progressively larger. In effect, they cannot properly fill with fresh air, which leads to breathing impairment. This is one reason why shortness of breath is often a classic symptom of emphysema.
The stages of emphysema usually occur gradually, and signs of the disease commonly develop after age 50. Lung damage, however, may occur before symptoms appear. Smoking is one of the leading causes of emphysema, accounting for more than half of all cases worldwide. Sustained exposure to lung irritants, such as dust and industrial fumes, as well as living in areas of poor air quality, can also lead to the disease.
A direct relationship does not exist between lung cancer and emphysema because one disease does not cause the other, and they occur independently of each other. They share risk factors, however, that determine their prevalence and thus create an indirect relationship. Those risk factors may explain why lung cancer is likely to develop in someone who already has emphysema.
Lung cancer is characterized by malignant cell growth in lung tissue. In healthy people, bronchial airways are lined with two layers of cells. Those layers begin to increase with lung cancer, and mucus-secreting cells disappear and are replaced with a mass of disorganized cells with abnormal nuclei. The growing mass eventually penetrates the underlying cell membrane, and cancer cells may then travel to other parts of the body.
Cancer in the lungs is categorized into two general types that determine its course of treatment: small cell lung carcinoma and non-small cell lung carcinoma. The majority of lung cancer cases are caused by exposure to either tobacco smoke, radon or asbestos. Similar to emphysema, smoking is the foremost contributor to lung cancer.
The risk for developing lung cancer increases with emphysema even in people who have never smoked. This is likely due to the sharing of additional risk factors, such as genetics, occupational exposures and environmental pathogens. Lung cancer and emphysema share physiological characteristics as well. Among these are stiffness of the lungs, decreased oxygen to the blood and chronic coughing.
Lung cancer and emphysema are also linked in terms of patient prognosis. Patients with both diseases have much lower survival rates than those with just emphysema. An emphysema prognosis depends upon many factors, including lifestyle and overall health. Emphysema treatment options include the use of steroids and supplemental oxygen, moderate aerobic activity and taking measures to prevent chest infections. Treatment of lung cancer, on the other hand, largely depends upon the size and location of the tumor.
