Dietary exposures and oral precancerous lesions in Srikakulam District, Andhra Pradesh, India

Global Scenario of Research in Oral Cancer

INTRODUCTION

With 300,000 new cases diagnosed worldwide, oral cancer continues to be a major global public threat. In Indian subcontinent, oral cancer accounts for 30-40% of all cancer types.

METHODOLOGY

Early detection of oral cancer is still considered as the most effective way to improve survival. In this regard, early detection of oral premalignant lesions and conditions is quite important as it may help in prevention of oral cancer. Scientific evidence is available which clearly indicates that transition from normal epithelium to premalignancy to oral carcinoma is the result of accumulation of genetic and epigenetic alterations in a multi-step process.

CONCLUSION

Proper oral screening and understanding of the genetic and environmental factors involved in oral carcinogenesis will allow the emphasis of cancer medicine to shift from the therapy of established oral cancer to the prevention of oral carcinogenesis.

Case-control study of candidate gene methylation and adenomatous polyp formation

PURPOSE

Colorectal cancer (CRC) is one of the most common and preventable forms of cancer but remains the second leading cause of cancer-related death. Colorectal adenomas are precursor lesions that develop in 70-90 % of CRC cases. Identification of peripheral biomarkers for adenomas would help to enhance screening efforts. This exploratory study examined the methylation status of 20 candidate markers in peripheral blood leukocytes and their association with adenoma formation.

METHODS

Patients recruited from a local endoscopy clinic provided informed consent and completed an interview to ascertain demographic, lifestyle, and adenoma risk factors. Cases were individuals with a histopathologically confirmed adenoma, and controls included patients with a normal colonoscopy or those with histopathological findings not requiring heightened surveillance (normal biopsy, hyperplastic polyp). Methylation-specific polymerase chain reaction was used to characterize candidate gene promoter methylation. Odds ratios (ORs) and 95 % confidence intervals (95% CIs) were calculated using unconditional multivariable logistic regression to test the hypothesis that candidate gene methylation differed between cases and controls, after adjustment for confounders.

RESULTS

Complete data were available for 107 participants; 36 % had adenomas (men 40 %, women 31 %). Hypomethylation of the MINT1 locus (OR 5.3, 95% CI 1.0-28.2) and the PER1 (OR 2.9, 95% CI 1.1-7.7) and PER3 (OR 11.6, 95% CI 1.6-78.5) clock gene promoters was more common among adenoma cases. While specificity was moderate to high for the three markers (71-97 %), sensitivity was relatively low (18-45 %).

CONCLUSION

Follow-up of these epigenetic markers is suggested to further evaluate their utility for adenoma screening or surveillance.

Development and evaluation of a Nutrition Transition-FFQ for adolescents in South India

OBJECTIVE

To develop and evaluate a Nutrition Transition-FFQ (NT-FFQ) to measure nutrition transition among adolescents in South India.

DESIGN

We developed an interviewer-administered NT-FFQ comprising a 125-item semi-quantitative FFQ and a twenty-seven-item eating behaviour survey. The reproducibility and validity of the NT-FFQ were assessed using Spearman correlations, intra-class correlation coefficients (ICC), and levels of agreement using Bland-Altman and cross-classification over 2 months (NT-FFQ1 and NT-FFQ2). Validity of foods was evaluated against three 24-h dietary recalls (24-HR). Face validity of eating behaviours was evaluated through semi-structured cognitive interviews. The reproducibility of eating behaviours was assessed using weighted kappa (κ w) and cross-classification analyses.

SETTING

Vijayapura, India.

SUBJECTS

A representative sample of 198 adolescents aged 14-18 years.

RESULTS

Reproducibility of NT-FFQ: Spearman correlations ranged from 0·33 (pulses) to 0·80 (red meat) and ICC from 0·05 (fruits) to 1·00 (tea). On average, concordance (agreement) was 60 % and discordance was 7 % for food groups. For eating behaviours, κ w ranged from 0·24 (eating snacks while watching television) to 0·67 (eating lunch at home) with a mean of 0·40. Validity of NT-FFQ: Spearman correlations ranged from 0·11 (fried traditional foods) to 0·70 (tea) and ICC ranged from 0·02 (healthy global foods) to 1·00 (grains). The concordance and discordance were 48 % and 8 %, respectively. Bland-Altman plots showed acceptable agreement between NT-FFQ2 and 24-HR. The eating behaviours had acceptable face validity.

CONCLUSIONS

The NT-FFQ has good reproducibility and acceptable validity for food intake and eating behaviours. The NT-FFQ can quantify the nutrition transition among Indian adolescents.

Dental Informatics tool "SOFPRO" for the study of oral submucous fibrosis

Background:

Dental informatics is an evolving branch widely used in dental education and practice. Numerous applications that support clinical care, education and research have been developed. However, very few such applications are developed and utilized in the epidemiological studies of oral submucous fibrosis (OSF) which is affecting a significant population of Asian countries.

Aims and Objectives:

To design and develop an user friendly software for the descriptive epidemiological study of OSF.

Materials and Methods:

With the help of a software engineer a computer program SOFPRO was designed and developed by using, Ms-Visual Basic 6.0 (VB), Ms-Access 2000, Crystal Report 7.0 and Ms-Paint in operating system XP. For the analysis purpose the available OSF data from the departmental precancer registry was fed into the SOFPRO.

Results:

Known data, not known and null data are successfully accepted in data entry and represented in data analysis of OSF. Smooth working of SOFPRO and its correct data flow was tested against real-time data of OSF.

Conclusion:

SOFPRO was found to be a user friendly automated tool for easy data collection, retrieval, management and analysis of OSF patients.

Prevalence of oral cancer and pre-cancerous lesions and the association with numerous risk factors in North India: A hospital based study

Background:

Oral cancer is one of the most common life-threatening diseases all over the world. Developing countries face several challenges to identify and remove potential risk factors. Chewing tobacco/pan masala is considered to be the most potent risk factor for oral precancerous lesions and oral cancer.

Objectives:

To investigate the relative occurrence of different oral pre-cancerous lesions and oral cancer in North India and to identify the associated risk factors.

Materials and Methods:

A hospital-based study was conducted and 471 subjects were recruited in the study. The subjects comprised patients with squamous cell carcinoma (n = 85), oral submucous fibrosis (n = 240), leukoplakia (n = 32), lichen planus (n = 15), and controls (n = 99). Statistical analysis of the data was done using Chi-square and regression analysis.

Results:

A strong correlation was observed between the presence of the chewing habit in all the oral precancerous lesions and oral cancer. Duration of the habit and intensity of habit ware also strongly correlated with the risk of oral precancerous lesions and oral cancer. Other factors such as alcohol and smoking were found to be less important in concern with oral cancer and precancerous lesions.

Tobacco control: an issue twinned with oral cancer control

Oral cancer is a silent crisis in India. Thirty per cent of all cancers are oral cancer, and approximately 17% of all cancers in men and 10.5% of all cancers in women are oral cancer. Approximately 70,000 new cases are reported annually and 46,000 oral cancer-related deaths occur each year in India; furthermore, the number of cases is rapidly increasing. With this crescendo there may be an estimated 100,000 new cases by 2020, which is insurmountable, especially in emerging economies like India. This astronomical increase is a direct result of tobacco usage. The Global Adult Tobacco Survey performed in 2010 (GATS-2010) reported that approximately 274.5 million people in India use tobacco in various forms. Increasing use of smokeless tobacco, especially by women and children, is of major concern. The World Health Organisation has identified tobacco control and oral cancer control measures as a health priority. However, prevention of tobacco use in India is a great challenge owing to low overall literacy rates and to greater prevalence among people in lower socio-economic strata. Addressing this problem requires a multidisciplinary approach. This paper presents a situational analysis of oral cancer in India and the role of tobacco in making it the epicentre of the disease, and focuses on the role of dental care-givers in influencing and promoting tobacco-control programmes and early detection of oral cancer.

Dash of faith: a faith-based participatory research pilot study

The Dash of Faith pilot used a community-based participatory research approach to design an experiential dietary intervention based on two African-American churches, one intervention and one comparison. Congregation members identified components that were incorporated into 12 weekly and 4 monthly sessions, with a goal of increasing fruit and vegetable and lowering fat intake. At 2 months, a marginally significant (p = 0.07) increase in fruit and vegetable consumption was observed in the intervention group but was not maintained at study conclusion. We propose that these mixed findings may be attributable, in part, to bias introduced by the participatory nature of the design.

Higher micronutrient intake is associated with human papillomavirus-positive head and neck cancer: a case-only analysis

No studies have investigated dietary differences between head and neck squamous cell carcinoma (HNSCC) patients with human papillomavirus (HPV)-positive tumors and patients with HPV-negative tumors. This study was designed to investigate the relationship between diet and HPV status in HNSCC patients. Cases of HNSCC were recruited from 2 clinical centers participating in the University of Michigan Head and Neck Specialized Program of Research Excellence (SPORE). HPV tissue genotyping was performed, and epidemiological and dietary data collected. Multivariable logistic regression tested whether pretreatment consumption of 12 selected micronutrients was significantly associated with HPV-positive status in 143 patients newly diagnosed with cancer of the oral cavity or pharynx. After controlling for age, sex, body mass index, tumor site, cancer stage, problem drinking, smoking, and energy intake, significant and positive associations were observed between vitamin A, vitamin E, iron, β-carotene, and folate intake and HPV-positive status (P(trend) < 0.05), suggesting that diet may be a factor in the improved prognosis documented in those with HPV-positive HNSCC. Dietary differences by HPV status should be considered in prognostic studies to better understand the influence of diet on HNSCC survival.

Relationship between Selected Socio-Demographic Factors and Cancer of Oral Cavity - A Case Control Study

The aim of this study was to recognize factors associated with cancer of oral cavity considering socio-demographic characteristics. The cases were 350 with squamous-cell carcinoma of oral cavity diagnosed between 2005 and 2006 in Morbai, Narandia, Budharani Cancer Institute, Pune, India. Similar number of controls match for age and sex selected from the background population. Cases and controls were interviewed for tobacco related habits and general characteristics; age, gender, education and possible socio-demographic factors. Chi-square test in uni-variate analysis and estimate for risk showed that education, occupation and monthly household income were significantly different between cases and controls (P < 0.001). Irrespective to gender, relative risk, here odds ratio, (OR) of low level of education (OR = 5.3, CI 3.7-7.6), working in field as a farmer (OR = 2.5, CI 1.7-3.7), and monthly household income less than 5000 Indian Rupees currency (OR = 1.7, CI 1.2-2.3) were significant risk factors for oral cancer. While, there was no significant relationship between religious and or marital status either in males or females.

A possible link between iron deficiency and gastrointestinal carcinogenesis

There is definitive evidence that iron overload induces oxidative stress and DNA damage, which can enhance carcinogenic risk. However, other evidence suggests that iron deficiency and anemia also increase oxidative stress and DNA damage, which might increase carcinogenesis risk, especially in the gastrointestinal (GI) tract. The aim of this review is to provide essential background information for the accurate interpretation of future research on iron deficiency and increased GI cancer risk. Based on clinical, epidemiological, and experimental evidence, we discuss how iron deficiency might contribute to increased cancer risk through the impairment of several iron-dependent metabolic functions that are related to genome protection and maintenance (e.g., immune responses against cancer-initiated cells, metabolism of toxic compounds, and redox regulation of DNA biosynthesis and repair). Some epidemiological studies have indicated increased risk of GI tumors among individuals with low iron intake or low somatic iron stores, and in vivo data from rodent cancer models indicates the early progression of GI tumors during iron deficiency. Given the preliminary but consistent evidence relating iron deficiency to cancer risk and the fact that iron deficiency affects about one third of the world's population, further studies are needed to define the extent to which iron deficiency might increase GI cancer risk.

Prospective study of vitamins C, E, and A and carotenoids and risk of oral premalignant lesions in men

Case-control studies indicate that vitamins C, E, A and carotenoids decrease risk of oral premalignant lesions (OPLs) and oral cancer, but clinical trials have failed to find protective effects of beta-carotene and suggest that vitamin E may increase risk. The authors prospectively evaluated the association between intake of vitamins C, E, A and carotenoids and incidence of OPL. Participants were 42,340 men in the Health Professionals Follow-up Study who provided information on supplement use and diet every 2-4 years by food frequency questionnaire. The authors confirmed 207 clinically or histopathologically diagnosed OPL events occurring between 1986 and 2002 by medical record review. Multivariate-adjusted relative risks (RR) of OPL were calculated with proportional hazards models. Total intake of vitamin C, vitamin A or carotenoids was not significantly associated with OPL risk. Dietary vitamin C was significantly associated with reduced risk (quintile 5 vs. 1, RR = 0.52, 95% CI 0.31-0.85, p(trend) = 0.04), but no association with supplemental vitamin C was observed. Inverse associations were apparent for beta-cryptoxanthin and alpha-carotene intake. No clear relationship emerged with beta-carotene, lycopene or lutein/zeaxanthin. Vitamin E was associated with increased risk (quintile 5 vs. 1, RR = 1.86, 95% CI 1.06-3.19), particularly among current smokers and with supplemental intake (current-smokers, supplement dose tertile 3 vs. 1, RR = 3.07, 95% CI 1.28-7.34, p(trend) = 0.01). For current smokers, beta-carotene also increased risk. Vitamin C from dietary sources, but not supplements, was associated with a reduced risk of OPL. The observed increased risk for current smokers with high vitamin E or beta-carotene intake should be explored further.

Prospective study of fruits and vegetables and risk of oral premalignant lesions in men

The authors prospectively evaluated fruit and vegetable consumption and the incidence of oral premalignant lesions among 42,311 US men in the Health Professionals Follow-up Study. Diet was assessed every 4 years by food frequency questionnaires. The authors confirmed 207 cases of clinically or histopathologically diagnosed oral premalignant lesions occurring between 1986 and 2002. Multivariate-adjusted relative risks were calculated from proportional hazards models. Significant inverse associations were observed with citrus fruits, citrus fruit juice, and vitamin-C-rich fruits and vegetables, indicating 30-40% lower risks with greater intakes (e.g., citrus fruit juice quintile 5 vs. quintile 1 relative risk = 0.65, 95% confidence interval: 0.42, 0.99). Inverse associations with fruits did not vary by smoking status and were stronger in analyses of baseline consumption, with a 10-year lag time to disease follow-up (quintile 5 vs. quintile 1 relative risk = 0.41, 95% confidence interval: 0.20, 0.82; p = 0.01). No associations were observed with total vegetables or with beta-carotene-rich or lycopene-rich fruits and vegetables. For current smokers, green leafy vegetables (ptrend = 0.05) and beta-carotene-rich fruits and vegetables (ptrend = 0.02) showed significant linear trends of increased risk (one additional serving/day relative risk = 1.7). The risk of oral premalignant lesions was significantly reduced with higher consumption of fruits, particularly citrus fruits and juices, while no consistent associations were apparent for vegetables.

Association between tobacco use and body mass index in urban Indian population: implications for public health in India

BACKGROUND

Body mass index [BMI, weight (kg)/height (m2)], a measure of relative weight, is a good overall indicator of nutritional status and predictor of overall health. As in many developing countries, the high prevalence of very low BMIs in India represents an important public health risk. Tobacco, smoked in the form of cigarettes or bidis (handmade by rolling a dried rectangular piece of temburni leaf with 0.15-0.25 g of tobacco) or chewed, is another important determinant of health. Tobacco use also may exert a strong influence on BMI.

METHODS

The relationship between very low BMI (< 18.5 kg/m2) and tobacco use was examined using data from a representative cross-sectional survey of 99,598 adults (40,071 men and 59,527 women) carried out in the city of Mumbai (formerly known as Bombay) in western India. Participants were men and women aged > or = 35 years who were residents of the main city of Mumbai.

RESULTS

All forms of tobacco use were associated with low BMI. The prevalence of low BMI was highest in bidi-smokers (32% compared to 13% in non-users). For smokers, the adjusted odds ratio (OR) and 95% confidence interval (CI) were OR = 1.80(1.65 to 1.96) for men and OR = 1.59(1.09 to 2.32) for women, respectively, relative to non-users. For smokeless tobacco and mixed habits (smoking and smokeless tobacco), OR = 1.28(1.19 to 1.38) and OR = 1.83(1.67 to 2.00) for men and OR = 1.50(1.43 to 1.59) and OR = 2.19(1.90 to 3.41) for women, respectively.

CONCLUSION

Tobacco use appears to be an independent risk factor for low BMI in this population. We conclude that in such populations tobacco control research and interventions will need to be conducted in concert with nutrition research and interventions in order to improve the overall health status of the population.