Causes of Lung Cancer - Essay Example

Introduction Lung cancer is a disease in which a primary cancer develops in the tissues of the lungs and these tissues take in oxygen and release Carbon Dioxide (CO2). More people die of lung cancer than any other forms of cancer such as breast cancer or throat cancer [Mic]. There is a strong correlation between smoking and lung cancer. However many people defy this correlation by arguing that smoking is one of the reasons for lung cancer and not the only reason. They also argue that some nonsmokers also develop lung cancers and so lung cancer is not necessarily caused by smoking. Dr. Oscar Auerbach and his colleagues conducted a research (stretched over eight years) to investigate the link between lung cancer and smoking. 1500 male and female patients of lung cancer were studied and 100,000 slides of lung tissues were taken from their bodies. The degree of cancer cells was more in patients who were smokers as compared to those who were not. The research’s findings were that the degree of cell damage was directly related to the number of cigarettes smoked per day. Dr. Auerbach’s researched data contributed to the Surgeon General’s report which was published in 1964 [Ada05]. After that time period it was very common to associate lung cancer with smoking. Causes Studies targeted at deriving a relationship between cigarettes and lung cancer started in 1948 at Washington University’s School of Medicine and a student named Ernst Wynder tried connecting the dots. He did a research in 1950 that involved 649 lung cancer patients and 600 controls. Wynder discovered that the rate of lung cancer was 40 times higher in smokers than in nonsmokers. Richard Doll was a British scientist who discovered (in the same year) evidence supporting the causal relationship between smoking and lung cancer. Doll researched on physicians, both who smoked and did not smoked and waited for years to see if any of them developed lung cancer. Undoubtedly the ones to who did develop lung cancer were smokers [Joh1]. There were a total of 158,900 deaths in the USA in 1999 because of lung cancer and this figure included men and women both. The death toll for lung cancer patients in 1999 world over was 1 billion. But lung cancer was not this common in the 1800s and it was rare. In 1929, a German physician named Fritz Lickint pointed out in his report that lung cancer patients were majorly smokers and he was so disturbed by his findings that he started an anti-tobacco movement in Germany to discourage smoking [Han01]. Before 1996, studies on causes of lung cancer derived a relationship between lung cancer and smoking but the causes of lung cancer were not narrowed down to the cellular level. In 1996, Dr. Moonshong Tang and Dr. Gerd Pfeiffer explained how smoking affects cells and causes cancer. Both the doctors explained that cigarettes contain a chemical called benzo pyrene and it damages p53, a protein found in lung cells. This protein is exactly the same as the protein found in lung cancer patients. The function of p53 is that it controls the abnormal growth of cells which can result in tumors. Benzo pyrene damages p53 and the abnormal growth of cells cannot be controlled because of this [Ada05]. Specialists have worked on deriving a causal relationship between smoking and lung cancer. But epidemiological research has been done predominantly for deriving this relationship. Under epidemiological research, subjects are given the freedom of self-reporting their smoking habits and they do not have good memories as a result of which facts are under- or overstated. Smoking can cause other types of cancer as well: such as nasal cavity cancer, liver cancer and stomach cancer. Lung cancer can be caused by all forms of smoking such as cigarettes, cigars, pipes or bidis (tobacco wrapped in plant). When we say smoking causes cancer people generally assume that we are referring to active smoking. This is not plausible as lung cancer is also caused by passive smoking [Con11]. Passive smoking is when non-smokers inhale the tobacco smoke because they are surrounded by smokers. Passive smokers stand a 24% chance of developing lung cancer as per research. 3000 lung cancer patients who die each year in the USA are passive smokers. As for the active smokers, research shows that 90% of lung cancer is attributable to smokers. The greater the number of cigarettes a smoker smokes per day, the greater the risk of developing lung cancer. The number of cigarette packets consumed per day multiplied by the number of years smoked is referred to as pack-years risk by doctors. The greater the pack years risk, the greater the chances of developing lung cancer. There are 4000 harmful chemicals in tobacco smoke and many of these are identified as carcinogens. The most dangerous carcinogens in tobacco smoke are nitrosamines and polycyclic aromatic hydrocarbons [Mel11]. Many scientists believe cancers are developed because of two main reasons: exposure to carcinogens and our personal vulnerability (which has to do with genetics). Personal vulnerability depends on a person’s family history. People whose family members have had lung cancer are more prone to it than those who do not have a family history of lung cancer. Moreover, people who survive lung cancer, stand a chance of developing it again. Other factors also increase the chances of developing lung cancer. For instance if a person has other pulmonary or lung diseases (like bronchitis and emphysema), he is more vulnerable to lung cancer. Diseases like bronchitis and emphysema are an indication that cancer cells might be developing in the lungs. Tuberculosis is curable but it scars the lungs which makes them suitable areas to be attacked by cancer cells. The causes of lung cancer that have to do with a person’s genetic blueprint are unavoidable as nobody can change his genes. But some of the causes of lung cancer like smoking and pollution can be significantly controlled [Car07]. One of the causes of lung cancer is pollution. If carbon emission by vehicles is reduced then people will have a cleaner and safer environment to live in. They will be at a lesser risk of lung cancer. Light cigarettes are better than the traditional cigarettes which are more strong and dangerous. It is very difficult for habitual smokers to give up smoking. There are people who smoke for thrill and there are others who are hard core smokers. Of these two types, hardcore smokers are more susceptible to lung cancer as they smoke more cigarettes per day and very addicted to smoking. If they do try to quit smoking, they experience withdrawal symptoms such as nausea and shivering. These withdrawal symptoms make it very difficult for a person to quit. Conclusion Smoking is the leading cause of lung cancer but it is not the only cause. There are definitely other causes of lung cancer such as pollution, family history and diseases like bronchitis and tuberculosis that can trigger lung cancer. Tobacco smoke contains harmful chemicals like tar and nicotine which cause addiction in smokers. When smokers become addicts, they consume more cigarettes per day which increases their risk of developing lung cancer. People who live with smokers (that is passive smokers) are very vulnerable to lung cancer. Many of the physicians advise not to smoke especially in a house where children live. There is a causal relationship between smoking and lung cancer but the fact that nonsmokers also develop lung cancer cannot be ignored. Works Cited Mic: , (Michael Sarg), Ada05: , (Adams), Joh1: , (Johnson), Han01: , (Witschi), Con11: , (Connie Henke Yarbro), Mel11: , (Stöppler), Car07: , (Carmen Ferreiro), Read More