Classification of Lung Cancer - Case Study Example

Running Head: Lung Cancer Introduction What is lung cancer? Lung cancer is a type of cancer that starts from the lungs and it is one of the most common and deadliest type of cancer in the world. Like other cancers, lung cancer results from an abnormality of cell growth in the lungs. Under normal circumstances, human bodies have a system that balances and check on the growth of cell for purposes of ensuring that cells divide only to produce new units when they are needed. It therefore follows that any form of disruption of this body system that checks and balances cell growth culminate into proliferation and uncontrolled division of cells that form a tumor in the long run (Fraumeni and Muir, 2004). Tumors are categorized into malignant or benign; the malignant tumors are what is referred to as cancer. Normally, benign tumors do not spread to other body parts and they can be easily removed when discovered. On the other hand, malignant tumors grow very aggressively thus, spreading to other parts of the body. This permits tumor cells to penetrate into the lymphatic or bloodstream system and other body sites. Metastasis is the process through which tumor cells spread, while the areas on which these tumor cells spread are referred to as metastases (Irvine et al., 2003). Normal airway and lung Lung Cancer Illustration Image Source: Medicine Net, Inc. Classification of lung cancer Lung cancer is one of the most deadly of all cancers since it spread very easily soon after the cancerous cells are formed. In fact, lung cancer is the most difficult category of cancer to be treated, thus, making it a very life threatening ailmement. It is very possible for lung cancer to metastasize to other organs of the body common among them being the brain, adrenal glands, bone, as well as liver. In classifying lung cancer, study shows that it can be broadly categorized into two main categories based on microscope appearance of the cancer. These two types of lung cancer are small cell lung cancer and non-small cell lung cancer. There is evidence to prove that, small cell lung cancer accounts for accounts for 20 per cent of lung cancer compared to Non-small cell lung cancer (NSCLC) which accounts for the remaining 80 per cent of lung cancers. It is worth noting that Non-small cell lung cancer (NSCLC) is further sub divided into four other categories each of which category having different alternative of treatment. These categories include: Adenocarcinoma, which is the most common type of lung cancer especially in non-smokers and women. This type of lung cancer develops in the lungs glands whose function is to produce mucus. Large cell undifferentiated carcinoma. Is another type of NSCLC that rapidly grow in the form of undifferentiated carcinomas large around the surface of the lungs or sometimes near the outer edge or around the surface of the lungs. The third type is the epidermoid carcinoma also referred to as the Squamous cell carcinoma. This is the most common type of lung cancer especially in especially amongst men. Under this type of NSCLC, the bronchial tubes lining develops squalors cell carcinoma which are cancerous in nature (Swerdlow et al., 2001). The fourth type of NSCLC is Bronchioalveolar carcinoma. Study shows that this category of lung cancer occurs when an unusual type of adenocarcinoma develops around the air sacs of the lungs to cause the cancer. In addition, SCLC (Small cell lung cancer) is generally exemplified by the presence of small cells which multiply very fast and eventually develop into large tumors which in turn spread all over the other body parts. Statistics tend to suggest that most if not all cases of Small cell lung cancers are caused in one way or another by smoking (Tyczynski et al., 2003). Discussion What causes cancer? Cancer develops in the lungs as a consequence of uncontrollable growth of cells, which do not die ultimately. As mentioned earlier, the body maintains a system through which the cell as the basic unit of life follows in terms of the process of growth, division, as well as death. The process through which the body cells die as they should is known as apoptosis. In the event that the process of apoptosis is obstructed, there is a danger that cancer may begin to develop since the cells do not die as they should (Mackenbach et al., 2004). Cancer cells unlike the normal cell do not go through the normal system of programmatic death but rather the cells continues to divide and grow, consequently, a mass of cells that are abnormal begin to grow and spread hysterically. The occurrence of lung cancer is therefore occasioned by the gene mutation of the lung cell making the cell incapable of committing suicide when necessary and also incapable of correcting damage in the DNA . The causes of mutations are quite many; nevertheless, the majority of lung cancer cases are triggered by inhaling substances that contain carcinogen. Carcinogens substances include substances such as compounds from car exhaust fumes, asbestos, arsenic, Tobacco, and radiation such as the sun, x-rays, and gamma. These substances have been highlighted as the major causes of DNA damaging, which in turn facilitate cancer development. As Janssen and Coebergh (2003) puts it, once human body is exposed to carcinogenic substances, there is formation of free radicals, which attempts to take away electrons from other body molecules. For this reasons the free radicals affects the ability of the cells to divide and function normally since the radical’s damage the cells completely. Statistics show that about 87 percent of all lung cancers are associated with either inhaling or smoking the carcinogens substances contained in the smoke of tobacco. Cells can also be damaged by exposure to second hand smoke and this can also lead to development of cancer (Ferlay et al., 2010). Scavenger cells in smokers alveolus Image Source: Medicine Net, Inc. Symptoms of lung cancer There are a number of symptoms associated with cancer and most of which are dependent on the size of the tumor, where is has spread as well as its location. It is worth noting that the symptoms of lung cancer may often take time before they become visible, often these symptoms are evident during the advanced stages of the disease. Most of these lung cancer symptoms affect the air passage as well as the chest and they may include inter alia; intense or Persistent coughing, Pain in the back from coughing or chest shoulder, Changes in color of the sputum (mucus that is coughed out from the lower part of the airways), Difficulty in swallowing and breathing, Hoarseness of the voice, having stridor (Harsh sounds while breathing), having Chronic pneumonia or bronchitis, Coughing up blood in the sputum, or blood (Doll and Hill, 2000). The spread of lung cancer cells may bring about symptoms that are related to other forms of ailments since more energy is used up by the body. Some of the other possible symptoms of lung cancer may include: Fever, General weakness, Fatigue, Bleeding and blood clots, unexplained weight loss, Pain in joints or bones, swelling in the neck or face, and Problems with memory and brain function (Lucchin, 2002). Treatment of lung cancer The treatment of lung cancer is highly dependent on several factors such as the stage at which the cancer has advanced type of cancer, health status of a person, additional individual traits, as well as the age of the person. Often patient receives a combination of palliative care and therapies since there are no particular cancer treatment that can be singled out. A patient of lung cancer may undergo one or a combination of the following treatment: chemotherapy, radiation, gene therapy, hormone therapy, immunotherapy, and surgery (Brennan and Bray, 2002). Prevalence of lung cancer Principally, lung cancer is a disease that is prevalent amongst the elderly. According to a study conducted by Harkness et al (2002) about 70 percent of the patients diagnosed with the ailment of lung cancer were people over the age of 65, on the other hand, only 30 per cent of lung cancer was reported among the persons who were under the age of 45 years. Study show that in Scotland the chances of a person surviving the killer disease are determined by the part of the country such a person lives (Borras et al., 2003). The report stated that there are more individuals from the most deprived areas of Scotland diagnosed with lung cancer than other parts of the country. The report further state that an individual from a place such as Clyde and Greater Glasgow has a higher possibility of developing lung cancer compared to a person who lives in an area such as Grampian. Trends and future projections The mortality statistics of lung cancer may be found described using geographical variations, age, deprivation, time trends, and ethnicity. In a study conducted by Ries et al (2008), there was an enormous impact of lung cancer on the mortality rate, which in total accounted for 6 per cent of all deaths as well as about 22 percent of all cancer deaths across UK. The study further indicated that in every 15 minutes one person dies of lung cancer in UK (Ries et al., 2008).   Quinn et al (2001) indicated that in UK lung cancer is the most common cause of death amongst women and men. From the study, lung cancer causes about 21 percent of all female deaths which is a fifth of all cancer deaths while it causes about 24 percent of all cancer deaths in men which is about a quarter of all the cancer deaths. Drawing an inference from the above statistical review one would then be right to conclude that in UK the number of male deaths related to lung cancer are more than those of their female counterparts. Considering age against lung cancer prevalence, there is evidence suggesting that more than three quarters of all the lung cancer patients in UK die at or above the age of 65 years, nevertheless, following the huge number of deaths caused by lung cancer in general, Subramanian and Govindan (2000) indicate that, lung cancer cost over 4,000 lives of persons below 60 years of age. Conclusion In the trends over time, all the way through the twentieth century the significance of lung cancer as a major cause of mortality has tremendously grown. Lung cancer was not very prevalent during the early 1990s and only caused less than 10 deaths in every 100,000 men every year. During the 1950s, however, the rates of deaths caused by lung cancer increased drastically, and this prompted a study that was undertaken in UK for purposes of establishing the link between lung cancer and tobacco smoking. Lung cancer death rates had raised to over 100 in every 100, 000 men by 1980. It is however worthy noting that the mortality rates of men in UK since early 1980s have constantly fallen. According to Franceschi and Bidoli (1999), the implication of the different patterns of death rates caused by lung cancer in women and men is a clear indication of the smoking behavior in men who unlike women started smoking earlier and heavily. In Scotland lung cancer mortality rates for men decreased progressively from early 1980s to 2008. The mortality rates decreased from about 119 to about 66 per every 100,000 men in Scotland. There is also evidence that indicate that between 1982 and 2008 female mortality rate caused by lung cancer amplified, this rates are feared to be further rising. Some experts even suggest that in future, female death rates for lung cancer are likely to increase slightly, while that of their male counterparts continues to fall. In terms of ethnicity, where country of birth is considered as a mode of ethnic group rough estimation, lung cancer in all ethnic groups is more prevalent in men than women. Nevertheless, the percentage of mortality rates caused by lung cancer show a discrepancy according to the country of birth. The lowest proportions of deaths were registered among the Pakistani born male while the highest death rates registered among the Scottish born men (Bray et al., 2004). Lung cancer results from an abnormality of cell growth in the lungs. It is the most difficult category of cancer to be treated, thus, making it a very life threatening ailment. It is very possible for lung cancer to metastasize to other organs of the body common among them being the brain, adrenal glands, bone, as well as liver. In classifying lung cancer, study shows that it can be broadly categorized into two main categories based on microscope appearance of the cancer. These two types of lung cancer are small cell lung cancer and non-small cell lung cancer (Didkowska et al., 2005). The symptoms of lung cancer may often take time before they become visible; often, these symptoms are evident during the advanced stages of the disease. These symptoms include: intense or Persistent coughing, Pain in the back from coughing or chest shoulder, Changes in color of the sputum among others. In treatment of cancer patient may undergo one or a combination of the following treatment: gene therapy, chemotherapy, radiation, hormone therapy, surgery, and immunotherapy. References  Borras, J, M, et al, 2003, ‘Lung cancer mortality in European regions (1955-1997)’. Annals of Oncology, 14: p. 159-161. Bray, F, et al, 2004, ‘Going up or coming down? The changing phases of the lung cancer epidemic from 1967 to 1999 in the 15 European Union countries.’ Euro J Cancer, 40(1):96-125  Brennan, P, and Bray, I, 2002, ‘Recent trends and future directions for lung cancer mortality in Europe.’ Br J Cancer, 87(1): p. 43-8. Didkowska, J, et al, 2005, ‘Lung cancer mortality at ages 35-43 in the European Union: ecological study of evolving tobacco epidemics.’ BMJ; 331 (7510):189-91 Doll, R, and Hill, A, 2000, ‘Smoking and carcinoma of the lung. Preliminary report.’ British Medical Journal, 739-48.  Ferlay, J, et al, 2010, ‘Estimates of the cancer incidence and mortality in Europe in 2008.’ European Journal of Cancer, 46, (4), 765-781 Ferlay, J, et al, 2004, Globocan 2002: Cancer Incidence, Mortality, and Prevalence. Worldwide Lyon: IARC Press. Fishbein, M, 2010, Smokers Lung Pathology Photo Essay. Accessed on 3/3/2012, from: http://www.medicinenet.com/smokers_lung_pathology_photo_essay/article.htm#tocb. Franceschi, S, and Bidoli, E, 1999, ‘The epidemiology of lung cancer.’ Ann Oncol, 10 (5) S3-6 Fraumeni, D, and Muir, J, 2004, Trends in Cancer Incidence and Mortality. In: Sidebottom Cancer Surveys. New York: Cold Spring Harbor Laboratory Press.  Harkness, F, et al, 2002, ‘Changing trends in incidence of lung cancer by histologic type in Scotland.’ Int J Cancer, 102(2): p. 179-83 Irvine, H, et al, 2003, ‘Asbestos and lung cancer in Glasgow and the west of Scotland.’ Bmj, 306(6891): p. 1503-6 Janssen, L, and Coebergh, J, 2003, ‘The changing epidemiology of lung cancer in Europe.’ Lung Cancer Journal. 41(3): p. 245-58 Lucchin, L, 2002, ‘Cancer Mortality in Europe, 1990-1994, and an Overview of Trends from 1955 to 1994.’ European Journal of Cancer, 35: p. 1477-1516. Mackenbach, J, et al, 2004, ‘Inequalities in lung cancer mortality by the educational level in 10 European populations.’ Eur J Cancer, 40(1):36-125  Quinn, M, et al, 2005, Cancer Atlas of the United Kingdom and Ireland 1991-2000 . London: Office for National Statistics press.  Ries, L, et al, 2003, ‘SEER Cancer Statistics Review, 1975-2000.’ National Cancer Institute, Bethesda, MD, 40(1):36-125 Subramanian, J, and Govindan, R, 2007, ‘Lung cancer in never smokers.’ J Clin Oncol; 25 (5):561-70 Swerdlow, A, et al, 2001, Cancer Incidence & Mortality in England & Wales: trends and risk factors. UK: Oxford University Press. Tyczynski, J, et al, 2003, ‘Lung cancer in Europe in 2000: epidemiology, prevention, and early detection.’ Lancet Oncol, 4(1):45-55 Read More