|Year : 2016 | Volume
| Issue : 2 | Page : 244-251
Squamous cell carcinoma of the oral cavity and oropharynx in patients aged 18–45 years: A case–control study to evaluate the risk factors with emphasis on stress, diet, oral hygiene, and family history
KP Dholam, GC Chouksey
Department of Dental and Prosthetic Oncology, Tata Memorial Hospital, Mumbai, Maharashtra, India
|Date of Web Publication||6-Jan-2017|
G C Chouksey
Department of Dental and Prosthetic Oncology, Tata Memorial Hospital, Mumbai, Maharashtra
Source of Support: None, Conflict of Interest: None
Background: Increasing incidence of squamous cell carcinoma (SCC) of the oral cavity and oropharynx is reported in young adults. However, there is a paucity regarding etiology and risk factors. Aim: To evaluate the exposure potential carcinogenic factors among a sample aged 45 years and younger, diagnosed with SCC of the oral cavity and oropharynx. Methodology: Eighty-five case samples aged 18–45 years, diagnosed with SCC of the oral cavity and oropharynx were compared with 85 controls who had never had cancer, matched for age and sex. This study was conducted by questionnaire-based interviews. Questionnaire contained items about exposure to the following risk factors: Caries prevalence, oral hygiene status, dental trauma, dental visit, stress, family history of cancer, environmental exposure to potential carcinogens, diet, body mass index (BMI), habits such as smoking, tobacco chewing, betel quid/pan, or supari. Statistical Analysis: Odds ratios (ORs) of oral and pharyngeal cancer and the corresponding 95% confidence intervals were estimated using multiple logistic regression models. P< 0.05 was considered statistically significant. Results: Elevated OR was seen in young adults who had poor oral hygiene, stress, dental trauma, low BMI, family history of cancer, exposure to environmental carcinogens, and habit of placement of quid for 11–20 years. Conclusions: An increased risk of oral and pharyngeal cancer was seen in cases who had poor oral hygiene, stress, dental trauma, low BMI, family history of cancer, exposure to environmental carcinogens, and habit of placement of quid.
Keywords: Caries prevalence, dental trauma, diet, family history, oral hygiene, squamous cell carcinoma, stress, young adult
|How to cite this article:|
Dholam K P, Chouksey G C. Squamous cell carcinoma of the oral cavity and oropharynx in patients aged 18–45 years: A case–control study to evaluate the risk factors with emphasis on stress, diet, oral hygiene, and family history. Indian J Cancer 2016;53:244-51
|How to cite this URL:|
Dholam K P, Chouksey G C. Squamous cell carcinoma of the oral cavity and oropharynx in patients aged 18–45 years: A case–control study to evaluate the risk factors with emphasis on stress, diet, oral hygiene, and family history. Indian J Cancer [serial online] 2016 [cited 2020 Apr 7];53:244-51. Available from: http://www.indianjcancer.com/text.asp?2016/53/2/244/197725
| » Introduction|| |
Squamous cell carcinoma (SCC) in the oral cavity and oropharynx is uncommon before the age of 35 years., There is a paucity of information regarding its etiology, natural history, and optimal therapeutic management. However, even when young patients have indulged in the risk factors of tobacco and alcohol, it is for considerably shorter periods compared with the older age group.
It is essential to examine the potential risk factors such as environmental carcinogens, stress, previous viral infections, and familial episodes of cancer  and likely protective factors such as diet (consumption of fruits and vegetables) to provide a better insight to etiology of SCC. Emerging evidence also shows role of human papillomavirus infection in some subsites. Occupational exposures are a known risk factor for upper aerodigestive tract tumors.,,,, Low socioeconomic status and a downward trajectory of social position over the life course are also confounding factors , that increase the risk.,
To evaluate the exposure potential carcinogenic factors among a sample aged 45 years and younger, diagnosed with SCC of the oral cavity and oropharynx.
- To assess caries prevalence and oral hygiene status in this group of patients
- To find association of stress, environmental carcinogens, trauma, diet, family history, habits (duration and frequency), region of placement of quid, body mass index (BMI), and dental visits with occurrence of cancer
- To find association of area where the tobacco quid was placed in the mouth with occurrence of cancer.
| » Methodology|| |
Recruitment of cases and control
Patients aged between 18 and 45 years, newly diagnosed with SCC of oral cavity and oropharynx were included in the study. Subjects with cancers of the oral cavity (lip, buccal mucosa, lower alveolus, retromolar trigone, oral tongue, floor of mouth, upper alveolus, and hard palate) and oropharynx were observed. Patients with cancers of the salivary glands, nasopharynx, and hypopharynx were not included.
Control subjects were patients aged 18–45 years, with no history of trauma, precancerous lesions, cancerous lesions, or any other pathology in head and neck region. They were selected from the general population in the outpatient department. Controls were matched by age (±5 years) and sex with the study case subjects. Control to case ratio was 1:1.
This study was conducted by questionnaire-based interviews which were conducted by a single investigator for the study subjects and the controls. The questionnaire contained questions pertaining to demographic details such as age, gender, education, occupation, and BMI. Information related to age at diagnosis of tumor, tumor site, tumor stage, and treatment details was obtained. Details of consumption of the amount of fresh fruits and vegetables consumed regularly, stress, dental trauma, environmental exposure to potential carcinogens, dental/oral health, and general health questions were noted. Familial episodes of cancer were also recorded. Caries prevalence and oral hygiene were assessed with decayed, missing, filled teeth (DMFT) index and oral hygiene index simplified (OHIS), respectively. Age at the initiation of tobacco habits and alcohol use before cancer diagnosis was recorded. Details of smoking and tobacco chewing included type, number per day, and duration of the habit. To account for the social habits among Asian ethnic minorities, additional questions on consumption of betel quid/pan or supari were included. This study was approved by the Institutional Review Board and was registered with the Clinical Trials Registry-India (CTRI/2014/07/004762).
Demographic variables were presented as mean (standard deviation), median, or frequencies (percentages). Categorical variables were analyzed using Chi-square test or Fisher's exact test (for binary data). Odds ratios (ORs) of oral and pharyngeal cancer and the corresponding 95% confidence intervals (CI) were estimated using multiple logistic regression models. P < 0.05 was considered statistically significant. Analysis was conducted using IBM SPSS version 20.
| » Results|| |
Association of caries prevalence, oral hygiene, stress, environmental carcinogens, trauma, diet, family history, habits (duration and frequency), region of placement of quid, BMI, and dental visits with occurrence of cancer in this case and control study was as follows.
Eighty-nine percent of the sample was male with more than 60% of case and control samples in the age group of 31–40 years. Only 18% of the case and 31% of the control sample belonged to high educational qualification. Approximately 50% of the population was in the laborer group and <12% of the subjects were unemployed.
Mixed diet was prevalent in more than 70% of patients and 90% used right hand to eat the food.
Sixty-five percent of the patients had histologically proven moderately differentiated SCC. Thirty-nine percent of the patients had Stage IV cancer at the time of diagnosis. Sixty percent of the patients were in the age group of 31–40 years. Most common cancer seen was involving buccal mucosa (39%) followed by the tongue (31%). Cancer involving tonsil/oropharynx was seen in 6% of the case subjects. Fifteen percent of the patients were treated by surgery alone while 78% received radiation therapy along with surgery.
DMFT score between 1 and 10 was seen in more than 80% of cases and controls, but the result was not statistically significant [Table 1].
|Table 1: Caries prevalence, oral hygiene status, dental trauma, dental visit|
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Moderate and poor oral hygiene was seen in 45% and 34% of the case samples, respectively. On the contrary, 64% of the control samples had good oral hygiene. Hence, an increased risk is seen in samples who have OHIS scoring 3–4 (OR: 4.385, 95% CI: 2.112–9.101) and 5–6 (OR: 17.4000, 95% CI: 5.858–51.686) [Table 1].
Dental trauma was seen in 33% of case samples as compared with 4% of control samples (P = 0.000); hence, an increased risk of oral cancer was seen in samples who have dental trauma (OR: 13.427, 95% CI: 3.894–46.292) [Table 1].
No significant difference was seen in dental visit among the cases and control samples as majority visited less than once a year [Table 1].
Forty-eight (48%) percent of the case samples felt that stress was associated with their current health problem (P = 0.000), with an increased risk seen in samples who have stress associated with their current health problem (OR: 5.669, 95% CI: 2.693–11.930) [Table 2].
Twenty-six percent of case samples had family history of cancer compared with 48% of control subjects (P = 0.003). In subjects with a positive family history, association with cancer was statistically significant (OR: 0.375, 95% CI: 0.197–0.715) [Table 3].
Eighty-eight percent of case samples and 45% of control subjects had lifestyle that increased the risk of cancer (P = 0.000, OR: 9.276, 95% CI: 4.226–20.363). The findings with other causes namely naturally occurring exposures, medical treatments, workplace, household exposure, and pollution were not statistically significant [Table 3].
Surprisingly, more than 94% of the samples (cases and controls) had zero serving of fresh fruits in a day. Green leafy vegetables were mostly consumed once or twice a week by both case and control samples. More than 60% of the subjects consumed one serving per day of other vegetables including roots and tubers. All results were not statistically significant [Table 4].
Eighty-six percent of case and 65% of control samples had BMI <25. Among control subjects, overweight and obese category was seen in 29% and 6%, respectively. An increase in risk of oral and pharyngeal cancer was associated with underweight as compared to overweight (P = 0.012, OR: 0.244, 95% CI: 0.066–0.034) [Table 4].
Habit of chewing tobacco was seen in 74% of case samples and 31% of control samples. Smoking was noted in 31% and 18% of case and control samples, respectively. Twenty percent and 6% of case and control samples consumed alcohol. Betel nut/pan/supari chewing was seen in 35% of case and 22% of control samples. Indulgence in habits was seen after attaining 16 years of age [Table 5].
The habit of placing quid in the mouth was seen in 61 (72%) case subjects and 26 (31%) control subjects. Fifty-nine percent (36/61) of the case samples placed the quid in the mouth for almost 11–20 years (P = 0.006). An increase in risk of oral and pharyngeal cancer was associated with placement of quid in mouth for 11–20 years (OR: 5.368, 95% CI: 1.816–15.872) [Table 6].
More than 57% (35/61) of the case subjects and 38% (10/26) of the control samples had the habit of placing quid in the left buccal fold. Lesion was noticed in the same area where the tobacco quid was placed in the mouth in 59% (36/61) of the case subjects [Table 6].
| » Discussion|| |
The primary aim of this case–control study was to evaluate the major risk factors for SCC of the oral cavity and oropharynx in patients aged 18–45 years with emphasis on stress, diet, oral hygiene, and family history. In total, 85 cases and 85 controls were recruited for the study. This is the one of the largest case–control study so far to be undertaken on young subjects diagnosed with cancer of oral cavity and oropharynx in India.
Oral SCC is more common in men than in women;,,, however, there have been conflicting reports. In the present study, 76 (89%) of the cases were found to be men and only 9 (11%) women, a ratio of 8.4:1. These findings are in accordance to the studies of Llewellyn et al., Iamaroon et al., and Ribeiro et al. that reported higher incidences in men under 45 years old. However, Kuriakose et al. reported that cancer prevailed more in women in a proportion of 1.2:1 in a group of patients less than 35 years old.
Guha et al. stated that poor general oral condition was associated with an increased risk of oral cavity and oropharyngeal cancers. It has been previously observed that periodontitis is associated with increased risk of head and neck SCC (HNSCC)., In the present study, analysis of oral hygiene by OHIS showed that more case subjects had moderate and poor oral hygiene, i.e. 45% and 34%, respectively. On the contrary, 64% of the controls samples had good oral hygiene. Hence, an increased risk was seen in samples who have OHIS scoring 3–4 and 5–6 [Table 1].
The results of this study showed that more than 80% of cases and controls had 1–10 teeth affected by caries, but the result was not statistically significant [Table 1]. Tezal et al. found that dental caries was associated with HNSCC. The DMFT index is an indicator of the overall dental status in the oral cavity, but the decayed tooth or a badly filled tooth can cause chronic trauma and infection, leading to oral cancer.
Dental factors namely trauma due to sharp teeth, less than ideal fillings, badly fitting dentures or unsuitable denture-bearing tissue, and loose anchoring attachments contribute to the etiology of oral SCC.,, Dental trauma as a risk factor was statistically significant (P = 0.000) with an increased risk seen in samples who have dental trauma [Table 1]. A review relating cancer to trauma by Monkman et al. found no evidence to suggest that single uncomplicated trauma can cause cancer. However, they concluded that trauma in combination with other factors may act as a co-carcinogen. There was adequate evidence suggesting that metastatic spread of malignant tumors can be affected by trauma. Early recognition of the lesions in oral soft tissues caused due to dental irritation as well as multidisciplinary management may help in the prognosis of these cases.
Early detection of precancerous lesion was absent in all the study patients due to lack of timely oral screening. No significant difference was seen in dental visit among both the groups [Table 1].
An increased risk of oral and pharyngeal cancer was seen in samples who have stress associated with their current health problem [Table 2]. In a study by Llewellyn et al., it was found that the risk of delay in presentation among younger patients with oral cancer was also 7-fold higher for patients reporting stress in the period prior to diagnosis. This may be because of other commitments at work or home preventing the patient from attending to symptoms more carefully or indeed making the time to visit a health care professional. Stress is unfortunately a symptom of modern life but may be responsible for longer delays in diagnosis.
Current evidence suggests that damage to genetic blueprint of cells (DNA) can cause cancer. Some of these changes may be inherited from our parents while others may be caused by environmental factors.
Onset of cancer at an early age is thought to be an indicator of hereditary cancer. Studies have shown higher familial risks in first-degree relatives where the cancer was diagnosed at a young age., Increased risk more than 2-fold in siblings is seen if the onset occurred before age 50. However, in this study, we found that more control samples (48%) had family history of cancer than case samples (26%) [Table 3]. A possible reason to explain this is that control subjects were mostly people who accompanied cases and were their relatives.
Environmental factors can include a wide range of exposures, such as lifestyle factors (nutrition, tobacco use, physical activity, etc.), naturally occurring exposures (ultraviolet light, radon gas, infectious agents, etc.), medical treatments (radiation and medicines including chemotherapy, hormone drugs, drugs that suppress the immune system, etc.), workplace exposures, household exposures, and pollution. In this study, risk of lifestyle factors was found to be statistically significant. However, only 40% of both case and control samples were exposed to naturally occurring environmental carcinogens and workplace exposures. Fifty-eight percent of both the groups were exposed to pollution [Table 3]. None of them had any previous medical treatments that could be termed under environmental carcinogens. Household exposures were seen in 27% and 32% of the case and control samples, respectively. However, all the other factors (naturally occurring exposures, medical treatments, workplace, household exposure, and pollution) were not found to be significant.
The protective role of vegetables and fruits on oral cavity and pharyngeal (OCP) cancer has been attributed to several micronutrients, including carotenoids and Vitamins C and E, found to be inversely related to OCP cancer.,,,, These components display both complementary and overlapping mechanisms of action, including antioxidant effects and binding and dilution of carcinogens in the digestive tract., In this study, diet as a risk factor for OCP cancer was not statistically significant [Table 4]. The results are similar to another study on young adults where no significant difference was seen between males and females in the amount of fresh fruits and vegetables consumed in childhood and the 10 years before diagnosis. However, case–control studies have consistently shown that oral cancer patients of all ages tend to have histories of diets low in fruit and vegetables.,,,,,, Not many studies have quantified diet as a risk factor in young cancer cases.
Eighty-six percent of case and 65% of control samples had BMI <25 [Table 4]. In the overweight and obese category, more number of control subjects here as compared to case subjects. The findings of this study confirm that patients with cancers of the oral cavity and oropharynx tend to have a lower BMI, although this could be partly a consequence of the habits and the disease leading to poor nutritional status, rather than a cause, of the oral lesions. This is in accordance to the study by Rodriguez et al. and Franceschi  and Radoï et al.
Among the various habits [Table 5] namely chewing tobacco, smoking, alcohol consumption, betel nut/pan/supari chewing, and placement of quid in the mouth, significant risk was seen in patients who had the habit of placing quid in the mouth for 11–20 years (P = 0.006). This finding is not consistent with previous studies of young patients, whereby none of the usual risk factors of smoking, chewing tobacco, and excessive drinking contributed to the disease.,,,
There is a strong correlation between hand used to eat the food, area where the tobacco quid was placed in the mouth, and where the lesion was first noticed in the mouth [Table 6].
This is not a retrospective study; hence, there was no recall bias. The subjects did not have problems understanding the questions as the interview was conducted by a single clinician. Cases who were diagnosed and were undergoing cancer treatment at the institution were enrolled. The limitation of this study is that control samples were selected from general population at the outpatient department who were mostly relatives of the patient. A more detailed screening with respect to nutrition and viral infections with emphasis on would give us further insight into the assessment of additional factors contributing to oral cancers.
| » Conclusion|| |
Poor oral hygiene, chronic dental trauma and infection associated with carious and periodontally affected teeth, increases the risk of oral and pharyngeal carcinoma. Stress of commitment from work or family results in negligence and delays the patient from attending the ongoing symptoms. Among the environmental factors, lifestyle factors mainly nutrition, tobacco use, and physical activity too increase the risk of oral cancer. Role of genetic and hereditary factors too was found to play a role in the occurrence of SCC of oral cavity and oropharynx. Among the various habits, placement of quid in mouth contributed to occurrence of oral cancer. A strong correlation was seen among patients who used right hand to eat the food with occurrence of lesion on the left side of oral cavity. The presence of habits affects physical health and causes low BMI in cancer patients. Dietary factors with particular emphasis on fruits and vegetables and frequency of dental visit were not found to be significant.
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Conflicts of interest
There are no conflicts of interest.
| » References|| |
Hart AK, Karakla DW, Pitman KT, Adams JF. Oral and oropharyngeal squamous cell carcinoma in young adults: A report on 13 cases and review of the literature. Otolaryngol Head Neck Surg 1999;120:828-33.
Llewellyn CD, Linklater K, Bell J, Johnson NW, Warnakulasuriya KA. Squamous cell carcinoma of the oral cavity in patients aged 45 years and under: A descriptive analysis of 116 cases diagnosed in the South East of England from 1990 to 1997. Oral Oncol 2003;39:106-14.
Iype EM, Pandey M, Mathew A, Thomas G, Sebastian P, Nair MK. Oral cancer among patients under the age of 35 years. J Postgrad Med 2001;47:171-6.
Oliver RJ, Dearing J, Hindle I. Oral cancer in young adults: Report of three cases and review of the literature. Br Dent J 2000;188:362-5.
Llewellyn CD, Linklater K, Bell J, Johnson NW, Warnakulasuriya S. An analysis of risk factors for oral cancer in young people: A case-control study. Oral Oncol 2004;40:304-13.
D'Souza G, Kreimer AR, Viscidi R, Pawlita M, Fakhry C, Koch WM, et al.
Case-control study of human papillomavirus and oropharyngeal cancer. N Engl J Med 2007;356:1944-56.
Purdue MP, Järvholm B, Bergdahl IA, Hayes RB, Baris D. Occupational exposures and head and neck cancers among Swedish construction workers. Scand J Work Environ Health 2006;32:270-5.
Tarvainen L, Kyyrönen P, Kauppinen T, Pukkala E. Cancer of the mouth and pharynx, occupation and exposure to chemical agents in Finland [in 1971-95]. Int J Cancer 2008;123:653-9.
Dietz A, Ramroth H, Urban T, Ahrens W, Becher H. Exposure to cement dust, related occupational groups and laryngeal cancer risk: Results of a population based case-control study. Int J Cancer 2004;108:907-11.
Ramroth H, Dietz A, Ahrens W, Becher H. Occupational wood dust exposure and the risk of laryngeal cancer: A population based case-control study in Germany. Am J Ind Med 2008;51:648-55.
Richiardi L, Corbin M, Marron M, Ahrens W, Pohlabeln H, Lagiou P, et al.
Occupation and risk of upper aerodigestive tract cancer: The ARCAGE study. Int J Cancer 2012;130:2397-406.
Conway DI, Petticrew M, Marlborough H, Berthiller J, Hashibe M, Macpherson LM. Socioeconomic inequalities and oral cancer risk: A systematic review and meta-analysis of case-control studies. Int J Cancer 2008;122:2811-9.
Schmeisser N, Conway DI, McKinney PA, McMahon AD, Pohlabeln H, Marron M, et al.
Life course social mobility and risk of upper aerodigestive tract cancer in men. Eur J Epidemiol 2010;25:173-82.
Sasaki T, Moles DR, Imai Y, Speight PM. Clinico-pathological features of squamous cell carcinoma of the oral cavity in patients <40 years of age. J Oral Pathol Med 2005;34:129-33.
Bsoul SA, Huber MA, Terezhalmy GT. Squamous cell carcinoma of the oral tissues: A comprehensive review for oral healthcare providers. J Contemp Dent Pract 2005;6:1-16.
Scully C, Felix DH. Oral medicine – Update for the dental practitioner orofacial pain. Br Dent J 2006;200:75-83.
Massano J, Regateiro FS, Januário G, Ferreira A. Oral squamous cell carcinoma: Review of prognostic and predictive factors. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;102:67-76.
Llewellyn CD, Johnson NW, Warnakulasuriya KA. Risk factors for oral cancer in newly diagnosed patients aged 45 years and younger: A case-control study in Southern England. J Oral Pathol Med 2004;33:525-32.
Iamaroon A, Pattanaporn K, Pongsiriwet S, Wanachantararak S, Prapayasatok S, Jittidecharaks S, et al.
Analysis of 587 cases of oral squamous cell carcinoma in northern Thailand with a focus on young people. Int J Oral Maxillofac Surg 2004;33:84-8.
Ribeiro AC, Silva AR, Simonato LE, Salzedas LM, Sundefeld ML, Soubhia AM. Clinical and histopathological analysis of oral squamous cell carcinoma in young people: A descriptive study in Brazilians. Br J Oral Maxillofac Surg 2009;47:95-8.
Kuriakose M, Sankaranarayanan M, Nair MK, Cherian T, Sugar AW, Scully C, et al.
Comparison of oral squamous cell carcinoma in younger and older patients in India. Eur J Cancer B Oral Oncol 1992;28B: 113-20.
Guha N, Boffetta P, Wünsch Filho V, Eluf Neto J, Shangina O, Zaridze D, et al.
Oral health and risk of squamous cell carcinoma of the head and neck and esophagus: Results of two multicentric case-control studies. Am J Epidemiol 2007;166:1159-73.
Tezal M, Grossi SG, Genco RJ. Is periodontitis associated with oral neoplasms? J Periodontol 2005;76:406-10.
Tezal M, Sullivan MA, Hyland A, Marshall JR, Stoler D, Reid ME, et al.
Chronic periodontitis and the incidence of head and neck squamous cell carcinoma. Cancer Epidemiol Biomarkers Prev 2009;18:2406-12.
Tezal M, Scannapieco FA, Wactawski-Wende J, Meurman JH, Marshall JR, Rojas IG, et al.
Dental caries and head and neck cancers. JAMA Otolaryngol Head Neck Surg 2013;139:1054-60.
Orbak R, Bayraktar C, Kavrut F, Gundogdu C. Poor oral hygiene and dental trauma as the precipitating factors of squamous cell carcinoma. Oral Oncol 2005;41:109-13.
Thumfart W, Weidenbecher M, Waller G, Pesch HG. Chronic mechanical trauma in the aetiology of oro-pharyngeal carcinoma. J Maxillofac Surg 1978;6:217-21.
Randhawa T, Shameena P, Sudha S, Nair R. Squamous cell carcinoma of tongue in a 19-year-old female. Indian J Cancer 2008;45:128-30.
Monkman GR, Orwoll G, Ivins JC. Trauma and oncogenesis. Mayo Clin Proc 1974;49:157-63.
Llewellyn CD, Johnson NW, Warnakulasuriya S. Factors associated with delay in presentation among younger patients with oral cancer. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2004;97:707-13.
Stephen FO, Aigner KR. Basics of Oncology. Berlin, Heidelberg: Springer-Verlag; 2009. p. 9.
Lynch HT, Fusaro RM, Lynch J. Hereditary cancer in adults. Cancer Detect Prev 1995;19:219-33.
Goldgar DE, Easton DF, Cannon-Albright LA, Skolnick MH. Systematic population-based assessment of cancer risk in first-degree relatives of cancer probands. J Natl Cancer Inst 1994;86:1600-8.
Harvard Report on Cancer Prevention. Volume 1: Causes of human cancer. Cancer Causes Control 1996;7 Suppl 1:S3-59.
Copper MP, Jovanovic A, Nauta JJ, Braakhuis BJ, de Vries N, van der Waal I, et al.
Role of genetic factors in the etiology of squamous cell carcinoma of the head and neck. Arch Otolaryngol Head Neck Surg 1995;121:157-60.
Bravi F, Bosetti C, Filomeno M, Levi F, Garavello W, Galimberti S, et al.
Foods, nutrients and the risk of oral and pharyngeal cancer. Br J Cancer 2013;109:2904-10.
World Cancer Research Fund and American Institute for Cancer Research. Food, Nutrition, Physical Activity and the Prevention of Cancer: A Global Perspective. Washington, DC: American Institute for Cancer Research; 2007.
Bradshaw PT, Siega-Riz AM, Campbell M, Weissler MC, Funkhouser WK, Olshan AF. Associations between dietary patterns and head and neck cancer: The Carolina head and neck cancer epidemiology study. Am J Epidemiol 2012;175:1225-33.
Lucenteforte E, Garavello W, Bosetti C, La Vecchia C. Dietary factors and oral and pharyngeal cancer risk. Oral Oncol 2009;45:461-7.
Negri E, Franceschi S, Bosetti C, Levi F, Conti E, Parpinel M, et al.
Selected micronutrients and oral and pharyngeal cancer. Int J Cancer 2000;86:122-7.
Potter JD, Steinmetz K. Vegetables, fruit and phytoestrogens as preventive agents. IARC Sci Publ 1996;139:61-90.
IARC. IARC Handbooks of Cancer Prevention. Fruit and Vegetables. Vol. 8. Lyon: IARC; 2003.
Franceschi S, Bidoli E, Barón AE, Barra S, Talamini R, Serraino D, et al.
Nutrition and cancer of the oral cavity and pharynx in north-east Italy. Int J Cancer 1991;47:20-5.
Scully C. Oral precancer: Preventive and medical approaches to management. Eur J Cancer B Oral Oncol 1995;31B: 16-26.
Franco EL, Kowalski LP, Oliveira BV, Curado MP, Pereira RN, Silva ME, et al.
Risk factors for oral cancer in Brazil: A case-control study. Int J Cancer 1989;43:992-1000.
La Vecchia C, Negri E, D'Avanzo B, Boyle P, Franceschi S. Dietary indicators of oral and pharyngeal cancer. Int J Epidemiol 1991;20:39-44.
Levi F, Pasche C, La Vecchia C, Lucchini F, Franceschi S, Monnier P. Food groups and risk of oral and pharyngeal cancer. Int J Cancer 1998;77:705-9.
McLaughlin JK, Gridley G, Block G, Winn DM, Preston-Martin S, Schoenberg JB, et al.
Dietary factors in oral and pharyngeal cancer. J Natl Cancer Inst 1988;80:1237-43.
Winn DM, Ziegler RG, Pickle LW, Gridley G, Blot WJ, Hoover RN. Diet in the etiology of oral and pharyngeal cancer among women from the southern United States. Cancer Res 1984;44:1216-22.
Rodriguez T, Altieri A, Chatenoud L, Gallus S, Bosetti C, Negri E, et al.
Risk factors for oral and pharyngeal cancer in young adults. Oral Oncol 2004;40:207-13.
Franceschi S, Dal Maso L, Levi F, Conti E, Talamini R, La Vecchia C. Leanness as early marker of cancer of the oral cavity and pharynx. Ann Oncol 2001;12:331-6.
Radoï L, Paget-Bailly S, Cyr D, Papadopoulos A, Guida F, Tarnaud C, et al.
Body mass index, body mass change, and risk of oral cavity cancer: Results of a large population-based case-control study, the ICARE study. Cancer Causes Control 2013;24:1437-48.
Newman AN, Rice DH, Ossoff RH, Sisson GA. Carcinoma of the tongue in persons younger than 30 years of age. Arch Otolaryngol 1983;109:302-4.
Sankaranarayanan R, Mohideen MN, Nair MK, Padmanabhan TK. Aetiology of oral cancer in patients less than or equal to 30 years of age. Br J Cancer 1989;59:439-40.
Byers RM. Squamous cell carcinoma of the oral tongue in patients less than thirty years of age. Am J Surg 1975;130:475-8.
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]
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