Lung cancer is a grave problem for today's American people. The American Cancer Society estimates that in 1992, 49,000 people in America were diagnosed with new cases of this disease, and that 41,100 people previously diagnosed with lung cancer died (Coggon & Acheson, 1992). Therefore, the mortality rate among people with lung cancer shown an alarming increase, when the number of deaths among those suffering from almost all other types of cancer has remained the same or declined.
Mortality Rates and Key Risk Factors Associated with Lung Cancer in the USA
Smoking by adult Americans aged 20 and over is at a peak every year. White men and women in their early 20s have the highest smoking rate, namely 40 percent, in comparison to any other group in the country. There are fewer young blacks of both sexes, who smoke, than whites, and there are fewer smokers among Hispanics than among blacks or whites, although smoking among young Hispanic women and men is increasing (Spiro, 1990).
Other causes of lung cancer are of course asbestos, radioactivity, and industrial chemicals affecting people separately and in combination with smoking. Still, there are other causes, which are air pollution and so-called side stream smoke. The latter is smoke nonsmokers passively inhale in the presence of smokers. However, groups at risk as a result of known causes other than smoking are comparatively small. In addition, many authorities find evidence for suspected causes, including passive smoking, inconclusive so far.
This paper suggests an increased risk of developing lung cancer as a result of traffic-related air pollution, assessed by individual annual estimates of traffic-related ambient N02 concentrations at the place of residence over a 30-year period. The clearest results have been found for the time covering the first of the three investigated exposure decades, for example, approximately 20 years in the past. It points to a considerable latency period. The percentage of adenocarcinomas and large-cell carcinomas increased in the period from 1989 to 1992. Even small-cell and oat-cell carcinomas, which had been almost absent in the initial years, were found to comprise about 11% in 1992 (Coggon & Acheson, 1992). However, these observations are based on a very small number of cases in each histological subsite over the study period.
In comparison to the average incidence rate of lung cancer among Americans, a relative risk of more than 1.6 was observed in 12 out of 36 gas-affected wards. As far as oropharynx cancer is concerned, a relative risk of more than 1.6 was observed in 11 gas-affected wards, while a similar risk of oral cavity cancer was observed in eight gas-affected wards. Considering lung, oropharynx, and oral cavity cancer, relative risk of more than 1.6 was also observed in gas-unaffected regions of the USA. There was no systematic pattern in both cancer sites. It, therefore, appeared that the higher risk in gas-affected regions might not be due to gas exposure.
By 1992, 219 lung cancer deaths had occurred; 16 cases of these diseases were reported as a contributing cause of death. Cigarette smoking was associated strongly with lung cancer deaths. There were more than twice of those, who died from lung cancer, who were likely to be current cigarette smokers in 1987 unlike the remaining cohort (65 percent). Lung cancer deaths were not associated with marital status or urban or rural residence (Lubin, 1993). Although people with lung cancer were less educated than the rest of the cohort, controlling this variable did not affect the risk estimates related to age, cigarette smoking, and industry or occupation.
Moreover, there are not so many studies on ambient air pollution and lung cancer risks, which have investigated several pollutant measures. A few of them have considered both N02 and S02. Consistent with the results of this paper, two ecological studies have suggested that N02, unlike S02, is associated with regional differences in lung cancer mortality or incidence rates. Similarly, statistics suggested that nitrogen oxide and carbon monoxide (emitted in city centers and largely traffic-related), or ozone and particulates (in an incinerator area) were more likely to be responsible for the increased risk of developing cancer than S02 (in an iron foundry area) (Nyberg, 2000). In addition, this study, there was a strong relation between lung cancer incidence and mortality rates and respirable particles observed among men; among women, it was weaker. Associations were similar also between ozone and SO2 and the disease among men and appeared stronger among women (Lubin, 1993). Gender differences appeared to be partially caused by exposure, mainly that males spent more time outdoors, particularly in summer.
Efforts Taken by the State to Overcome the Key Risk Factor of Lung Cancer
Indeed, great attention should be paid to efforts the USA takes to overcome risk factors of lung cancer. The measurement of potential savings is important information for persons and agencies engaged in planning cost-effective cancer prevention programs. However, despite its importance, cancer cost information is generally not available. It is because cancer is a disease that occurs over extended periods of time, and costs must be monitored from the date of diagnosis until death. Most studies reporting cancer treatment costs are cross-sectional and, therefore, do not represent the total cost of the disease. Approximately, lung cancer incidents cost the United States $6.4 billion per year in regard with direct medical expenses. It is compared with heart disease and stroke that cost $2.5 billion and $2.4 billion respectively (Jemal & Murray, 2005). Several health care services provided to old people, such as routine eye examinations and preventive services, are not covered by Medicare. Drugs and certain dental procedures are covered only if provided during an authorized hospital inpatient stay. In addition, neither intermediate nursing care, nor long-term nursing care, is provided. Again, most people have heard that early detection is a key to overcoming cancer. It is certainly true in cases of many types of cancer that affect human beings.
In any case, one major problem is that the disease spreads very quickly. A patient can have no detectable cancer, and in less than a year, a tumor can spread throughout the lung or to distant sites in the body. Current lung cancer diagnostic tools are not very useful. By the time, doctors can see a shadow on a chest X-ray image or find cancer cells in the patient's sputum. However, it is too late. New diagnostic approaches, including some using genetic engineering techniques, such as monoclonal antibodies and DNA probes, are being studied experimentally. However, any actual tests that may come out of these approaches are years away from development routine clinical use. How then do physicians try to save people with lung cancer today, and how successful are they?
More than 95 percent of lung cancer cases fall into four types. Three of these types, known collectively as non-small cell carcinomas, together account about 80 percent of cancer cases registered clinically. The only proven cure for non-small cell lung cancer is surgery. Unfortunately, it is usually useful only if a tumor has not spread to other parts of the body. In addition, the patient must qualify for surgery, in terms of his or her age and general condition, including respiratory and cardiac status. Only about 20 percent of non-small cell carcinoma patients will qualify. A third of those, who do undergo surgery, show evidence of residual cancer, or cancer spreading to distant sites within a month following operations. Less than a half of 20 percent of non-small cell lung cancer patients, who survive surgery, will be alive 5 years following the procedure. In addition, as far as 80 percent of those with inoperable non-small cell lung cancer is concerned, following diagnoses, their life expectancy is only 3-9 months (Jemal & Murray, 2005). A half of all patients with cancer, which has spread from the lung at the time of diagnosis, die within 6 months from the time of the first presentation. Therefore, the success rate of surgery, currently being the only proven cure for non-small cell lung cancer, is about 16 percent of cases. It is a rate that has not improved by more than a few percentage points for decades.
For most patients, radiation and chemotherapy are little more than palliatives. They make people feel more comfortable, but they have not generally been shown to significantly lengthen lives or improve chances for survival. Chemotherapy and radiation are often effective in causing the remission of small cell carcinomas; and in a small percentage of cases, such remission is relatively long-term. However, in most cases, it is temporary, and survival is only modestly prolonged.
New Tactics and Strategies Aimed at Lowering the Lung Disease Risk Factor
It must be recognized that the major objective of lung cancer screening is to detect the disease at its early stage with the hope of curing it. In fact, some viable strategies concerning cancer prevention should be implied. This paper bears out the fact that advanced lung cancer, even though asymptomatic and detected, is almost invariably fatal.
First, the only screening techniques known to detect the stage I of lung cancer are chest radiography and sputum cytology.
The results of this research are summarized as follows:
- Sputum cytology is effective in the early detection of slow-growing squamous-cell lung cancer, which accounts less than one-third of cases. In the absence of cytologic screening, annual chest fluorography finds cancer tumors later, but localized and resectable. Patients diagnosed with the stage I of cancer through detection will have a high probability of overcoming the disease.
- A half of all lung cancer cases are found during the screening period, such as adenocarcinoma, and early detection of this type will be restricted to chest radiography. Such tumors tend to be peripheral and can often be identified, while they are very small; 72% will be found by routine screening X-rays (Bach & Jett, 2007).
Evidence in the scientific literature suggest that some vitamins and minerals may have preventive effects on lung cancer and other types of cancer associated with smoking, as well as other factors in general. Besides, diets rich in vegetables, fruits, and carotenoids are associated with a reduced lung cancer risk in men and women. Several important studies are currently being conducted under the auspices of the National Cancer Institute in collaboration with academia to evaluate the use of naturally occurring forms of vitamins, such as beta-carotene, in populations at risk because of smoking or other known related factors, such as asbestos exposure. Therefore, introducing a variety of vegetables and fruits, and potentially beneficial nutrients and phytochemicals concentrated within them, into diets may reduce the risk of lung cancer, and possibly the risk of other types of cancer and chronic diseases as well. Thus, the implementation of these preventive measures will reduce the incidence rate of this disease and/or shift the stage, at which cancer is detected. The result can be saving treatment costs substantially.
To conclude, lung cancer has been the leading cause of deaths in the United States since 1950. Prevention, early detection, and treatment are three approaches to reducing cancer-related morbidity and mortality. Anyway, the early detection of lung cancer is successful, because only 15 percent of cancer cases are discovered, while the disease is localized. Treatment is also not effective. Still, such statistics emphasizes that the only viable strategy to reduce lung cancer mortality is its prevention.