The Biology of Oral Cancer
Oral cancer, found in the oral cavity, can be detected early on. Cancers of the oral cavity are growths that appear on the lips, tongue, gingivae, palate, buccal mucosavestibule, salivary glands, and the floor of the mouth. Majority of these cancers are carcinomas, or tumors that cultivate from unrestrained growth of single cells or clones of cells that are found in the stratified squamous epithelium (Silverman 2001). Most of these cancers are of the squamous cell type, particularly squamous cell carninomas (SCCs). Carcinomas, on the other hand, are already developed tumors because of the non-prevented growth of cells or a group of cells (Silverman 2001).
Oral cancer is one of the most common cancers throughout the world. According to Johnson (1991), most of the cases are those of the squamous cell carcinomas, seen in both men and women in India, Bangladesh and Pakistan, reaching around 30 to 40 percent (Tanimoto 2000). Clearly, it is prevalent in developing countries with the lack of prevention and inattention to health care, it is among the leading causes of death. Moreover, according to the World Health Organization or WHO, most of the cases in these developing cases are among males (Tanimoto 2000)
According to the International Classification of Diseases, oral cancer also affects the pharynx, lips, tongue, salivary glands, gum, floor and other mouth areas. The oral cancer survival rate is one of the lowest in a five-year period (Wong 1996). This survival rate is again lowest as compared with other cancers including skin melanoma, and cancers of the breast, colon and kidney, among others. Oral cancer is cited clinically when there are color alterations or in the texture of the oral mucosa. A biopsy must be undergone once there is confirmed diagnosis of oral cancer (Chairman and Downer 1995).
Citing Sidransky (1995), the malignant cell becomes independent functionally as it continues to develop or mutate. It becomes independent of its environment made of normal oral keratinocytes (Wong 1996). The normal functions of the cell become those of tumor cells, increasing their capacity to propagate in nearby areas or metastasizing.
Previously believed to affect those of the older generation, it has been occurring in the younger age groups due to increasingly excessive use of products over a long period of time. These prompt these malignancies, along with tobacco and other related products.
While traces can be found in persons with a long history of smoking and alcoholism, there is a growing consciousness on oral cancer that is not necessarily associated with tobacco and alcohol abuse (Sciubba 2001). There are also studies that show that the use of smokeless tobacco is connected with risks in oral cancer albeit minimal. It was cited in the Comprehensive Smokeless Tobacco Education Act that smokeless tobacco is still harmful because of its carcinogenic effects (Rodu and Jansson 2004).
In the United States, oral cancers (along with pharyngeal cancers) comprise 3 percent of cancer cases in the US, and the forecast is that these cancers will give birth to 30,100 new cases and lead to 7,800 deaths (Silverman 2001). However, it has become apparent that there have been effects on the quality of life on survival cases, particularly the risk of developing cancers in the head or neck. Though with varying degrees, Silverman (2001) posits that the tendency is greater among smokers.
The cause of the tumor growth is not well comprehended, but pre-malignant states of the oral cancers have been noticed. The white and red spots inside the mouth are widely recognized as pre-malignant or pre cancerous. The tumor can possibly grow due to a series if accumulations of genetic alterations which is also observed in other types of cancers (Tanimoto et al 2000).
However, these cancers become untreatable when they are not diagnosed earlier, which is a poor enough reason given the early recognizable signs. Moreover, the oral cavity is very much examinable in that the appearance or growth of lesions or patches can be detected early on. The previous author also pointed out that when these lesions develop into cancerous ones by the time they are diagnosed, it can be difficult to attest success or effectiveness of the treatments (Tanimoto et al 2000).
The aggressive treatment required to improve cure rates for advanced lesions is associated with increased morbidity (Sciubba 2001). Further, Sciubba (2001) points out the disappointing fact that while oral cancers are easily examined about 90 seconds there have been few specialists who administer such examinations. Coupled by the lack of an massive awareness program, he states that the analysis on oral cancers for the past decades has not been made better.
Aside from the lack of knowledge, the late detection of such cases or the detection of advance cancerous lesions is attributed to the inaccessibility of reliable health care. Much effort should be geared towards enhancing the detection of precancerous or pre-malignant lesions, since herein lies the early prevention, as stressed by the previous author (Sciubba 2001).
Moreover, since the development of oral cancers can be detected at an early stage, the role of dental examinations is critical. The history of dental visits can very much form an integral part of detection. Thus, the dentist must take into account that risks are posed by patients and that they must act accordingly in these phases. Thus, by having a clear account of a patients oral history through examinations, the dentist can increase the likelihood of prevention (Sciubba 2001).
The same author argues that if an analysis of an advanced and much serious case is only later established, a less effective result is expected. Specialists or practitioners can largely affect the outcome and the patients quality of life when oral mucosal alterations are confronted representing SCCs in patients.
Risk Factors
Oral cancers develop due to certain risk factors that are generally believed to be a cause determinant. As already mentioned, excessive tobacco use and its related products and alcohol consumption are primary of these. In the United States, these factors are responsible for 75 percent of the cases. The doctor-researcher also names the use of marijuana as potentially harmful, as well as viruses like the human papillomavirus (HPV). However, a healthy diet with a considerable amount of fruits and vegetables is seen to decrease the aforementioned risk factors that develop oral cancers (Silverman 2001).
The rising role of the HPV in oral cancers has been observed in India. In a study, there has been 20 to 50 percent detection rate of HPV in oral carcinomas and thus the high positive rate is acknowledged to be a factor in the development of tumors in the head and neck (N. M. Chocolatewala and Chaturvedi 2009).
Oral cancers also tend to develop with age. There is a higher risk factor for those who are aged 45 years and above. The professorresearcher explains that such incidents are correlated with age because cellular biological alterations are a result of exposure to external harmful elements and pollutants, viruses, bad nutrition, and even unwanted elements in food products. As mentioned previously, bad habits which include heavy smoking and alcoholism are risk factors. Recently however, there are trends which show emerging cases in younger age groups, mostly young adults from 20 to 30 years of age, not necessarily related to the risk factors of tobacco and alcohol use (Silverman 2001).
In the results given by the National Cancer Institutes Surveillance, Epidemiology, and Ends Results (SEER), oral cancers have been noted recently in the time period from 1994 to 1998. Between this time, men are more likely hit than women, while in the race aspect, Blacks register higher incidence than whites. In the said study period, it has also been found that most of the cases are found in the tongue. Citing his previous study, Silverman (2001) comparing national data between the years 1973 and 1984 with data between the period of 1985 and 1996, shows that there is an increase in oral cancers that are found in the tongue (Silverman 2001).
Data coming from the SEER showed that there is a higher mortality rate in men than women in the US due to the said cancer. It was also found that survival rates for cancers found on the base of the tongue are low compared to that which are found in the visible tongue portion. This h is easily explained by the fact that said carcinomas are less or later diagnosed. Further, the low occurrence of cancers in the gingival and alveolar areas points out that there is no relation between those who wear dentures and development of malignant cancer cells (Silverman 2001).
Race and ethnicity are also risk factors. Genetic configurations and predispositions, even socio-economic factors, such as accessibility to quality medical care and lack of public awareness are contributory. The oral cavity is the fourth most cancer-prone area among black men in the US. The study which also covers various states in the US, suggests that the oral cavity is still the most common place of cancers, and also in black men. In California for instance, following blacks are non-Hispanic, Asians, and Hispanics, which are similar to national incidence rates and mortality rates (Silverman 2001).
Oral cancer has also been on the rise in the United Kingdom, at 25 percent in the past ten years according to an article in Health Education (n.d.). Again, the main culprits have been our usual suspects tobacco from smoking and alcohol abuse. However, in the UK, alcoholism is much more prevalent than smoking. The same article pointed out lack of public awareness, as oral cancers are not much publicized or tackled, despite its being a silent killer. In fact, there are more deaths that are caused by oral cancers than cervical or even testicular cancers added up.
In a research paper detailing the salient risk factors, Sciubba (2001) identifies tobacco use, alcohol consumption, diet and lifestyle. The research solidifies what have been previously explained on oral cancers risk factors zeroing in on these four culprits. The effects of excessive smoking and tobacco use have been common knowledge. Because of its potential impact and direct contribution to the development of oral cancers, the information should be known at the very start particularly in dental examinations. The use of tobacco is preponderant in other countries outside the United States particularly developing ones. Use usually refers to such practices as chewing betel leaf, tobacco and similar products, though smoking tobacco is still believed to be most harmful because of its many complications not just orally. Further, there has been a strong connection between the growth of pre-malignant oral cancers in the form of erythroplakia and tobacco chewing coupled with alcohol consumption (Sciubba 2001).
The same professor-researcher also links the strong relation of alcoholic consumption to the development of oral cancer, particularly with the combination of tobacco use or smoking. There is what is called a synergisticeffect with these two risk factors that trigger oral cancer development. There is believed to be a chemical alteration of elements both found in the said materials that complicate or trigger risk of oral cancer (Sciubba 2001).
Because there is increasing awareness on having a healthy lifestyle, diet is also considered to be influential in the development of oral cancers or even in its pre-malignant stage. However, if a diet which contains natural carotenoid compounds and vitamins A, C and E is maintained this can offer protection to the development of cancer (Sciubba 2001). In relation to diet, lifestyle is also integral in the determination of the entire risk factor in the development of oral cancers. Lifestyle is strongly linked to the usage of such prohibited substances that are risk factors of oral cancer, including tobacco and alcohol. Doctors would refer to the patients history or lifestyle to determine such risk factors that are prevalent. Naturally, in these examinations, the detection of contributory risk factors would somehow abate the development of oral cancers (Sciubba 2001).
Dental Problems as Early Risk Factors
At the onset, one of the very apparent triggers of the development of oral cancers is poor nutritional health and bad diet. Evidently, there is a relationship with our eating habits as well as our oral health. What we consume may also pose a risk (__, Nutrition and Food Science, n.d.).
In a report from the British Nutrition Foundation on Oral Health, participants of a conference they conducted assessed the relationships of diet and dental health in various age groups from children and older people with tooth defects including oral cancers (__, Nutrition and Food Science, n.d.).
As Edgar (n.d.) in the aforementioned conference paper stated, tooth cavities is a result of the interaction of three factors susceptible tooth tissues, oral bacteria in the form of dental plaque and dietary intake of fermentable carbohydrate, which are sugars for a certain period of time. Cavities are formed because of the conversion of acid by bacteria, thus, the proponent recommends the restriction of sugar intake. Further, such should be consumed at meal times and not in between meals, because these remain stagnant (__, Nutrition and Food Science, n.d.).
In a study in the UK, dental problems are prevalent among individuals over 65 years. Further, as cited by one professor from the University of Newcastle, surveys conducted nationwide in the years 1968, 1978 and 1988 reveal a slowdown in the number of people without natural teeth as another professor Walls said in the same conference paper report (n.d.). Moreover, this is very much the case when there are fewer dental visits. As pointed out earlier, detection of pre-malignant or early signs of cancers which can be brought about by these dental defects can be traced in the early examinations by the doctor or dentist.
If detected on an early stage, majority of around 75 percent of oral cancers can be avoided, which is an idea that the article also supported. Thus if there is a lifestyle change, if a person lessens or even avoids excessive drinking and smoking for over a long period of time, oral cancer cases can also be reduced drastically. Public awareness may be addressed by having effective, tangible materials coming from health practitioners themselves since they have first-hand encounters with patients (Silverman 2001).
Cost-Effective Screening for Oral Cancers
A study was conducted regarding the cost-effectiveness of oral cancer screening programs, using a decision analysis model. Data were sourced from two hospitals providing information on the costs required. Hypothetical screening programs were conducted from among a number of primary care settings and participants with a population of over 40 years (Speight 2006). The study points out that opportunistic screening for oral cancer may be cost effective. In addition, it recommends that this be done by general dental practitioners that have already gained expertise in mouth examinations, which is a practical approach (Speight 2006).
Speight (2006) further notes that the screening targets those within 40 to 60 years old for effectiveness. However, there is also uncertainty especially on the rate of malignant development and disease progression. Thus, studies that address or are geared towards determining malignant development as well as the progression rate of oral cancers are encouraged. However, a planned and controlled trial may be beneficial because the wait and see attitude is not highly encouraged, thus before arriving at a decision, a relevant data gathered (Speight et al 2006).
Molecular Biology
There is a poor forecast for patients who have oral malignancies because of the five-year survival rate (Shetty 2003). Further, the possibility of recurrences can become a hindrance to a progressive treatment for the development of oral cancers. Science, particularly through molecular epidemiology, is expected to devise an approach for prevention, moreover the avoidance of pre-cancerous lesions, and is expected to yield surgical techniques and forecasting.
Carcinogenesis is a difficult, multi-layered process wherein genetic activities within a cell are altered whether quantitatively or qualitatively (Wong, Todd, Tsuji and Donoff 1996). This approach is being looked into because the dependence on genetic basis of cancer is well-known. The signal transduction pathways of cells regulate the oral keratinocyte biology (Wong et al 1996).
The author also stressed the genetic aspects of oral cancer transformation as the result of gene alteration or intervention, and that this change may course through different genetic pathways. Eventually, the process can lead to a better understanding of the disease process itself. As suggested by Knudson and Nowell, carcinomas develop because of the buildup of many genetic activities that affect a cell, which may be a form of mutation or alterations (Shetty 2003). As the researchers pointed out, cancer results from a buildup of the changes in these cellular pathways, which may occur at any level of the pathway. Citing the abovementioned authors, up to six (6) mutations are needed to change a normal cell to become a malignant cell (Wong et al 1996). The researchers note that research on oral cancer pales in comparison to other cancer researches. Efforts should be aimed at enhancing diagnosis of pre-malignant epithelium and that the area of research activities targeted at lessening the occurrence and heightening the early diagnosis and cure of oral cancer covers basic science laboratory research to human clinical trials (Wong et al 1996).
Molecular biology analysis, as pointed out in previous paragraph on this section, is an important part of examination as well as other genetic technologies and techniques. Further, the mentioned researchers strongly recommend a cancer research program that incorporates the varied modes of technology in investigation but are somehow similarly relevant. Further, they suggest that it is vital to form a collaboration of scientists and specialists on this field towards the same aim of investigating further oral cancer research (Wong et al 1996).
Using molecular biology as an approach will amplify the likelihood of detecting high-risk lesions, particularly in the scientific field of molecular epidemiology. Second primary tumors, classified into those that are detected simultaneously (synchronous) and those that are found out only after a certain duration of time (metachronous), are expounded based on genetics (Shetty 2003).
Studies also point out inherent and adaptive immune effectors in tumor elimination in which mounting successful anti-tumor responses are recognized while on the other hand, much evidence shows that immune responses should hold back or diminish transformed cells in many cancer patients, including oral cancer (Jewett, Head and Cacalano 2006).
As we understand more anti-tumor responses and cancers, we recognize the interaction between immune effectors and tumor cells. In immunoediting, we learn that these immune effectors shape tumor cells, select cancers with lessened immunogenicity and enhanced capacity to actively induce immunosuppression (Jewett, Head and Cacalano 2006). A multi-disciplinary approach in oral cancer management has been noted especially with advances in molecular biology. Some of the emerging challenges include enhancing rates of therapy, lessening morbidity of treatment and the use of molecular indicators to foresee tumor behavior thus appropriating accurate treatment (Ord and Blanchaert 2001).
DNA Hybridization
The DNA hybridization array is used to analyze the gene expression in biologic systems (Todd Wong 2002). This technology been used to study cellular activities particularly in physiologic responses to environmental factors in an intact organism. Since DNA is being analyzed, nucleic acids from samples are examined. Further, the researcher states that this approach has been implemented in the research of cancer for improved comprehension, as well as better diagnosis and cure of malignancies in humans (Todd Wong 2002).
With the relevance of this technology, it is now being used in cancer therapeutic research through these two strategies biomarker identification and drug discovery. As mentioned, this holds a promising result in the case for improved diagnoses and even in the treatment of cancer, particularly the detection of pre-malignant formations of lesions and identification of the malignancy. Further, the DNA hybridization array technology will see its importance in the area of drug development because it identifies targets in preventing the development of oral cancers (Todd and Wong 2002).
Todd and Wong (2002), explained that DNA hybridization arrays were used to identify gene clusters that would predict the responsiveness of oral cancer to radiation and pointed out that in the aforementioned study the radiation resistance has decreased tumor size with continuous exposure treatment for six (6) weeks. Radiation responsiveness was also predicted. Further, the researchers planned to enhance the gene expression profile to establish a more correct means of patient identification with non-responsive oral cancers.
Health and Nutrition
The use of vitamin A analogs which include beta-carotene, has been studied closely particularly in the progress of examinations being carried out using this approach that could considerably contribute to the avoidance of recurrence of new primary oral tumors. Similar protective properties of other food elements are also being looked into (Chairman and Downer 1995).
Thus, the researchers also urged changes in lifestyle particularly on those risk factors, through promoting healthy lifestyle and its vital importance in the prevention of oral cancer and even in its pre-malignant phase. However, the authors also point out the cost-benefits of interventions (Chairman and Downer 1995).
Bionutrition emphasizes the importance and relationships of diet, nutrient consumption, genetics, and surrounding environment, taking into account the functions of these nutrients and other food elements in a healthy lifestyle and in disease prevention (Enwonwu and Meeks 1995). The study also supports that the common culprits in increasing the risk of oral cancers, excessive tobacco use and alcohol consumption. Around 80 to 90 percent of human cancers are environmentally-triggered or caused by factors in the environment, and changes in diet increase the likelihood of reducing deaths by around 35 percent.
In a research review by Chairman and Downer (1995), they mentioned a study conducted concerning the mass screening of oral cancer and pre-cancer in Japan, particularly in Aichi Prefecture in Tokoname City. The procedures for the study are intensive which require primary preventive education to targeted population, referring particularly to mails that invite target participants for an oral examination. The patients who underwent examinations were also recommended for diagnosis for confirmation of patients who have the disease. These procedures were stringent since these were administered through the supervision of the World Health Organization (WHO).
The said study stressed on the importance of health promotions, targeting populations and ensuring their compliance, and establishing screening standards. The study also ensured that specialists administer the procedures using advanced technology, and further, controlled trials. The study also showed that the lessening of tobacco and alcohol use contribute to the slowdown of oral cancer cases. Moreover, early diagnoses reduce the likelihood of oral cancers and make it preventable (Chairman and Downer 1995).
In the same research review, the focus of prevention of oral cancer at the primary level is the prohibition of use of tobacco and alcohol, while recognizing white and red changes in the oral cavity as oral cancer precedents are aimed as a secondary prevention. There is good prognosis if oral cancer is cured at its early stage. Since the first clinical signals of oral cancer are red and white changes in the oral cavity, earlier diagnosis is strongly recommended. The authors also did not recommend exfoliative procedures because of likelihood for negative results.
However, for especially high-risk cases, a cold-knife surgery or laser surgery is preferred. If results reveal a presence of distinct epithelial dysplasia, treatment is strongly urged (Chairman and Downer 1995). Further, they also recommended a systematic dispensation of substances like beta-carotene and isoretinoin. Patients must continue with follow-up examinations and treatment because of the high risk of developing second and third primaries in respiratory and upper alimentary tracts.
Despite its traces being recognizable, as it can be found immediately in the oral cavity, signs have been neglected this making oral cancer a serious and fatal disease if not prevented. The appearance of red and white lesions or patches can already be a case of oral cancer. It can affect the patients quality of life because of the development of further complications if malignancies remain untreated. Treatment in these instances may already be costly. Prevention of the cancer at its pre-malignant phase should be prioritized. These are often detected during dental visits and oral examinations, thus, the role of the dentist is also crucial.
There is also greater need for public awareness. An information mechanism that would also target patients and those already with positive results is highly encouraged. Since the main risk factors include excessive alcohol and tobacco use (smoking and smokeless tobacco), health care professionals must recognize the importance of a healthy lifestyle, as well as a good diet, especially since nutrients can also help lessen oral cancer probability, e.g. beta-carotene.
Oral cancer is a serious disease considering there is a five-year survival rate among researches and studies undergone on the disease. Dentists and health care practitioners thus have a crucial role in ensuring that patients have regular and comprehensive examinations. Further, scientific research have shown the importance of molecular biology or epidemiology in advancing better treatment and curative measures of oral cancer, thus encouraging further engagements in research.
Oral cancer is one of the most common cancers throughout the world. According to Johnson (1991), most of the cases are those of the squamous cell carcinomas, seen in both men and women in India, Bangladesh and Pakistan, reaching around 30 to 40 percent (Tanimoto 2000). Clearly, it is prevalent in developing countries with the lack of prevention and inattention to health care, it is among the leading causes of death. Moreover, according to the World Health Organization or WHO, most of the cases in these developing cases are among males (Tanimoto 2000)
According to the International Classification of Diseases, oral cancer also affects the pharynx, lips, tongue, salivary glands, gum, floor and other mouth areas. The oral cancer survival rate is one of the lowest in a five-year period (Wong 1996). This survival rate is again lowest as compared with other cancers including skin melanoma, and cancers of the breast, colon and kidney, among others. Oral cancer is cited clinically when there are color alterations or in the texture of the oral mucosa. A biopsy must be undergone once there is confirmed diagnosis of oral cancer (Chairman and Downer 1995).
Citing Sidransky (1995), the malignant cell becomes independent functionally as it continues to develop or mutate. It becomes independent of its environment made of normal oral keratinocytes (Wong 1996). The normal functions of the cell become those of tumor cells, increasing their capacity to propagate in nearby areas or metastasizing.
Previously believed to affect those of the older generation, it has been occurring in the younger age groups due to increasingly excessive use of products over a long period of time. These prompt these malignancies, along with tobacco and other related products.
While traces can be found in persons with a long history of smoking and alcoholism, there is a growing consciousness on oral cancer that is not necessarily associated with tobacco and alcohol abuse (Sciubba 2001). There are also studies that show that the use of smokeless tobacco is connected with risks in oral cancer albeit minimal. It was cited in the Comprehensive Smokeless Tobacco Education Act that smokeless tobacco is still harmful because of its carcinogenic effects (Rodu and Jansson 2004).
In the United States, oral cancers (along with pharyngeal cancers) comprise 3 percent of cancer cases in the US, and the forecast is that these cancers will give birth to 30,100 new cases and lead to 7,800 deaths (Silverman 2001). However, it has become apparent that there have been effects on the quality of life on survival cases, particularly the risk of developing cancers in the head or neck. Though with varying degrees, Silverman (2001) posits that the tendency is greater among smokers.
The cause of the tumor growth is not well comprehended, but pre-malignant states of the oral cancers have been noticed. The white and red spots inside the mouth are widely recognized as pre-malignant or pre cancerous. The tumor can possibly grow due to a series if accumulations of genetic alterations which is also observed in other types of cancers (Tanimoto et al 2000).
However, these cancers become untreatable when they are not diagnosed earlier, which is a poor enough reason given the early recognizable signs. Moreover, the oral cavity is very much examinable in that the appearance or growth of lesions or patches can be detected early on. The previous author also pointed out that when these lesions develop into cancerous ones by the time they are diagnosed, it can be difficult to attest success or effectiveness of the treatments (Tanimoto et al 2000).
The aggressive treatment required to improve cure rates for advanced lesions is associated with increased morbidity (Sciubba 2001). Further, Sciubba (2001) points out the disappointing fact that while oral cancers are easily examined about 90 seconds there have been few specialists who administer such examinations. Coupled by the lack of an massive awareness program, he states that the analysis on oral cancers for the past decades has not been made better.
Aside from the lack of knowledge, the late detection of such cases or the detection of advance cancerous lesions is attributed to the inaccessibility of reliable health care. Much effort should be geared towards enhancing the detection of precancerous or pre-malignant lesions, since herein lies the early prevention, as stressed by the previous author (Sciubba 2001).
Moreover, since the development of oral cancers can be detected at an early stage, the role of dental examinations is critical. The history of dental visits can very much form an integral part of detection. Thus, the dentist must take into account that risks are posed by patients and that they must act accordingly in these phases. Thus, by having a clear account of a patients oral history through examinations, the dentist can increase the likelihood of prevention (Sciubba 2001).
The same author argues that if an analysis of an advanced and much serious case is only later established, a less effective result is expected. Specialists or practitioners can largely affect the outcome and the patients quality of life when oral mucosal alterations are confronted representing SCCs in patients.
Risk Factors
Oral cancers develop due to certain risk factors that are generally believed to be a cause determinant. As already mentioned, excessive tobacco use and its related products and alcohol consumption are primary of these. In the United States, these factors are responsible for 75 percent of the cases. The doctor-researcher also names the use of marijuana as potentially harmful, as well as viruses like the human papillomavirus (HPV). However, a healthy diet with a considerable amount of fruits and vegetables is seen to decrease the aforementioned risk factors that develop oral cancers (Silverman 2001).
The rising role of the HPV in oral cancers has been observed in India. In a study, there has been 20 to 50 percent detection rate of HPV in oral carcinomas and thus the high positive rate is acknowledged to be a factor in the development of tumors in the head and neck (N. M. Chocolatewala and Chaturvedi 2009).
Oral cancers also tend to develop with age. There is a higher risk factor for those who are aged 45 years and above. The professorresearcher explains that such incidents are correlated with age because cellular biological alterations are a result of exposure to external harmful elements and pollutants, viruses, bad nutrition, and even unwanted elements in food products. As mentioned previously, bad habits which include heavy smoking and alcoholism are risk factors. Recently however, there are trends which show emerging cases in younger age groups, mostly young adults from 20 to 30 years of age, not necessarily related to the risk factors of tobacco and alcohol use (Silverman 2001).
In the results given by the National Cancer Institutes Surveillance, Epidemiology, and Ends Results (SEER), oral cancers have been noted recently in the time period from 1994 to 1998. Between this time, men are more likely hit than women, while in the race aspect, Blacks register higher incidence than whites. In the said study period, it has also been found that most of the cases are found in the tongue. Citing his previous study, Silverman (2001) comparing national data between the years 1973 and 1984 with data between the period of 1985 and 1996, shows that there is an increase in oral cancers that are found in the tongue (Silverman 2001).
Data coming from the SEER showed that there is a higher mortality rate in men than women in the US due to the said cancer. It was also found that survival rates for cancers found on the base of the tongue are low compared to that which are found in the visible tongue portion. This h is easily explained by the fact that said carcinomas are less or later diagnosed. Further, the low occurrence of cancers in the gingival and alveolar areas points out that there is no relation between those who wear dentures and development of malignant cancer cells (Silverman 2001).
Race and ethnicity are also risk factors. Genetic configurations and predispositions, even socio-economic factors, such as accessibility to quality medical care and lack of public awareness are contributory. The oral cavity is the fourth most cancer-prone area among black men in the US. The study which also covers various states in the US, suggests that the oral cavity is still the most common place of cancers, and also in black men. In California for instance, following blacks are non-Hispanic, Asians, and Hispanics, which are similar to national incidence rates and mortality rates (Silverman 2001).
Oral cancer has also been on the rise in the United Kingdom, at 25 percent in the past ten years according to an article in Health Education (n.d.). Again, the main culprits have been our usual suspects tobacco from smoking and alcohol abuse. However, in the UK, alcoholism is much more prevalent than smoking. The same article pointed out lack of public awareness, as oral cancers are not much publicized or tackled, despite its being a silent killer. In fact, there are more deaths that are caused by oral cancers than cervical or even testicular cancers added up.
In a research paper detailing the salient risk factors, Sciubba (2001) identifies tobacco use, alcohol consumption, diet and lifestyle. The research solidifies what have been previously explained on oral cancers risk factors zeroing in on these four culprits. The effects of excessive smoking and tobacco use have been common knowledge. Because of its potential impact and direct contribution to the development of oral cancers, the information should be known at the very start particularly in dental examinations. The use of tobacco is preponderant in other countries outside the United States particularly developing ones. Use usually refers to such practices as chewing betel leaf, tobacco and similar products, though smoking tobacco is still believed to be most harmful because of its many complications not just orally. Further, there has been a strong connection between the growth of pre-malignant oral cancers in the form of erythroplakia and tobacco chewing coupled with alcohol consumption (Sciubba 2001).
The same professor-researcher also links the strong relation of alcoholic consumption to the development of oral cancer, particularly with the combination of tobacco use or smoking. There is what is called a synergisticeffect with these two risk factors that trigger oral cancer development. There is believed to be a chemical alteration of elements both found in the said materials that complicate or trigger risk of oral cancer (Sciubba 2001).
Because there is increasing awareness on having a healthy lifestyle, diet is also considered to be influential in the development of oral cancers or even in its pre-malignant stage. However, if a diet which contains natural carotenoid compounds and vitamins A, C and E is maintained this can offer protection to the development of cancer (Sciubba 2001). In relation to diet, lifestyle is also integral in the determination of the entire risk factor in the development of oral cancers. Lifestyle is strongly linked to the usage of such prohibited substances that are risk factors of oral cancer, including tobacco and alcohol. Doctors would refer to the patients history or lifestyle to determine such risk factors that are prevalent. Naturally, in these examinations, the detection of contributory risk factors would somehow abate the development of oral cancers (Sciubba 2001).
Dental Problems as Early Risk Factors
At the onset, one of the very apparent triggers of the development of oral cancers is poor nutritional health and bad diet. Evidently, there is a relationship with our eating habits as well as our oral health. What we consume may also pose a risk (__, Nutrition and Food Science, n.d.).
In a report from the British Nutrition Foundation on Oral Health, participants of a conference they conducted assessed the relationships of diet and dental health in various age groups from children and older people with tooth defects including oral cancers (__, Nutrition and Food Science, n.d.).
As Edgar (n.d.) in the aforementioned conference paper stated, tooth cavities is a result of the interaction of three factors susceptible tooth tissues, oral bacteria in the form of dental plaque and dietary intake of fermentable carbohydrate, which are sugars for a certain period of time. Cavities are formed because of the conversion of acid by bacteria, thus, the proponent recommends the restriction of sugar intake. Further, such should be consumed at meal times and not in between meals, because these remain stagnant (__, Nutrition and Food Science, n.d.).
In a study in the UK, dental problems are prevalent among individuals over 65 years. Further, as cited by one professor from the University of Newcastle, surveys conducted nationwide in the years 1968, 1978 and 1988 reveal a slowdown in the number of people without natural teeth as another professor Walls said in the same conference paper report (n.d.). Moreover, this is very much the case when there are fewer dental visits. As pointed out earlier, detection of pre-malignant or early signs of cancers which can be brought about by these dental defects can be traced in the early examinations by the doctor or dentist.
If detected on an early stage, majority of around 75 percent of oral cancers can be avoided, which is an idea that the article also supported. Thus if there is a lifestyle change, if a person lessens or even avoids excessive drinking and smoking for over a long period of time, oral cancer cases can also be reduced drastically. Public awareness may be addressed by having effective, tangible materials coming from health practitioners themselves since they have first-hand encounters with patients (Silverman 2001).
Cost-Effective Screening for Oral Cancers
A study was conducted regarding the cost-effectiveness of oral cancer screening programs, using a decision analysis model. Data were sourced from two hospitals providing information on the costs required. Hypothetical screening programs were conducted from among a number of primary care settings and participants with a population of over 40 years (Speight 2006). The study points out that opportunistic screening for oral cancer may be cost effective. In addition, it recommends that this be done by general dental practitioners that have already gained expertise in mouth examinations, which is a practical approach (Speight 2006).
Speight (2006) further notes that the screening targets those within 40 to 60 years old for effectiveness. However, there is also uncertainty especially on the rate of malignant development and disease progression. Thus, studies that address or are geared towards determining malignant development as well as the progression rate of oral cancers are encouraged. However, a planned and controlled trial may be beneficial because the wait and see attitude is not highly encouraged, thus before arriving at a decision, a relevant data gathered (Speight et al 2006).
Molecular Biology
There is a poor forecast for patients who have oral malignancies because of the five-year survival rate (Shetty 2003). Further, the possibility of recurrences can become a hindrance to a progressive treatment for the development of oral cancers. Science, particularly through molecular epidemiology, is expected to devise an approach for prevention, moreover the avoidance of pre-cancerous lesions, and is expected to yield surgical techniques and forecasting.
Carcinogenesis is a difficult, multi-layered process wherein genetic activities within a cell are altered whether quantitatively or qualitatively (Wong, Todd, Tsuji and Donoff 1996). This approach is being looked into because the dependence on genetic basis of cancer is well-known. The signal transduction pathways of cells regulate the oral keratinocyte biology (Wong et al 1996).
The author also stressed the genetic aspects of oral cancer transformation as the result of gene alteration or intervention, and that this change may course through different genetic pathways. Eventually, the process can lead to a better understanding of the disease process itself. As suggested by Knudson and Nowell, carcinomas develop because of the buildup of many genetic activities that affect a cell, which may be a form of mutation or alterations (Shetty 2003). As the researchers pointed out, cancer results from a buildup of the changes in these cellular pathways, which may occur at any level of the pathway. Citing the abovementioned authors, up to six (6) mutations are needed to change a normal cell to become a malignant cell (Wong et al 1996). The researchers note that research on oral cancer pales in comparison to other cancer researches. Efforts should be aimed at enhancing diagnosis of pre-malignant epithelium and that the area of research activities targeted at lessening the occurrence and heightening the early diagnosis and cure of oral cancer covers basic science laboratory research to human clinical trials (Wong et al 1996).
Molecular biology analysis, as pointed out in previous paragraph on this section, is an important part of examination as well as other genetic technologies and techniques. Further, the mentioned researchers strongly recommend a cancer research program that incorporates the varied modes of technology in investigation but are somehow similarly relevant. Further, they suggest that it is vital to form a collaboration of scientists and specialists on this field towards the same aim of investigating further oral cancer research (Wong et al 1996).
Using molecular biology as an approach will amplify the likelihood of detecting high-risk lesions, particularly in the scientific field of molecular epidemiology. Second primary tumors, classified into those that are detected simultaneously (synchronous) and those that are found out only after a certain duration of time (metachronous), are expounded based on genetics (Shetty 2003).
Studies also point out inherent and adaptive immune effectors in tumor elimination in which mounting successful anti-tumor responses are recognized while on the other hand, much evidence shows that immune responses should hold back or diminish transformed cells in many cancer patients, including oral cancer (Jewett, Head and Cacalano 2006).
As we understand more anti-tumor responses and cancers, we recognize the interaction between immune effectors and tumor cells. In immunoediting, we learn that these immune effectors shape tumor cells, select cancers with lessened immunogenicity and enhanced capacity to actively induce immunosuppression (Jewett, Head and Cacalano 2006). A multi-disciplinary approach in oral cancer management has been noted especially with advances in molecular biology. Some of the emerging challenges include enhancing rates of therapy, lessening morbidity of treatment and the use of molecular indicators to foresee tumor behavior thus appropriating accurate treatment (Ord and Blanchaert 2001).
DNA Hybridization
The DNA hybridization array is used to analyze the gene expression in biologic systems (Todd Wong 2002). This technology been used to study cellular activities particularly in physiologic responses to environmental factors in an intact organism. Since DNA is being analyzed, nucleic acids from samples are examined. Further, the researcher states that this approach has been implemented in the research of cancer for improved comprehension, as well as better diagnosis and cure of malignancies in humans (Todd Wong 2002).
With the relevance of this technology, it is now being used in cancer therapeutic research through these two strategies biomarker identification and drug discovery. As mentioned, this holds a promising result in the case for improved diagnoses and even in the treatment of cancer, particularly the detection of pre-malignant formations of lesions and identification of the malignancy. Further, the DNA hybridization array technology will see its importance in the area of drug development because it identifies targets in preventing the development of oral cancers (Todd and Wong 2002).
Todd and Wong (2002), explained that DNA hybridization arrays were used to identify gene clusters that would predict the responsiveness of oral cancer to radiation and pointed out that in the aforementioned study the radiation resistance has decreased tumor size with continuous exposure treatment for six (6) weeks. Radiation responsiveness was also predicted. Further, the researchers planned to enhance the gene expression profile to establish a more correct means of patient identification with non-responsive oral cancers.
Health and Nutrition
The use of vitamin A analogs which include beta-carotene, has been studied closely particularly in the progress of examinations being carried out using this approach that could considerably contribute to the avoidance of recurrence of new primary oral tumors. Similar protective properties of other food elements are also being looked into (Chairman and Downer 1995).
Thus, the researchers also urged changes in lifestyle particularly on those risk factors, through promoting healthy lifestyle and its vital importance in the prevention of oral cancer and even in its pre-malignant phase. However, the authors also point out the cost-benefits of interventions (Chairman and Downer 1995).
Bionutrition emphasizes the importance and relationships of diet, nutrient consumption, genetics, and surrounding environment, taking into account the functions of these nutrients and other food elements in a healthy lifestyle and in disease prevention (Enwonwu and Meeks 1995). The study also supports that the common culprits in increasing the risk of oral cancers, excessive tobacco use and alcohol consumption. Around 80 to 90 percent of human cancers are environmentally-triggered or caused by factors in the environment, and changes in diet increase the likelihood of reducing deaths by around 35 percent.
In a research review by Chairman and Downer (1995), they mentioned a study conducted concerning the mass screening of oral cancer and pre-cancer in Japan, particularly in Aichi Prefecture in Tokoname City. The procedures for the study are intensive which require primary preventive education to targeted population, referring particularly to mails that invite target participants for an oral examination. The patients who underwent examinations were also recommended for diagnosis for confirmation of patients who have the disease. These procedures were stringent since these were administered through the supervision of the World Health Organization (WHO).
The said study stressed on the importance of health promotions, targeting populations and ensuring their compliance, and establishing screening standards. The study also ensured that specialists administer the procedures using advanced technology, and further, controlled trials. The study also showed that the lessening of tobacco and alcohol use contribute to the slowdown of oral cancer cases. Moreover, early diagnoses reduce the likelihood of oral cancers and make it preventable (Chairman and Downer 1995).
In the same research review, the focus of prevention of oral cancer at the primary level is the prohibition of use of tobacco and alcohol, while recognizing white and red changes in the oral cavity as oral cancer precedents are aimed as a secondary prevention. There is good prognosis if oral cancer is cured at its early stage. Since the first clinical signals of oral cancer are red and white changes in the oral cavity, earlier diagnosis is strongly recommended. The authors also did not recommend exfoliative procedures because of likelihood for negative results.
However, for especially high-risk cases, a cold-knife surgery or laser surgery is preferred. If results reveal a presence of distinct epithelial dysplasia, treatment is strongly urged (Chairman and Downer 1995). Further, they also recommended a systematic dispensation of substances like beta-carotene and isoretinoin. Patients must continue with follow-up examinations and treatment because of the high risk of developing second and third primaries in respiratory and upper alimentary tracts.
Despite its traces being recognizable, as it can be found immediately in the oral cavity, signs have been neglected this making oral cancer a serious and fatal disease if not prevented. The appearance of red and white lesions or patches can already be a case of oral cancer. It can affect the patients quality of life because of the development of further complications if malignancies remain untreated. Treatment in these instances may already be costly. Prevention of the cancer at its pre-malignant phase should be prioritized. These are often detected during dental visits and oral examinations, thus, the role of the dentist is also crucial.
There is also greater need for public awareness. An information mechanism that would also target patients and those already with positive results is highly encouraged. Since the main risk factors include excessive alcohol and tobacco use (smoking and smokeless tobacco), health care professionals must recognize the importance of a healthy lifestyle, as well as a good diet, especially since nutrients can also help lessen oral cancer probability, e.g. beta-carotene.
Oral cancer is a serious disease considering there is a five-year survival rate among researches and studies undergone on the disease. Dentists and health care practitioners thus have a crucial role in ensuring that patients have regular and comprehensive examinations. Further, scientific research have shown the importance of molecular biology or epidemiology in advancing better treatment and curative measures of oral cancer, thus encouraging further engagements in research.
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